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1.
Small ; : e2402649, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38949403

RESUMO

The utilization of the organic-inorganic hybrid photocatalysts for water splitting has gained significant attention due to their ability to combine the advantages of both materials and generate synergistic effects. However, they are still far from practical application due to the limited understanding of the interactions between these two components and the complexity of their preparation process. Herein, a facial approach by combining a glycolated conjugated polymer with a TiO2-X mesoporous sphere to prepare high-efficiency hybrid photocatalysts is presented. The functionalization of conjugated polymers with hydrophilic oligo (ethylene glycol) side chains can not only facilitate the dispersion of conjugated polymers in water but also promote the interaction with TiO2-X forming stable heterojunction nanoparticles. An apparent quantum yield of 53.3% at 365 nm and a hydrogen evolution rate of 35.7 mmol h-1 g-1 is achieved by the photocatalyst in the presence of Pt co-catalyst. Advanced photophysical studies based on femtosecond transient absorption spectroscopy and in situ, XPS analyses reveal the charge transfer mechanism at type II heterojunction interfaces. This work shows the promising prospect of glycolated polymers in the construction of hybrid heterojunctions for photocatalytic hydrogen production and offers a deep understanding of high photocatalytic performance by such heterojunction photocatalysts.

2.
Cardiovasc Diabetol ; 23(1): 193, 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38844938

RESUMO

BACKGROUND: The triglyceride-glucose (TyG) index, a tool for assessing insulin resistance, is increasingly recognized for its ability to predict cardiovascular and metabolic risks. However, its relationship with trauma and surgical patient prognosis is understudied. This study investigated the correlation between the TyG index and mortality risk in surgical/trauma ICU patients to identify high-risk individuals and improve prognostic strategies. METHODS: This study identified patients requiring trauma/surgical ICU admission from the Medical Information Mart for Intensive Care (MIMIC-IV) database, and divided them into tertiles based on the TyG index. The outcomes included 28-day mortality and 180-day mortality for short-term and long-term prognosis. The associations between the TyG index and clinical outcomes in patients were elucidated using Cox proportional hazards regression analysis and RCS models. RESULTS: A total of 2103 patients were enrolled. The 28-day mortality and 180-day mortality rates reached 18% and 24%, respectively. Multivariate Cox proportional hazards analysis revealed that an elevated TyG index was significantly related to 28-day and 180-day mortality after covariates adjusting. An elevated TyG index was significantly associated with 28-day mortality (adjusted hazard ratio, 1.19; 95% confidence interval 1.04-1.37) and 180-day mortality (adjusted hazard ratio, 1.24; 95% confidence interval 1.11-1.39). RCS models revealed that a progressively increasing risk of mortality was related to an elevated TyG index. According to our subgroup analysis, an elevated TyG index is associated with increased risk of 28-day and 180-day mortality in critically ill patients younger than 60 years old, as well as those with concomitant stroke or cardiovascular diseases. Additionally, in nondiabetic patients, an elevated TyG index is associated with 180-day mortality. CONCLUSION: An increasing risk of mortality was related to an elevated TyG index. In critically ill patients younger than 60 years old, as well as those with concomitant stroke or cardiovascular diseases, an elevated TyG index is associated with adverse short-term and long-term outcomes. Furthermore, in non-diabetic patients, an elevated TyG index is associated with adverse long-term prognosis.


Assuntos
Biomarcadores , Glicemia , Bases de Dados Factuais , Resistência à Insulina , Valor Preditivo dos Testes , Triglicerídeos , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Fatores de Risco , Glicemia/metabolismo , Medição de Risco , Fatores de Tempo , Biomarcadores/sangue , Triglicerídeos/sangue , Adulto , Prognóstico , Estado Terminal/mortalidade , Cuidados Críticos , Unidades de Terapia Intensiva , Procedimentos Cirúrgicos Operatórios/mortalidade , Procedimentos Cirúrgicos Operatórios/efeitos adversos , Estudos Retrospectivos , Resultados de Cuidados Críticos
3.
BMC Public Health ; 24(1): 180, 2024 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-38225648

RESUMO

BACKGROUND: The World Health Organization (WHO) has established recommended daily intakes for sodium and potassium. However, there is currently some controversy regarding the association between sodium intake, potassium intake, the sodium-to-potassium ratio, and overall mortality. To assess the correlations between sodium intake, potassium intake, the sodium-to-potassium ratio, and overall mortality, as well as the potential differences in sodium and potassium intake thresholds among different population groups, we analyzed data from NHANES 2003-2018. METHODS: NHANES is an observational cohort study that estimates sodium and potassium intake through one or two 24-h dietary recalls. Hazard ratios (HR) for overall mortality were calculated using multivariable adjusted Cox models accounting for sampling design. A total of 13855 out of 26288 participants were included in the final analysis. Restricted cubic spline analyses were used to examine the relationship between sodium intake, potassium intake, and overall mortality. If non-linearity was detected, we employed a recursive algorithm to calculate inflection points. RESULTS: Based on one or two 24-h dietary recalls, the sample consisted of 13,855 participants, representing a non-institutionalized population aged 40-80 years, totaling 11,348,771 person-months of mean follow-up 99.395 months. Daily sodium intake and daily potassium intake were inversely associated with all-cause mortality. Restrictive cubic spline analysis showed non-linear relationships between daily sodium intake, potassium intake, sodium-potassium ratio, and total mortality. The inflection point for daily sodium intake was 3133 mg/d, and the inflection point for daily potassium intake was 3501 mg/d, and the inflection point for daily sodium-potassium ratio intake was 1.203 mg/mg/d. In subgroup analyses, a significant interaction was found between age and high sodium intake, which was further confirmed by the smooth curves that showed a U-shaped relationship between sodium intake and all-cause mortality in the elderly population, with a inflection point of 3634 mg/d. CONCLUSION: Nonlinear associations of daily sodium intake, daily potassium intake and daily sodium-potassium ratio intake with all-cause mortality were observed in American individuals. The inflection point for daily sodium intake was 3133 mg/d. And the inflection point for daily sodium intake was 3634 mg/d in elderly population. The inflection point for daily potassium intake was 3501 mg/d. The inflection point for daily sodium-potassium ratio intake was 1.203 mg/mg/d, respectively, A healthy diet should be based on reasonable sodium intake and include an appropriate sodium-to-potassium ratio.


Assuntos
Sódio na Dieta , Sódio , Humanos , Idoso , Sódio na Dieta/análise , Inquéritos Nutricionais , Dieta , Potássio
4.
Blood ; 138(20): 1986-1997, 2021 11 18.
Artigo em Inglês | MEDLINE | ID: mdl-34098576

RESUMO

The erythropoietin receptor (EpoR) has traditionally been thought of as an erythroid-specific gene. Notably, accumulating evidence suggests that EpoR is expressed well beyond erythroid cells. However, the expression of EpoR in non-erythroid cells has been controversial. In this study, we generated EpoR-tdTomato-Cre mice and used them to examine the expression of EpoR in tissue macrophages and hematopoietic cells. We show that in marked contrast to the previously available EpoR-eGFPcre mice, in which a very weak eGFP signal was detected in erythroid cells, tdTomato was readily detectable in both fetal liver (FL) and bone marrow (BM) erythroid cells at all developmental stages and exhibited dynamic changes during erythropoiesis. Consistent with our recent finding that erythroblastic island (EBI) macrophages are characterized by the expression of EpoR, tdTomato was readily detected in both FL and BM EBI macrophages. Moreover, tdTomato was also detected in subsets of hematopoietic stem cells, progenitors, megakaryocytes, and B cells in BM as well as in spleen red pulp macrophages and liver Kupffer cells. The expression of EpoR was further shown by the EpoR-tdTomato-Cre-mediated excision of the floxed STOP sequence. Importantly, EPO injection selectively promoted proliferation of the EpoR-expressing cells and induced erythroid lineage bias during hematopoiesis. Our findings imply broad roles for EPO/EpoR in hematopoiesis that warrant further investigation. The EpoR-tdTomato-Cre mouse line provides a powerful tool to facilitate future studies on EpoR expression and regulation in various non-hematopoietic cells and to conditionally manipulate gene expression in EpoR-expressing cells for functional studies.


Assuntos
Expressão Gênica , Células-Tronco Hematopoéticas/metabolismo , Macrófagos/metabolismo , Receptores da Eritropoetina/genética , Animais , Células-Tronco Hematopoéticas/citologia , Humanos , Integrases/análise , Integrases/genética , Substâncias Luminescentes/análise , Substâncias Luminescentes/metabolismo , Proteínas Luminescentes/análise , Proteínas Luminescentes/genética , Macrófagos/citologia , Camundongos , Receptores da Eritropoetina/análise , Proteína Vermelha Fluorescente
5.
Blood ; 138(17): 1615-1627, 2021 10 28.
Artigo em Inglês | MEDLINE | ID: mdl-34036344

RESUMO

Histone deacetylases (HDACs) are a group of enzymes that catalyze the removal of acetyl groups from histone and nonhistone proteins. HDACs have been shown to have diverse functions in a wide range of biological processes. However, their roles in mammalian erythropoiesis remain to be fully defined. This study showed that, of the 11 classic HDAC family members, 6 (HDAC1, -2, -3, and HDAC5, -6, -7) are expressed in human erythroid cells, with HDAC5 most significantly upregulated during terminal erythroid differentiation. Knockdown of HDAC5 by either short hairpin RNA or small interfering RNA in human CD34+ cells followed by erythroid cell culture led to increased apoptosis, decreased chromatin condensation, and impaired enucleation of erythroblasts. Biochemical analyses revealed that HDAC5 deficiency resulted in activation of p53 in association with increased acetylation of p53. Furthermore, although acetylation of histone 4 (H4) is decreased during normal terminal erythroid differentiation, HDAC5 deficiency led to increased acetylation of H4 (K12) in late-stage erythroblasts. This increased acetylation was accompanied by decreased chromatin condensation, implying a role for H4 (K12) deacetylation in chromatin condensation. ATAC-seq and RNA sequencing analyses revealed that HDAC5 knockdown leads to increased chromatin accessibility genome-wide and global changes in gene expression. Moreover, pharmacological inhibition of HDAC5 by the inhibitor LMK235 also led to increased H4 acetylation, impaired chromatin condensation, and enucleation. Taken together, our findings have uncovered previously unrecognized roles and molecular mechanisms of action for HDAC5 in human erythropoiesis. These results may provide insights into understanding the anemia associated with HDAC inhibitor treatment.


Assuntos
Células Eritroides/citologia , Eritropoese , Histona Desacetilases/genética , Apoptose , Eritroblastos/citologia , Eritroblastos/metabolismo , Células Eritroides/metabolismo , Humanos , Interferência de RNA , RNA Interferente Pequeno/genética , Regulação para Cima
6.
Haematologica ; 108(9): 2487-2502, 2023 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-37021526

RESUMO

Enhancer of zeste homolog 2 (EZH2) is the lysine methyltransferase of polycomb repressive complex 2 (PRC2) that catalyzes H3K27 tri-methylation. Aberrant expression and loss-of-function mutations of EZH2 have been demonstrated to be tightly associated with the pathogenesis of various myeloid malignancies characterized by ineffective erythropoiesis, such as myelodysplastic syndrome (MDS). However, the function and mechanism of EZH2 in human erythropoiesis still remains largely unknown. Here, we demonstrated that EZH2 regulates human erythropoiesis in a stage-specific, dual-function manner by catalyzing histone and non-histone methylation. During the early erythropoiesis, EZH2 deficiency caused cell cycle arrest in the G1 phase, which impaired cell growth and differentiation. Chromatin immunoprecipitation sequencing and RNA sequencing discovered that EZH2 knockdown caused a reduction of H3K27me3 and upregulation of cell cycle proteindependent kinase inhibitors. In contrast, EZH2 deficiency led to the generation of abnormal nuclear cells and impaired enucleation during the terminal erythropoiesis. Interestingly, EZH2 deficiency downregulated the methylation of HSP70 by directly interacting with HSP70. RNA-sequencing analysis revealed that the expression of AURKB was significantly downregulated in response to EZH2 deficiency. Furthermore, treatment with an AURKB inhibitor and small hairpin RNAmediated AURKB knockdown also led to nuclear malformation and decreased enucleation efficiency. These findings strongly suggest that EZH2 regulates terminal erythropoiesis through a HSP70 methylation-AURKB axis. Our findings have implications for improved understanding of ineffective erythropoiesis with EZH2 dysfunction.


Assuntos
Proteína Potenciadora do Homólogo 2 de Zeste , Eritropoese , Histonas , Humanos , Proteína Potenciadora do Homólogo 2 de Zeste/genética , Eritropoese/genética , Histonas/metabolismo , Metilação , Complexo Repressor Polycomb 2/genética , Complexo Repressor Polycomb 2/metabolismo
7.
Phys Rev Lett ; 128(7): 076802, 2022 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-35244417

RESUMO

The Majorana search is caught up in an extensive debate about the false-positive signals from nontopological Andreev bound states. We introduce a remedy using the dissipative probe to generate electron-boson interaction. We theoretically show that the interaction-induced renormalization leads to significantly distinct universal zero-bias conductance behaviors, i.e., distinct characteristic power law in temperature, for different types of Andreev reflections, that show a sharp contrast to that of a Majorana zero mode. Various specific cases have been studied, including the cases in which two charges involved in an Andreev reflection process maintain or lose coherence, and the cases for multiple Andreev bound states with or without a Majorana. A transparent list of conductance features in each case is provided to help distinguish the observed subgap states in experiments, which also promotes the identification of Majorana zero modes.

8.
Phys Rev Lett ; 128(7): 076803, 2022 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-35244449

RESUMO

Hybrid semiconductor-superconductor nanowires are predicted to host Majorana zero modes that induce zero-bias peaks (ZBPs) in tunneling conductance. ZBPs alone, however, are not sufficient evidence due to the ubiquitous presence of Andreev bound states. Here, we implement a strongly resistive normal lead in InAs-Al nanowire devices and show that most of the expected Andreev bound state-induced ZBPs can be suppressed, a phenomenon known as environmental Coulomb blockade. Our result is the first experimental demonstration of this dissipative interaction effect on Andreev bound states and can serve as a possible filter to narrow down the ZBP phase diagram in future Majorana searches.

9.
Anal Bioanal Chem ; 413(16): 4227-4236, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34009443

RESUMO

In the present work, a structure-dependent ratiometric fluorescence (RF) sensor constructed with boric acid-modified carbon quantum dots (B-CQDs) and Tb-MOF(MOF-76) was developed for sensing 2,6-pyridinedicarboxylic acid (DPA). Based on the distinct fluorescent responses of B-CQDs and MOF-76 to DPA, MOF-76/B-CQDs can be developed as a RF sensor for DPA detection. In this RF sensor, the reticulated cross-linked structure of MOF-76/B-CQDs can be destroyed by DPA due to a strong coordination effect between DPA and the Tb of MOF-76, resulting in the quenching of the fluorescence of B-CQD and the restoration of the fluorescence of MOF-76 after the addition of DPA. Benefiting from the confinement effect of the special structure change, the presented sensor showed high sensitivity toward DPA with a detection limit of 3.05 µM and excellent selectivity over the monochromatic fluorescence sensor.

10.
Anal Bioanal Chem ; 413(26): 6571-6580, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34417645

RESUMO

Nanozymes were the novel research field to replace natural enzymes because of stability and low cost. However, the research on nanozymes was mainly focused on peroxidase, and there was little research about nanozymes with oxidase-like activity, especially mimic oxidase of small molecules related to human physiology. High levels of uric acid (UA) in the body can cause hyperuricemia and gout. And natural uricase cured this disease because it could oxidize UA. The oxidase-like activity of mixed valence state metal organic frameworks with cerium (MVSM) had been studied, but MVSM was found to have uricase-like activity in this article. The catalytic process of UA with MVSM was studied by a variety of analytical methods, which was similar to the natural uricase except for further oxidation of H2O2. The catalytic activity constants of MVSM were acquired by the Michaelis-Menten equation. MVSM had a better ability to catalyze UA in in vivo and in vitro experiments. An enzyme-free analysis-based mimic uricase for UA was established. All the experimental results proved that MVSM had a good prospect to replace the natural uricase. A nanomaterial, mixed valence state Ce-MOF (MVSM), with uricase-like activity has been found in vivo and in vitro. This material has potential to be a fluorescent analysis for detecting uric acid without uricase.


Assuntos
Cério/química , Estruturas Metalorgânicas/química , Urato Oxidase/química , Animais , Materiais Biomiméticos/química , Catálise , Humanos , Masculino , Camundongos , Oxirredução , Ácido Úrico/química
11.
Phytochem Anal ; 31(5): 535-544, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31849150

RESUMO

INTRODUCTION: The application of quality by design (QbD) concept needs to be strengthened in the field of traditional Chinese medicine research. The extraction process has an important influence on the effectiveness of the drug, and the combination of QbD and the extraction process of the active ingredient helps to improve the effectiveness of the drug. OBJECTIVE: To establish the extraction design space for ursolic acid (UA) from Paulowniae Flos based on the concept of QbD. METHODS: The extraction yield of the target component UA was taken as critical quality attributes (CQAs), extraction time, extraction temperature, ethanol concentration and liquid-solid ratio, as critical process parameters (CPPs). Box-Behnken design (BBD) was applied to optimise the design space and the chromatographic conditions were performed on a Shimadzu C18 reversed-phase column with 0.1% (v/v) acetic acid aqueous water-acetonitrile (7:13, v/v) as the mobile phase at a 1 mL/min flow rate, using UA standard as a control and detection at 210 nm. RESULTS: The single factor investigation and BBD experiment were used to construct the design space, while verification experiments and methodological validation were used to demonstrate that the space was robust and analytical methods were appropriate. The operating space of ethanol concentration 93-98%, liquid-solid ratio 28-37 mL/g and extraction temperature 70-78.3°C was recommended. CONCLUSION: The proposed methodology can help to promote the quality control of the Chinese medicine extraction process and facilitate the production operation of the enterprise easier.


Assuntos
Medicamentos de Ervas Chinesas , Triterpenos , Medicina Tradicional Chinesa , Controle de Qualidade , Ácido Ursólico
13.
Mikrochim Acta ; 186(12): 808, 2019 11 19.
Artigo em Inglês | MEDLINE | ID: mdl-31745649

RESUMO

ß-Cyclodextrin-functionalized carbon nitride nanosheets were modified with a molecularly imprinted polymer to obtain a fluorescent probe of type MIP@ß-CD/CNNS which is shown to enable fluorometric determination of sterigmatocystin (STG). The material was characterized by transmission electron microscopy, infrared spectra, powder X-ray diffraction, X-ray photoelectron spectroscopy, and by absorption and emission spectra. The modified CNNSs have a good fluorescence quantum yield (13%), high sorption capacity for STG (86 mg·g-1), fast adsorption rate (25 min), and superior adsorption selectivity (with an imprint factor 2.56). When used as an optical probe for STG, the CNNSs act as the chromophore, while ß-CD and MIP act as the recognition groups. The blue fluorescence of MIP@ß-CD/CNNS (with excitation/emission maxima at 368/432 nm) is quenched by STG. Fluorescence drops linearly in the 0.15 to 3.1 µM STG concentration range. The lower detection limit is 74 nM. The method was successfully applied to the determination of STG in spiked wheat extract. Conceivably, this detection scheme based on a combination of ß-CD inclusion and molecular imprinting may be extended to the detection of various other organic compounds. Graphical abstractSchematic representation of the preparation of surface-imprinted ß-cyclodextrin-functionalized carbon nitride nanosheets. These are used, along with a molecularly imprinted polymer, for fluorometric determination of sterigmatomycin.


Assuntos
Corantes Fluorescentes/química , Micotoxinas/análise , Nanoestruturas/química , Nitrilas/química , Espectrometria de Fluorescência/métodos , beta-Ciclodextrinas/química , Adsorção , Antraquinonas/química , Contaminação de Alimentos/análise , Limite de Detecção , Impressão Molecular , Micotoxinas/química , Triticum/química
14.
Phys Rev Lett ; 119(7): 075301, 2017 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-28949693

RESUMO

We derive the phonon dynamics of magnetic metals in the presence of strong spin-orbit coupling. We show that both a dissipationless viscosity and a dissipative viscosity arise in the dynamics. While the dissipationless viscosity splits the dispersion of left-handed and right-handed circularly polarized phonons, the dissipative viscosity damps them differently, inducing circular phonon dichroism. The effect offers a new degree of manipulation of phonons, i.e., the control of the phonon polarization. We investigate the effect in Weyl semimetals. We find that there exists strong circular phonon dichroism in Weyl semimetals breaking both the time-reversal and the inversion symmetry, making them potential materials for realizing the acoustic circular polarizer.

15.
Anal Bioanal Chem ; 409(17): 4157-4166, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28516278

RESUMO

Although stir bar sportive extraction was thought to be a highly efficiency and simple pretreatment approach, its wide application was limited by low selectivity, short service life, and relatively high cost. In order to improve the performance of the stir bar, molecular imprinted polymers and magnetic carbon nanotubes were combined in the present study. In addition, two monomers were utilized to intensify the selectivity of molecularly imprinted polymers. Fourier transform infrared spectroscopy, scanning electron microscopy, and selectivity experiments showed that the molecularly imprinted polymeric stir bar was successfully prepared. Then micro-extraction based on the obtained stir bar was coupled with HPLC for determination of trace cefaclor and cefalexin in environmental water. This approach had the advantages of stir bar sportive extraction, high selectivity of molecular imprinted polymers, and high sorption efficiency of carbon nanotubes. To utilize this pretreatment approach, pH, extraction time, stirring speed, elution solvent, and elution time were optimized. The LOD and LOQ of cefaclor were found to be 3.5 ng · mL-1 and 12.0 ng · mL-1, respectively; the LOD and LOQ of cefalexin were found to be 3.0 ng · mL-1 and 10.0 ng · mL-1, respectively. The recoveries of cefaclor and cefalexin were 86.5 ~ 98.6%. The within-run precision and between-run precision were acceptable (relative standard deviation <7%). Even when utilized in more than 14 cycles, the performance of the stir bar did not decrease dramatically. This demonstrated that the molecularly imprinted polymeric stir bar based micro-extraction was a convenient, efficient, low-cost, and a specific method for enrichment of cefaclor and cefalexin in environmental samples.


Assuntos
Antibacterianos/análise , Cefaclor/análise , Cefalexina/análise , Monitoramento Ambiental/métodos , Impressão Molecular/métodos , Microextração em Fase Sólida/métodos , Poluentes Químicos da Água/análise , Adsorção , Antibacterianos/isolamento & purificação , Cefaclor/isolamento & purificação , Cefalexina/isolamento & purificação , Cromatografia Líquida de Alta Pressão/métodos , Lagos/análise , Nanotubos de Carbono/química , Polímeros/química , Água/análise , Poluentes Químicos da Água/isolamento & purificação
17.
IEEE Trans Cybern ; PP2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38557610

RESUMO

In this article, a novel approach of prescribed performance synchronization control is developed for heterogeneous nonlinear multiagent systems (MASs) subject to unknown actuator faults. Considering that not all followers are able to access the information of the leader, a distributed auxiliary perception system is proposed to estimate the state information of the leader to guarantee that the estimation errors converge to zero within fixed time. Then, based on the estimated states, a prescribed performance fault-tolerant control (FTC) approach is proposed, which achieves the user-defined performance specifications even in the presence of system faults. Moreover, as accurate system dynamic models are perhaps hard to acquire in practical engineering, a data-based method is proposed by using the reinforcement learning (RL) algorithm to design the fault-tolerant controller, which only needs the off-policy online data and is independent of the model dynamics of followers. The stability and synchronization with the prescribed behavior are guaranteed through the Lyapunov stability theorem. Finally, simulation results are presented to illustrate the effectiveness of the developed controller.

18.
Foods ; 13(9)2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38731776

RESUMO

This paper reports the preparation of margarine fat using Lipozyme TL IM as a catalyst and peony seed oil (PSO), palm stearin (PS) and coconut oil (CO) as raw materials. The results indicate that there were no significant changes in fatty acid composition before or after interesterification of the oil samples. However, the total amount of medium- and long-chain triglycerides (MLCTs) increased from 2.92% to 11.38% in sample E1 after interesterification, mainly including LaLaO, LaMO, LaPM, LaOO, LaPO and LaPP. Moreover, the slip melting point (SMP) of sample E1 decreased from 45.9 °C (B1) to 33.5 °C. The solid fat content (SFC) of all the samples at 20 °C was greater than 10%, indicating that they could effectively prevent oil exudation. After interesterification, the samples exhibited a ß' crystal form and could be used to prepare functional margarine.

19.
Adv Sci (Weinh) ; 11(13): e2309293, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38258489

RESUMO

The efficiency of photocatalytic hydrogen evolution is currently limited by poor light adsorption, rapid recombination of photogenerated carriers, and ineffective surface reaction rate. Although heterojunctions with innovative morphologies and structures can strengthen built-in electric fields and maximize the separation of photogenerated charges. However, how to rational design of novel multidimensional structures to simultaneously improve the above three bottleneck problems is still a research imperative. Herein, a unique Cu2O─S@graphene oxide (GO)@Zn0.67Cd0.33S Three dimensional (3D) hollow heterostructure is designed and synthesized, which greatly extends the carrier lifetime and effectively promotes the separation of photogenerated charges. The H2 production rate reached 48.5 mmol g-1 h-1 under visible light after loading Ni2+ on the heterojunction surface, which is 97 times higher than that of pure Zn0.67Cd0.33S nanospheres. Furthermore, the H2 production rate can reach 77.3 mmol g-1 h-1 without cooling, verifying the effectiveness of the photothermal effect. Meanwhile, in situ characterization and density flooding theory calculations reveal the efficient charge transfer at the p-n 3D hollow heterojunction interface. This study not only reveals the detailed mechanism of photocatalytic hydrogen evolution in depth but also rationalizes the construction of superior 3D hollow heterojunctions, thus providing a universal strategy for the materials-by-design of high-performance heterojunctions.

20.
ACS Appl Mater Interfaces ; 16(13): 16678-16686, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38503721

RESUMO

Photodetectors with a broad-band response range are widely used in many fields and are regarded as pivotal components of the modern miniaturized electronics industry. However, commercial broad-band photodetectors composed of traditional bulk semiconductor materials are still limited by complex preparation techniques, high costs, and a lack of mechanical strength and flexibility, which are difficult to satisfy the increasing demand for flexible and wearable optoelectronics. Therefore, researchers have been devoted to finding new strategies to obtain flexible, stable, and high-performance broad-band photodetectors. In this work, a novel self-assembled BiGaSeAs composite superlattice-structured nanowire was developed with a simple chemical vapor deposition method for easy fabrication. After the device assembling, the photodetector showed outstanding performance in terms of obvious Ion/Ioff (13.9), broad-band photoresponse (365-940 nm), excellent responsivity (1007.67 A/W), high detectivity (9.38 × 109 Jones), and rapid response (21 and 23 ms). The formation of microheterojunctions among various materials inside the nanowires also contributed to their extended broad-spectrum response and outstanding detection ability. These results indicate that the BiGaSeAs nanowires have potential applications in the field of flexible and wearable electronics.

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