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1.
Angew Chem Int Ed Engl ; : e202409563, 2024 Jul 01.
Article in English | MEDLINE | ID: mdl-38949085

ABSTRACT

Regulating the binding effect between the surface of an electrode material and reaction intermediates is essential in highly efficient CO2 electro-reduction to produce high-value multicarbon (C2+) compounds. Theoretical study reveals that lattice tensile strain in single-component Cu catalysts can reduce the dipole-dipole repulsion between *CO intermediates and promotes *OH adsorption, and the high *CO and *OH coverage decreases the energy barrier for C-C coupling. In this work, Cu catalysts with varying lattice tensile strain were fabricated by electro-reducing CuO precursors with different crystallinity, without adding any extra components. The as-prepared single-component Cu catalysts were used for CO2 electro-reduction, and it is discovered that the lattice tensile strain in Cu could enhance the Faradaic efficiency (FE) of C2+ products effectively. Especially, the as-prepared CuTPA catalyst with high lattice tensile strain achieves a FEC2+ of 90.9% at -1.25 V vs. RHE with a partial current density of 486.1 mA cm-2.

2.
Adv Colloid Interface Sci ; 329: 103162, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38761601

ABSTRACT

This paper reviews the recent progress of small angle scattering (SAS) techniques, mainly including X-ray small angle scattering technique (SAXS) and neutron small angle scattering (SANS) technique, in the study of metal-organic framework (MOF) colloidal materials (CMOFs). First, we introduce the application research of SAXS technique in pristine MOFs materials, and review the studies on synthesis mechanism of MOF materials, the pore structures and fractal characteristics, as well as the spatial distribution and morphological evolution of foreign molecules in MOF composites and MOF-derived materials. Then, the applications of SANS technique in MOFs are summarized, with emphasis on SANS data processing method, structure modeling and quantitative structural information extraction. Finally, the characteristics and developments of SAS techniques are commented and prospected. It can be found that most studies on MOF materials with SAS techniques focus mainly on nanoporous structure characterization and the evolution of pore structures, or the spatial distribution of other foreign molecules loaded in MOFs. Indeed, SAS techniques take an irreplaceable role in revealing the structure and evolution of nanopores in CMOFs. We expect that this paper will help to understand the research status of SAS techniques on MOF materials and better to apply SAS techniques to conduct further research on MOF and related materials.

3.
J Am Chem Soc ; 146(23): 15917-15925, 2024 Jun 12.
Article in English | MEDLINE | ID: mdl-38805725

ABSTRACT

Cu-based catalysts are optimal for the electroreduction of CO2 to generate hydrocarbon products. However, controlling product distribution remains a challenging topic. The theoretical investigations have revealed that the coordination number (CN) of Cu considerably influences the adsorption energy of *CO intermediates, thereby affecting the reaction pathway. Cu catalysts with different CNs were fabricated by reducing CuO precursors via cyclic voltammetry (Cyc-Cu), potentiostatic electrolysis (Pot-Cu), and pulsed electrolysis (Pul-Cu), respectively. High-CN Cu catalysts predominantly generate C2+ products, while low-CN Cu favors CH4 production. For instance, over the high-CN Pot-Cu, C2+ is the main product, with the Faradaic efficiency (FE) reaching 82.5% and a partial current density (j) of 514.3 mA cm-2. Conversely, the low-CN Pul(3)-Cu favors the production of CH4, achieving the highest FECH4 value of 56.7% with a jCH4 value of 234.4 mA cm-2. In situ X-ray absorption spectroscopy and Raman spectroscopy studies further confirm the different *CO adsorptions over Cu catalysts with different CN, thereby directing the reaction pathway of the CO2RR.

4.
J Clin Ultrasound ; 2024 May 28.
Article in English | MEDLINE | ID: mdl-38804714

ABSTRACT

BACKGROUND: Recent studies have shown that right atrial (RA) function are important predictors of cardiovascular morbidity and mortality. However, the study data about RA phasic function in obstructive sleep apnea syndrome (OSAS) patients are scarce, especially based on the left ventricular geometry. So, we aimed to assess the influence of left ventricular geometry on RA phasic function in OSAS patients via a multimodal echocardiographic approach. METHODS: Total of 235 OSAS patients were enrolled in this cross-section study and underwent complete clinical, polysomnography, and echocardiography examinations. The OSAS patients were divided into four groups based on left ventricular mass index (LVMI) and relative wall thickness (RWT): normal geometry (NG), concentric remodeling (CR), concentric hypertrophy (CH), and eccentric hypertrophy (EH). RA phasic function was evaluated via multimodal echocardiography approach (two-dimensional echocardiography biplane method [2DE]; two-dimensional speckle-tracking echocardiography [2D-STE]; and three-dimensional echocardiography [3DE]). The multiple linear regression analysis was used to determine the relationship between left ventricular geometry and RA phasic function. RESULTS: The RA volume and indices increased from NG to CR to EH to CH. RA total emptying fraction and RA strain during systole decreased from NG to CR to EH to CH. RA passive emptying fraction and RA strain during early diastole similarly decreased. RA active emptying fraction and RA strain during late diastole also gradually increased similarly. In analyses that adjusted for gender, age, body mass index, systolic blood pressure, apnea-hypopnea index, LVMI, systolic pulmonary artery pressure, and right ventricular free wall thickness, CH was associated with RA reservoir and conduit function via 2DE area-length method, whereas CH and EH were associated with RA reservoir and conduit function via 2D-STE and 3DE method. Further, CH was associated with RA booster pump function via 2DE area-length method, 2D-STE, and 3DE method. CONCLUSION: The RA volumes and phasic function varied with left ventricular geometry via multimodal echocardiography approach. CH had the apparent negative effect on RA phasic function.

5.
Materials (Basel) ; 17(5)2024 Feb 29.
Article in English | MEDLINE | ID: mdl-38473611

ABSTRACT

As a candidate anode material for Li-ion batteries, Bi-based materials have attracted extensive attention from researchers due to their high specific capacity, environmental friendliness, and simple synthesis methods. However, Bi-based anode materials are prone to causing large volume changes during charging and discharging processes, and the effect of these changes on lithium storage performance is still unclear. This work introduces that Bi/C nanocomposites are prepared by the Bi-based MOF precursor calcination method, and that the Bi/C nanocomposite maintains a high specific capacity (931.6 mAh g-1) with good multiplicative performance after 100 cycles at a current density of 100 mA g-1. The structural evolution of Bi/C anode material during the first cycle of charging and discharging is investigated using in situ synchrotron radiation SAXS. The SAXS results indicate that the multistage scatterers of Bi/C composite, used as an anode material during the first lithiation, can be classified into mesopores, interspaces, and Bi nanoparticles. The different nanostructure evolutions of three types of Bi nanoparticles were observed. It is believed that this result will help to further understand the complex reaction mechanism of Bi-based anode materials in Li-ion batteries.

6.
J Am Chem Soc ; 146(14): 10084-10092, 2024 Apr 10.
Article in English | MEDLINE | ID: mdl-38530325

ABSTRACT

Glycine is a nonessential amino acid that plays a vital role in various biological activities. However, the conventional synthesis of glycine requires sophisticated procedures or toxic feedstocks. Herein, we report an electrochemical pathway for glycine synthesis via the reductive coupling of oxalic acid and nitrate or nitrogen oxides over atomically dispersed Fe-N-C catalysts. A glycine selectivity of 70.7% is achieved over Fe-N-C-700 at -1.0 V versus RHE. Synergy between the FeN3C structure and pyrrolic nitrogen in Fe-N-C-700 facilitates the reduction of oxalic acid to glyoxylic acid, which is crucial for producing glyoxylic acid oxime and glycine, and the FeN3C structure could reduce the energy barrier of *HOOCCH2NH2 intermediate formation thus accelerating the glyoxylic acid oxime conversion to glycine. This new synthesis approach for value-added chemicals using simple carbon and nitrogen sources could provide sustainable routes for organonitrogen compound production.

7.
Angew Chem Int Ed Engl ; 63(2): e202313796, 2024 Jan 08.
Article in English | MEDLINE | ID: mdl-38015565

ABSTRACT

Modulation of the microenvironment on the electrode surface is one of the effective means to improve the efficiency of electrocatalytic carbon dioxide reduction (eCO2 RR). To achieve high conversion rates, the phase boundary at the electrode surface should be finely controlled to overcome the limitation of CO2 solubility in the aqueous electrolyte. Herein, we developed a simple and efficient method to structure electrocatalyst with a superhydrophobic surface microenvironment by one-step co-electrodeposition of Cu and polytetrafluoroethylene (PTFE) on carbon paper. The super-hydrophobic Cu-based electrode displayed a high ethylene (C2 H4 ) selectivity with a Faraday efficiency (FE) of 67.3 % at -1.25 V vs. reversible hydrogen electrode (RHE) in an H-type cell, which is 2.5 times higher than a regular Cu electrode without PTFE. By using PTFE as a surface modifier, the activity of eCO2 RR is enhanced and water (proton) adsorption is inhibited. This strategy has the potential to be applied to other gas-conversion electrocatalysts.

8.
Adv Mater ; 36(11): e2310273, 2024 Mar.
Article in English | MEDLINE | ID: mdl-37974514

ABSTRACT

Cu2+ -based materials, a class of promising catalysts for the electrocatalytic carbon dioxide reduction reaction (CO2 RR) to value-added chemicals, usually undergo inevitable and uncontrollable reorganization processes during the reaction, resulting in catalyst deactivation or the new active sites formation and bringing great challenges to exploring their structure-performance relationships. Herein, a facile strategy is reported for constructing Cu2+ and 3, 4-ethylenedioxythiophene (EDOT) coordination to stabilize Cu2+ ions to prepare a novel layered coordination polymer (CuPEDOT). CuPEDOT enables selective reduction of CO2 to CH4 with 62.7% Faradaic efficiency at the current density of 354 mA cm-2 in a flow cell, and the catalyst is stable for at least 15 h. In situ spectroscopic characterization and theoretical calculations reveal that CuPEDOT catalyst can maintain the Cu2+ -EDOT coordination structurally stable in CO2 RR and significantly promote the further hydrogenation of *CO intermediates, favoring the formation of CH4 instead of dimerization to C2 products. The strong coordination between EDOT and Cu2+ prevents the reduction of Cu2+ ions during CO2 RR. The finding of this work provides a new perspective on designing molecularly stable, highly active catalysts for CO2 RR.

9.
J Clin Ultrasound ; 52(3): 241-248, 2024.
Article in English | MEDLINE | ID: mdl-38041410

ABSTRACT

OBJECTIVE: Tumor necrosis factor-α (TNF-α) can induce left ventricular remodeling. In this study, we investigated whether the TNF-α-308G>A polymorphism is associated with left ventricular geometry (LVG) and left ventricular functional abnormalities in obstructive sleep apnea (OSA) subjects. METHODS: Two hundred and seventy-eight subjects were enrolled. Echocardiography and genetic data were assessed in all patients. Geometric patterns of the left ventricle were determined from the relative wall thickness and left ventricular mass index (LVMI). Genetic analysis for the TNF-α-308G>A SNP rs1800629 was identified by Sanger sequencing. The correlations of the TNF-α-308G>A polymorphism with LVG and left ventricular function were analyzed by difference analysis and logistic regression. RESULTS: The chi-square test showed that there were differences in genotype distributions among the four groups (p = 0.033), such that the frequency of GA+AA genotypes was significantly higher in the concentric hypertrophy group than in the normal geometry group (p < 0.05). Independent sample T tests showed that the GA+AA genotypes had higher IVST, LVPWT, LVMI, E/e' values, and lower e' values than those of the GG genotype (p < 0.05). Logistic regression analysis showed that the TNF-α-308G>A polymorphism was independently correlated with eccentric hypertrophy (OR = 2.456, p = 0.047) and concentric hypertrophy (OR = 2.456, p = 0.047). CONCLUSION: In OSA patients, the TNF-α-308G>A polymorphism was linked to LVG and abnormal left ventricular diastolic function, suggesting that the TNF-α-308G>A polymorphism may have an important influence on LVG alterations.


Subject(s)
Sleep Apnea, Obstructive , Tumor Necrosis Factor-alpha , Humans , Heart Ventricles/diagnostic imaging , Hypertrophy, Left Ventricular , Polymorphism, Genetic , Sleep Apnea, Obstructive/genetics , Sleep Apnea, Obstructive/complications , Tumor Necrosis Factor-alpha/genetics
10.
J Clin Ultrasound ; 52(1): 20-29, 2024 Jan.
Article in English | MEDLINE | ID: mdl-37883130

ABSTRACT

AIMS: Cardiac left ventricular hypertrophy (LVH) is the most common manifestation of heart involvement in Anderson-Fabry disease (AFD). Conventional cardiac imaging is not sensitive enough to detect early signs of LVH in AFD. It remains uncertain whether enzyme replacement therapy (ERT) can prevent LVH progression and improve myocardial function. This study aimed to assess the effectiveness of two-dimensional speckle tracking echocardiography (2D-STE) in early detection of cardiac involvement in AFD and monitoring the efficacy of agalsidase alfa and agalsidase beta therapy. METHODS AND RESULTS: Thirteen consecutive AFD patients and 12 healthy controls underwent standard transthoracic 2D, color Doppler, tissue Doppler echocardiography, and 2D strain analysis. Global longitudinal strain (GLS) and global circumferential strain (GCS) were measured. Diastolic strain rate (SR) was extracted. Compared to healthy subjects, AFD patients without LVH showed lower levels of GLS (p < 0.001) and SR (p = 0.01), while there was no difference in GCS (p = 0.82). Following treatment, apical circumferential strain (ACS) showed improvement (p = 0.01). CONCLUSION: In AFD patients without LVH, there was a decrease in global and segmental LS. Higher plasma Lyso-GL-3 concentrations were associated with elevated ACS values after ERT, indicating that ACS in AFD patients without LVH, albeit normal, is involved in early LV dysfunction.


Subject(s)
Fabry Disease , Ventricular Dysfunction, Left , Humans , Fabry Disease/complications , Fabry Disease/diagnostic imaging , Fabry Disease/drug therapy , Enzyme Replacement Therapy , Hypertrophy, Left Ventricular/diagnostic imaging , Echocardiography/methods , Heart Ventricles/diagnostic imaging , Ventricular Dysfunction, Left/complications , Ventricular Dysfunction, Left/diagnostic imaging , Ventricular Dysfunction, Left/drug therapy , Ventricular Function, Left
11.
Chem Sci ; 14(48): 14308-14315, 2023 Dec 13.
Article in English | MEDLINE | ID: mdl-38098726

ABSTRACT

The electrochemical reduction of carbon dioxide (CO2RR) holds great promise for sustainable energy utilization and combating global warming. However, progress has been impeded by challenges in developing stable electrocatalysts that can steer the reaction toward specific products. This study proposes a carbon shell coating protection strategy by an efficient and straightforward approach to prevent electrocatalyst reconstruction during the CO2RR. Utilizing a copper-based metal-organic framework as the precursor for the carbon shell, we synthesized carbon shell-coated electrocatalysts, denoted as Cu-x-y, through calcination in an N2 atmosphere (where x and y represent different calcination temperatures and atmospheres: N2, H2, and NH3). It was found that the faradaic efficiency of ethanol over the catalysts with a carbon shell could reach ∼67.8%. In addition, the catalyst could be stably used for more than 16 h, surpassing the performance of Cu-600-H2 and Cu-600-NH3. Control experiments and theoretical calculations revealed that the carbon shell and Cu-C bonds played a pivotal role in stabilizing the catalyst, tuning the electron environment around Cu atoms, and promoting the formation and coupling process of CO*, ultimately favoring the reaction pathway leading to ethanol formation. This carbon shell coating strategy is valuable for developing highly efficient and selective electrocatalysts for the CO2RR.

12.
Chem Sci ; 14(41): 11474-11480, 2023 Oct 25.
Article in English | MEDLINE | ID: mdl-37886083

ABSTRACT

The construction of metal hetero-interfaces has great potential in the application of electro-catalytic carbon dioxide reduction (ECR). Herein, we report a fast, efficient, and simple electrodeposition strategy for synthesizing three-dimensional (3D) porous Cu/Zn heterostructures using the hydrogen bubble template method. When the deposition was carried out at -1.0 A for 30 s, the obtained 3D porous Cu/Zn heterostructures on carbon paper (CP) demonstrated a nearly 100% CO faradaic efficiency (FE) with a high partial current density of 91.8 mA cm-2 at -2.1 V vs. Ag/Ag+ in the mixed electrolyte of ionic liquids/acetonitrile in an H-type cell. In particular, the partial current density of CO could reach 165.5 mA cm-2 and the FE of CO could remain as high as 94.3% at -2.5 V vs. Ag/Ag+. The current density is much higher than most reported to date in an H-type cell (Table S1). Experimental and density functional theory (DFT) calculations reveal that the outstanding electrocatalytic performance of the electrode can be ascribed to the formation of 3D porous Cu/Zn heterostructures, in which the porous and self-supported architecture facilitates diffusion and the Cu/Zn heterostructures can reduce the energy barrier for ECR to CO.

13.
Sci Bull (Beijing) ; 68(20): 2362-2369, 2023 Oct 30.
Article in English | MEDLINE | ID: mdl-37657973

ABSTRACT

Efficient electrode design is crucial for the electrochemical reduction of CO2 to produce valuable chemicals. The solution used for the preparation of electrodes can affect their overall properties, which in turn determine the reaction efficiency. In this work, we report that transition metal salts could induce the change of two-phase ionic liquid/ethanol mixture into miscible one phase. Pre-phase separation region near the phase boundary of the ternary system was observed. Zinc nanoparticles were electro-deposited along the fibres of carbon paper (CP) substrate uniformly in the salt-induced pre-phase separation region solution. The as-prepared Zn(1)/CP electrode exhibits super-wettability to the electrolyte, rendering very high catalytic performance for CO2 electro-reduction, and the Faradaic efficiency towards CO is 97.6% with a current density of 340 mA cm-2, which is the best result to date in an H-type cell.

14.
Angew Chem Int Ed Engl ; 62(43): e202307952, 2023 Oct 23.
Article in English | MEDLINE | ID: mdl-37665252

ABSTRACT

The renewable-energy-powered electroreduction of nitrate (NO3 - ) to ammonia (NH3 ) has garnered significant interest as an eco-friendly and promising substitute for the Haber-Bosch process. However, the sluggish kinetics hinders its application at a large scale. Herein, we first calculated the N-containing species (*NO3 and *NO2 ) binding energy and the free energy of the hydrogen evolution reaction over Cu with different metal dopants, and it was shown that Zn was a promising candidate. Based on the theoretical study, we designed and synthesized Zn-doped Cu nanosheets, and the as-prepared catalysts demonstrated excellent performance in NO3 - -to-NH3 . The maximum Faradaic efficiency (FE) of NH3 could reach 98.4 % with an outstanding yield rate of 5.8 mol g-1 h-1 , which is among the best results up to date. The catalyst also had excellent cycling stability. Meanwhile, it also presented a FE exceeding 90 % across a wide potential range and NO3 - concentration range. Detailed experimental and theoretical studies revealed that the Zn doping could modulate intermediates adsorption strength, enhance NO2 - conversion, change the *NO adsorption configuration to a bridge adsorption, and decrease the energy barrier, leading to the excellent catalytic performance for NO3 - -to-NH3 .

15.
J Am Chem Soc ; 145(31): 17253-17264, 2023 Aug 09.
Article in English | MEDLINE | ID: mdl-37498730

ABSTRACT

The electrochemical CO2 reduction reaction (CO2RR) using renewable electricity is one of the most promising strategies for reaching the goal of carbon neutrality. Multicarbonous (C2+) products have broad applications, and ethanol is a valuable chemical and fuel. Many Cu-based catalysts have been reported to be efficient for the electrocatalytic CO2RR to C2+ products, but they generally offer limited selectivity and current density toward ethanol. Herein, we proposed a silica-mediated hydrogen-bonded organic framework (HOF)-templated approach to preparing ultrahigh-density Cu single-atom catalysts (SACs) on thin-walled N-doped carbon nanotubes (TWN). The content of Cu in the catalysts prepared by this method could be up to 13.35 wt %. It was found that the catalysts showed outstanding performance for the electrochemical CO2RR to ethanol, and the Faradaic efficiency (FE) of ethanol increased with the increase in Cu-N3 site density. The FE of ethanol over the catalysts with 13.35 wt % Cu could reach ∼81.9% with a partial current density of 35.6 mA cm-2 using an H-type cell, which is the best result for electrochemical CO2RR to ethanol to date. In addition, the catalyst could be stably used for more than 25 h. Experimental and density functional theory (DFT) studies revealed that the adjacent Cu-N3 active sites (one Cu atom coordinates with three N) were the active sites for the reaction, and their high density was crucial for the high FE of ethanol because the adjacent Cu-N3 sites with a short distance could promote the C-C coupling synergistically.

16.
J Am Chem Soc ; 145(21): 11512-11517, 2023 May 31.
Article in English | MEDLINE | ID: mdl-37196054

ABSTRACT

Using bulk metals as catalysts to get high efficiency in electro-reduction of CO2 is ideal but challenging. Here, we report the coupling of bulk metal electrodes and a ternary ionic-liquid-based electrolyte, 1-butyl-3-methylimidazolium tetrafluoroborate/1-dodecyl-3-methylimidazolium tetrafluoroborate/MeCN to realize highly efficient electro-reduction of CO2 to CO. Over various bulk metal electrodes, the ternary electrolyte not only increases the current density but also suppresses the hydrogen evolution reaction to obtain a high Faradaic efficiency (FE) toward CO. FECO could maintain ∼100% over a wide potential range, and metal electrodes showed very high stability in the ternary electrolyte. It is demonstrated that the aggregation behavior of the ternary electrolyte and the arrangement of two kinds of IL cations with different chain lengths in the electrochemical double layer not only increase the wettability to electrode and CO2 adsorption but also extend the diffusion channel of H+, rendering the high current density and FECO.

17.
Inorg Chem ; 62(10): 4385-4391, 2023 Mar 13.
Article in English | MEDLINE | ID: mdl-36857465

ABSTRACT

In recent years, the synthesis, crystalline structure, and applications of zeolite imidazole frameworks (ZIFs) have attracted extensive attention. Since the ZIF-L phase was synthesized, a new phase was observed during the heating process, but its crystal structure is unknown. The unknown new phase, which was named ZIF-L300 in this study, was confirmed again. In this study, the X-ray powder diffraction technique and Rietveld refinement were used to solve the crystalline structure of the unknown ZIF-L300 phase. The results demonstrate that ZIF-L300 has the same chemical formula (ZnC8N4H10) as in ZIF-8 and belongs to a hexagonal structure with a space group of P61. The lattice parameters have been determined as follows: a = b = 8.708(7) Å, c = 24.195(19) Å, α = ß = 90°, and γ = 120°. The X-ray absorption fine structure (XAFS) technique was also used to extract the local atomic structures. The in situ X-ray diffraction (XRD) technique was used to monitor the structural evolution of the as-prepared ZIF-L in a temperature range from room temperature to 600 °C. The results show that the sample experiences a change process from the initial ZIF-L orthorhombic phase (<210 °C), to the ZIF-L300 hexagonal phase (∼300 °C), then to an amorphous phase (∼390 °C), and finally to a zincite ZnO phase (>420 °C). These sorts of structural information are helpful to the application of ZIF materials and enrich the knowledge of the thermal stability of ZIF materials.

18.
Nat Commun ; 14(1): 1092, 2023 Feb 25.
Article in English | MEDLINE | ID: mdl-36841816

ABSTRACT

Amorphous nano-metal catalysts often exhibit appealing catalytic properties, because the intrinsic linear scaling relationship can be broken. However, accurate control synthesis of amorphous nano-metal catalysts with desired size and morphology is a challenge. In this work, we discover that Cu(0) could be oxidized to amorphous CuxO species by supercritical CO2. The formation process of the amorphous CuxO is elucidated with the aid of machine learning. Based on this finding, a method to prepare Cu nanoparticles with an amorphous shell is proposed by supercritical CO2 treatment followed by electroreduction. The unique feature of this method is that the size of the particles with amorphous shell can be easily controlled because their size depends on that of the original crystal Cu nanoparticles. Moreover, the thickness of the amorphous shell can be easily controlled by CO2 pressure and/or treatment time. The obtained amorphous Cu shell exhibits high selectivity for C2+ products with the Faradaic efficiency of 84% and current density of 320 mA cm-2. Especially, the FE of C2+ oxygenates can reach up to 65.3 %, which is different obviously from the crystalline Cu catalysts.

19.
J Clin Ultrasound ; 51(4): 603-609, 2023 May.
Article in English | MEDLINE | ID: mdl-36444874

ABSTRACT

INTRODUCTION: To investigate the relationship of superoxide dismutase (SOD) and malondialdehyde (MDA) levels with left ventricular geometry (LVG) and function in patients with primary hypertension (PH). METHODS: A total of 222 PH patients and 25 healthy control (HC)s were enrolled in this study. All subjects underwent echocardiography and blood biochemical examination. PH patients were divided into four groups based on Ganau classification: normal geometry (NG) group, concentric remodeling (CR) group, eccentric hypertrophy (EH) group, and concentric hypertrophy (CH) group. Pearson correlation analysis and logistic regression analysis were used to analyze the relationship between SOD and MDA with left ventricular structure and function. RESULTS: Compared to the HC, NG and CR groups, MDA level was higher while SOD level was lower in the EH and CH groups (all P < 0.001). SOD level was negatively correlated with IVSd, LVDd, LVPW, and global longitudinal strain (GLS), but positively correlated with LVEF. MDA level was positively correlated with IVSd, LVPW, and GLS, while negatively correlated with e'/a' and LVEF. SOD and MDA were independently associated with CR (OR = 0.970, P = 0.003; OR = 1.204, P = 0.043), EH (OR = 0.879, P < 0.001; OR = 2.197, P = 0.001) and CH (OR = 0.796, P < 0.001; OR = 3.669, P < 0.001). CONCLUSION: The SOD and MDA levels were correlated with LVG and function in PH patients. SOD and MDA may be important influencing factors of LVG change.


Subject(s)
Hypertension , Humans , Echocardiography , Essential Hypertension , Heart Ventricles/diagnostic imaging , Hypertension/complications , Hypertrophy, Left Ventricular/diagnostic imaging , Ventricular Function, Left , Superoxide Dismutase/metabolism
20.
J Colloid Interface Sci ; 629(Pt B): 1015-1026, 2023 Jan.
Article in English | MEDLINE | ID: mdl-36208602

ABSTRACT

Regulating electronic structure and enriching active sites of photocatalysts are effective strategies to promote hydrogen evolution. Herein, a unique NixCd1-xS-Ni0 photocatalyst, including the surface nickel (Ni) doping and atomic Ni0 anchoring sites, is successfully prepared by Ni2+ ions exchange reaction (Ni2++ CdS â†’ NixCd1-xS) and in-situ photo-induction of Ni0(Ni2++NixCd1-xS→hνNixCd1-xS-Ni0), respectively. As to Ni doping, the Ni replaced cadmium (Cd) atoms introduce hybridized states around the Fermi level, modulating the electronic structure of adjacent S atoms and optimizing the photocatalytic activity of sulfur (S) atoms. Besides, photogenerated Ni0 atoms, anchored on unsaturated S atoms, act as charge transfer bridges to reduce Ni2+ ions in the solution to Ni clusters (NixCd1-xS-Ni0→ne-NixCd1-xS-Ni). Subsequently, the displacement reaction of Ni clusters with protons (H+) spontaneously proceeds to produce hydrogen (H2) in an acidic solution (NixCd1-xS-Ni→2H+H2↑+Ni2++NixCd1-xS-Ni0). The equilibrium of photo-deposition/dissolution of Ni clusters realizes the construction of dynamic active sites, providing sustainable reaction centers and enhancing surface redox kinetics. The NixCd1-xS-Ni0 exhibits a high hydrogen evolution rate of 428 mmol·h-1·g-1 with a quantum efficiency of 75.6 % at 420 nm. This work provides the optimal S electronic structure for photocatalytic H2 evolution and constructs dynamic Ni clusters for chemical replacement reaction. This work provides the optimal S electronic structure for photocatalytic H2 evolution and constructs dynamic Ni clusters for displacement reaction, opening a dual pathway for efficient water reduction.

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