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1.
Proc Natl Acad Sci U S A ; 120(40): e2302851120, 2023 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-37748076

RESUMO

Sequentially managing the coverage and dimerization of *CO on the Cu catalysts is desirable for industrial-current-density CO2 reduction (CO2R) to C2+, which required the multiscale design of the surface atom/architecture. However, the oriented design is colossally difficult and even no longer valid due to unpredictable reconstruction. Here, we leverage the synchronous leaching of ligand molecules to manipulate the seeding-growth process during CO2R reconstruction and construct Cu arrays with favorable (100) facets. The gradient diffusion in the reconstructed array guarantees a higher *CO coverage, which can continuously supply the reactant to match its high-rate consumption for high partial current density for C2+. Sequentially, the lower energy barriers of *CO dimerization on the (100) facets contribute to the high selectivity of C2+. Profiting from this sequential *CO management, the reconstructed Cu array delivers an industrial-relevant FEC2+ of 86.1% and an FEC2H4 of 60.8% at 700 mA cm-2. Profoundly, the atomic-molecular scale delineation for the evolution of catalysts and reaction intermediates during CO2R can undoubtedly facilitate various electrocatalytic reactions.

2.
Small ; : e2402852, 2024 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-39118552

RESUMO

The seawater electrolysis to produce hydrogen is a significant topic on alleviating the energy crisis. Here, the Fe, Nb-Ni3S2 catalyst is prepared by metal-doping strategy, and it shows high oxygen evolution reaction (OER) activity in alkaline medium, and only needs 1.491 V to deliver a current density of 100 mA cm-2 in simulated seawater. Using Fe, Nb-Ni3S2 as a bifunctional catalyst, the two-electrode electrolyzer only requires a voltage of 1.751 V (without impedance compensation) to drive the current density of 50 mA cm-2, and can run over 150 h stably in the simulated seawater. Importantly, In situ Raman test demonstrates that the outstanding performance of Fe, Nb-Ni3S2 in simulated seawater is ascribed to the in situ formed sulfate protective layer induced by Nb doping, which can effectively inhibit the corrosion of chloride ion, while the protective layer is absent for Fe-Ni3S2. The stable operation of simulated seawater electrolysis under industrial current density further confirms the stability improvement mechanism of forming protective layer. In short, this study provides a new strategy of using Nb dopants inducing the formation of protective layer to enhance the stability of seawater electrolysis.

3.
Small ; 20(22): e2308517, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38155580

RESUMO

Metal organic frameworks (MOFs) are promising as effective electrocatalysts toward oxygen evolution reaction (OER). However, the origin of OER activity for MOF-based electrocatalysts is still unclear because of their structure reconstruction during electrocatalysis process. Here, a novel MOF (B-MOF-Zn-Co) with spherical superstructure is developed by hydrothermal treatment of zeolitic imidazolate framework-Zn, Co (ZIF-Zn-Co) using boric acid. The resultant B-MOF-Zn-Co shows high OER activity with a low overpotential of 362 mV at 100 mA cm-2. Remarkably, B-MOF-Zn-Co displays excellent stability with only 3.6% voltage delay over 300 h at 100 mA cm-2 in alkaline electrolyte. Surprisingly, B-MOF-Zn-Co thoroughly transforms into B-doped CoOOH (B-CoOOH) during electrolysis process, which is served as actual active material for high OER electrocatalytic performance. The newly-formed B-CoOOH possesses lower energy barrier of potential-determining step (PDS) for OOH* formation compared with CoOOH, benefiting for high OER activity. More importantly, B-MOF-Zn-Co based anion exchange membrane water electrolytic cell (AEMWE) demonstrates continuously durable operation with stable current density of 200 mA cm-2 over 300 h, illustrating its potential application in practice water electrolysis. This work offers an in situ electrochemical reconstruction strategy for the development of stable and effective OER electrocatalysts toward practice AEMWE.

4.
J Endovasc Ther ; : 15266028241253128, 2024 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-38733303

RESUMO

OBJECTIVE: The objective was to present our experience on managing mycotic infrarenal abdominal aortic aneurysm (MIAAA) through a retrospective cohort study. METHODS: Data of patients with MIAAA managed in our center from July 2016 to October 2022 were retrospectively analyzed. The diagnosis of MIAAA was made based on: (1) preoperative clinical signs of infection; (2) elevated serologic infection parameters; (3) para-aneurysmal infection features on enhanced computed tomography; and (4) positive blood or tissue cultures. All the patients received standard antibiotic therapy. Surgical management including endovascular aneurysm repair (EVAR), initial EVAR followed by open re-operation, and initial open surgical repair (OSR) were conducted according to disease seriosity, physical condition, and patient's will. Infection index and clinical outcome were evaluated during the follow-up time. RESULTS: A total of 23 patients (21 men; averaged=66.3 years, range=49-79 years) were included, with a mean follow-up time of 19.9 months (range=1-75 months). Bacteria culture from blood or tissue specimen was positive in 15 patients (Salmonella, n=8; Escherichia coli, n=3; methicillin-sensitive Staphylococcus aureus [MSSA], n=1; Klebsiella pneumoniae, n=1; Staphylococcus epidermidis, n=1; Mycobacterium tuberculosis, n=1). Seven patients received OSR as the initial surgical intervention, whereas 14 patients chose EVAR instead. The 2 conservatively managed patients (refused surgery) died within 30 days. The 7 patients who received initial OSR survived till now. Among the 14 patients who underwent initial EVAR, infection deteriorated without exception (14/14, 100%). Three of these patients refused re-operation and died within 6 months. Eleven patients received secondary surgical intervention (10 cases of aneurysm and endograft resection, thorough debridement, subclavian to bi-femoral artery bypass, or in situ aorta reconstruction; 1 case of laparoscopic debridement) and 7 survived the follow-up time. The overall mortality rate was 39.1% (9/23). The mortality rates differed greatly following different intervention methods (merely antibiotic management, 100%; initial open operation, 0%; initial EVAR without secondary operation, 100%; initial EVAR plus secondary operation, 36.4%). CONCLUSIONS: Open surgical repair is still the first choice for hemodynamically stable and low-risk patients. Merely EVAR is related with disastrous results, which should be reserved as a temporary alternative for patients with ruptured aneurysms, hemodynamic instability or high surgical risk, and followed by timely secondary OSR. CLINICAL IMPACT: The management of mycotic or primary-infected aortic aneurysm is challenging; treatment remains controversial. Our center has reviewed our experience over the past 6 years and found that open surgical repair is still the first choice for hemodynamically stable and low-risk patients. Merely endovascular aneurysm repair (EVAR) is related with disastrous results, which should be reserved as a temporary alternative for patients with ruptured aneurysms, hemodynamic instability or high surgical risk, and followed by timely secondary open surgical repair.

5.
Eur J Vasc Endovasc Surg ; 67(6): 997-1005, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38341175

RESUMO

OBJECTIVE: This study examines outcome and durability of physician made bovine pericardial tube grafts in aortic infections in all anatomical locations. METHODS: This was a retrospective and prospective international multicentre study. Peri-operative and long term outcomes of patients undergoing in situ aortic reconstruction for native or graft infections with physician made bovine pericardial tube grafts between January 2008 and December 2020 in four European tertiary referral centres were analysed. The primary endpoint was recurrent aortic infection. Secondary endpoints were persistent infection, aortic re-operation for infection, graft related complications, and death. RESULTS: One hundred and sixty eight patients (77% male, mean age 67 ± 11 years) were identified: 38 (23%) with native and 130 (77%) with aortic graft infection. The thirty day mortality rate was 15% (n = 26) overall, 11% (n = 4), and 17% (n = 22) for native and aortic graft infections, respectively (p = .45). Median follow up was 26 months (interquartile range [IQR] 10, 51). Estimated survival at one, two, three, and five years was 64%, 60%, 57%, and 50%, and significantly better for native (81%, 77%, 77%, and 69%) than for graft infections (58%, 55%, 51%, and 44%; p = .011). Nine patients (5.3%) had persistent infection and 10 patients (6%) had aortic re-infection after a median of 10 months (IQR 5, 22), resulting in an estimated freedom from re-infection at one, two, three, and five years of 94%, 92%, 90%, and 86%. Estimated freedom from graft complications at one, two, three, and five years was 91%, 89%, 87%, and 87%. CONCLUSION: This multicentre study demonstrates low re-infection rates when using physician made bovine pericardial tube grafts, comparable to those of other biological grafts. The rate of graft complications, mainly anastomotic aneurysms and stenoses, was low, while graft degeneration was absent. Physician made bovine pericardial tube grafts are an excellent tool for in situ reconstruction in the setting of native aortic infection or aortic graft infection.


Assuntos
Bioprótese , Implante de Prótese Vascular , Prótese Vascular , Pericárdio , Infecções Relacionadas à Prótese , Reoperação , Humanos , Masculino , Infecções Relacionadas à Prótese/cirurgia , Infecções Relacionadas à Prótese/mortalidade , Infecções Relacionadas à Prótese/microbiologia , Idoso , Feminino , Prótese Vascular/efeitos adversos , Bovinos , Pericárdio/transplante , Estudos Retrospectivos , Pessoa de Meia-Idade , Implante de Prótese Vascular/efeitos adversos , Implante de Prótese Vascular/instrumentação , Implante de Prótese Vascular/mortalidade , Europa (Continente) , Bioprótese/efeitos adversos , Reoperação/estatística & dados numéricos , Estudos Prospectivos , Animais , Resultado do Tratamento , Recidiva , Desenho de Prótese , Aorta/cirurgia , Fatores de Tempo
6.
Angew Chem Int Ed Engl ; 63(9): e202316640, 2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38146810

RESUMO

The catalyst-reconstruction makes it challenging to clarify the practical active sites and unveil the actual reaction mechanism during the CO2 electroreduction reaction (CO2 RR). However, currently the impact of the electrolyte microenvironment in which the electrolyte is in contact with the catalyst is overlooked and might induce a chemical evolution, thus confusing the reconstruction process and mechanism. In this work, the carbonate adsorption properties of metal oxides were investigated, and the mechanism of how the electrolyte carbonate affect the chemical evolution of catalysts were discussed. Notably, Bi2 O3 with weak carbonate adsorption underwent a chemical reconstruction to form the Bi2 O2 CO3 /Bi2 O3 heterostructure. Furthermore, in situ and ex situ characterizations unveiled the formation mechanism of the heterostructure. The in situ formed Bi2 O2 CO3 /Bi2 O3 heterostructure with strong electron interaction served as the highly active structure for CO2 RR, achieving a formate Faradaic efficiency of 98.1 % at -0.8 Vvs RHE . Theoretical calculations demonstrate that the significantly tuned p-orbit electrons of the Bi sites in Bi2 O2 CO3 /Bi2 O3 optimized the adsorption of the intermediate and lowered the energy barrier for the formation of *OCHO. This work elucidates the mechanism of electrolyte microenvironment for affecting catalyst reconstruction, which contributes to the understanding of reconstruction process and clarification of the actual catalytic structure.

7.
Ann Vasc Surg ; 78: 9-18, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34464724

RESUMO

INTRODUCTION: The best management of renal artery aneurysms (RAAs) remains controversial, especially when they are located from the mid to distal portions of the main renal artery. Our aim is to evaluate our 10-year experience with in situ open surgical repairs from a cohort of non-proximal RAAs at a single vascular surgery center. METHODS: A retrospective review of a prospectively maintained database of all patients who underwent RAA in situ repairs located from the mid to distal portions of the renal artery at our Institution was performed between 2009 and 2020. Data on patient demographics, comorbidities, aneurysm location and morphology, type of in situ technique, and perioperative data were assessed. Postoperative biomarkers and renal function were collected, and mid-term follow-up results were analyzed. RESULTS: A total of 15 RAA located at mid and distal portions of the renal artery repaired with in situ techniques were performed in 15 patients (nine men, mean age 62.4 ± 6.36 years). At diagnosis, 12 patients were asymptomatic; a history of abdominal pain was found in one patient, and two patients had drug-resistant hypertension. Two patients had already undergone previous unsuccessful attempts of endovascular treatment. All patients presented an aneurysm diameter >20 mm (mean diameter 2.75 ± 5 mm). At admission, mean serum creatinine and glomerular filtration rate were 1.10 ± 0.23 mg/dL and 69.8 ± 9.8 mL/min/1.73 m2, respectively. Nine lesions were present in the distal portion of the renal artery, with 4 cases having ≥3 efferent branches and the other 5 with two efferent branches. The other six RAAs were in the mid-portion: in 4 cases, one efferent branch, and in 2 cases, two efferent branches were involved. All patients underwent in situ open repair: an end-to-end anastomosis was performed in 9 cases, aneurysm resection with primary closure in 3 cases, bypass with graft interposition in 2 cases (one iliac-renal reconstruction), and with vein interposition in 1 case. The mean renal ischemia time was 21.8 ± 9.4 min. A significant decrease on renal function was not observed (mean glomerular filtration rate at discharge: 64.8 ± 12.0 mL/min/1.73m2; P > 0.22). During recovery, one patient developed retroperitoneal hematoma treated conservatively. During follow-up (mean 46 months, range 2-135), one patient developed occlusion of a terminal renal artery branch without decreased kidney function. CONCLUSION: In situ techniques for RAA from the mid to distal portions of the renal artery are technically complex; however, based on our results, these procedures were safe and effective, providing satisfactory early and mid-term outcomes.


Assuntos
Aneurisma/cirurgia , Artéria Renal/cirurgia , Procedimentos Cirúrgicos Vasculares/métodos , Idoso , Anastomose Cirúrgica , Aneurisma/complicações , Aneurisma/diagnóstico por imagem , Creatinina/sangue , Feminino , Taxa de Filtração Glomerular , Humanos , Hipertensão/complicações , Rim/irrigação sanguínea , Rim/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Artéria Renal/diagnóstico por imagem , Estudos Retrospectivos , Taxa de Sobrevida , Resultado do Tratamento
8.
Ann Vasc Surg ; 82: 206-211, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-34902469

RESUMO

BACKGROUND: The empiric antibiotic regimen started after deep cultures and explantation of the graft mostly do not cover antifungals. We retrospectively studied the outcome of candida compared to non-candida VGI and assessed whether these results could justify the addition of antifungals to the empiric antibiotics in the early postoperative period. METHODS: All patients treated for infected aorto(ilio)femoral graft with excision and reconstruction at the vascular department of University Hospitals Leuven between January 2010 and 2017 (n = 56) were studied retrospectively. Patients were allocated to the candida group (n = 10) or non-candida group (n = 46) according to the presence of Candida in deep culture isolates. RESULTS: All-cause mortality was significantly higher in the candida group compared to the non-candida group. All-cause 30-day mortality was 40% and 13% for both groups respectively (P = 0.066). At 5 years this was 90% and 46% respectively (P = 0.014). In the candida group 6 patients (60%) had to be revised in the operating room due to bleeding, compared to 5 patients (11%) in the non-candida group (P = 0.002).  Two patients (20%) and 5 patients (11%) had to be readmitted to the ICU, respectively. CONCLUSION: Survival of candida related VGI is significantly worse, especially in the first 5 postoperative months. This could justify the addition of an antifungal to the early empiric postoperative antibiotic cocktail, especially in patients with an aorto-enteric fistula. A cost-benefit analysis could be useful to evaluate the yield.


Assuntos
Infecções Relacionadas à Prótese , Doenças Vasculares , Antibacterianos/efeitos adversos , Antifúngicos/uso terapêutico , Prótese Vascular/efeitos adversos , Candida , Humanos , Infecções Relacionadas à Prótese/diagnóstico , Infecções Relacionadas à Prótese/microbiologia , Infecções Relacionadas à Prótese/cirurgia , Estudos Retrospectivos , Resultado do Tratamento , Doenças Vasculares/etiologia
9.
Small ; 16(23): e1907556, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32378323

RESUMO

Carbides are commonly regarded as efficient hydrogen evolution reaction (HER) catalysts, but their poor oxygen evolution reaction (OER) catalytic activities seriously limit their practical application in overall water splitting. Here, vertically aligned porous cobalt tungsten carbide nanosheet embedded in N-doped carbon matrix (Co6 W6 C@NC) is successfully constructed on flexible carbon cloth (CC) as an efficient bifunctional electrocatalyst for overall water splitting via a facile metal-organic framework (MOF) derived method. The synergistic effect of Co and W atoms effectively tailors the electron state of carbide, optimizing the hydrogen-binding energy. Thus Co6 W6 C@NC shows an enhanced HER performance with an overpotential of 59 mV at a current density of -10 mA cm-2 . Besides, Co6 W6 C@NC easily in situ transforms into tungsten actived cobalt oxide/hydroxide during the OER process, serving as OER active species, which provides an excellent OER activity with an overpotential of 286 mV at a current density of -10 mA cm-2 . The water splitting device, by applying Co6 W6 C@NC as both the cathode and anode, requires a low cell voltage of 1.585 V at 10 mA cm-2 with the great stability in alkaline solution. This work provides a feasible strategy to fabricate bimetallic carbides and explores their possibility as bifunctional catalysts toward overall water splitting.

10.
J Endovasc Ther ; 24(5): 688-697, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28756719

RESUMO

PURPOSE: To report a meta-analysis of the published evidence on the outcomes of aortic endograft infection after endovascular aneurysm repair (EVAR). METHODS: A search of electronic information sources (PubMed/MEDLINE, SCOPUS, CENTRAL) and bibliographic reference lists identified 12 studies reporting on 362 patients (mean age 72 years; 279 men). The methodological quality of the selected studies was assessed using the Newcastle-Ottawa scale. Endpoints were 30-day/in-hospital mortality and follow-up mortality. Pooled estimates are reported with the 95% confidence interval (CI). The review was registered at the International Prospective Register of Systematic Reviews in Health and Social Care (CRD42016034166). RESULTS: The incidence of graft infection after EVAR was 0.6% (95% CI 0.4% to 0.8%). The time from implantation to diagnosis ranged from 1 to 128 months (mean 25). The majority of patients (293, 81%) underwent surgical treatment (95% CI 77% to 83%); 9 (2.5%) patients (95% CI 21% to 43%) received conservative treatment. Aortic replacement with a prosthetic graft was performed in 58% (95% CI 52% to 62%), whereas cryopreserved allografts and autologous grafts were used in 31% (95% CI 28% to 33%) and 11% (95% CI% 8 to 14%), respectively. Less than half of the patients (40%) had emergency surgery. The pooled estimate of 30-day/in-hospital mortality was 26.6% (95% CI 16.9% to 39.2%). The pooled 30-day/in-hospital mortality for 9 patients treated conservatively was 63.3% (95% CI 30.7% to 87.0%). The pooled overall follow-up mortality was 45.7% (95% CI 36.4% to 55.4%) vs 58.6% (95% CI 28.8% to 83.3%) for the 9 patients receiving conservative treatment. CONCLUSION: Aortic endograft infection is a rare complication after EVAR. Surgical treatment with complete explantation of the infected endograft seems to be the optimal management in selected patients. Supportive medical treatment without surgical intervention has a significant associated mortality.


Assuntos
Aneurisma da Aorta Abdominal/cirurgia , Implante de Prótese Vascular/efeitos adversos , Implante de Prótese Vascular/instrumentação , Prótese Vascular/efeitos adversos , Procedimentos Endovasculares/efeitos adversos , Procedimentos Endovasculares/instrumentação , Infecções Relacionadas à Prótese/microbiologia , Stents/efeitos adversos , Adulto , Idoso , Idoso de 80 Anos ou mais , Antibacterianos , Aneurisma da Aorta Abdominal/mortalidade , Implante de Prótese Vascular/mortalidade , Tratamento Conservador , Remoção de Dispositivo , Procedimentos Endovasculares/mortalidade , Feminino , Mortalidade Hospitalar , Humanos , Masculino , Pessoa de Meia-Idade , Infecções Relacionadas à Prótese/diagnóstico , Infecções Relacionadas à Prótese/mortalidade , Infecções Relacionadas à Prótese/terapia , Medição de Risco , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento
11.
J Colloid Interface Sci ; 674: 1048-1057, 2024 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-39003820

RESUMO

Understanding and utilizing the dynamic changes of electrocatalysts under working conditions are important for advancing the sustainable hydrogen production. Here, we for the first time report that Cr-doping can promote the in situ reconstruction of a self-supported Ni3N electrocatalyst (Cr-Ni3N/NF) during oxygen and hydrogen evolution reactions (OER and HER), and therefore improve the electrocatalytic water splitting performance. As identified by in situ measurements and theoretical calculations, Cr-doping enhances OH- adsorption during OER at anode and thereby boosts the transformation of Ni3N pre-catalysts to defect-rich nickel oxyhydroxide (NiOOH) active species. Meanwhile, it facilitates the generation of Ni3N/Ni(OH)2 at cathodes due to effective H2O activation, leading to the fast HER kinetics on the Ni3N/Ni(OH)2 interfaces. Notably, the optimal Cr-Ni3N/NF displays good OER and HER performance in 1.0 M KOH electrolytes, with low overpotentials of 316 and 188 mV to achieve the current density of ± 100 mA cm-2, respectively. Benefiting from its bi-functionality and self-supporting property, an alkaline electrolyzer equipped with Cr-Ni3N/NF as both anode and cathode affords a small voltage of 1.72 V at 100 mA cm-2, along with 100 h operation stability. Elucidating that Cr-doping can boost in situ reconfiguration and consequently the electrocatalytic activity, this work would shed new light on the rational design and synthesis of electrocatalysts via directional reconstructions.

12.
ACS Appl Mater Interfaces ; 16(1): 742-751, 2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-38110327

RESUMO

Electrochemical CO2 reduction reaction (eCO2RR) is a viable approach to achieve carbon neutrality. Bismuth-based electrocatalysts demonstrate exceptional selectivity in CO2-to-formate conversion, but their reconstruction mechanisms during the eCO2RR remain elusive. Herein, the reconstruction processes of bismuth molybdate (Bi2MoO6) nanoplates are elucidated during the eCO2RR. Operando and ex situ measurements reveal the in situ partial reduction of Bi2MoO6 to Bi metal, forming Bi@Bi2MoO6 at negative potentials. Meanwhile, CO32- ions in the electrolyte spontaneously exchange with MoO42- in Bi2MoO6. The obtained Bi@Bi2MoO6/Bi2O2CO3 delivers a formate Faradaic efficiency (FE) of 95.2% at -1.0 V. Notably, high formate FEs (>90%) are maintained within a wide 500 mV window. Although computational calculations indicate a higher energy barrier for *OCHO formation on Bi2O2CO3, the prevention of excessive reduction to metal Bi significantly enhances long-term stability. Furthermore, the CO32- ion exchange process occurs in various 2D Bi-containing precatalysts, which should be emphasized in further studies.

13.
ACS Appl Mater Interfaces ; 16(30): 39305-39311, 2024 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-39036881

RESUMO

Renewable energy-driven electrocatalytic CO2 reduction reaction (CO2RR) over bismuth-based catalysts shows great promise for converting CO2 into formic acid and formate while closing the carbon cycle. Herein, we report a high-performance BiFeO3/Bi25FeO40 precatalyst, which delivers a formate partial current density of 359.8 mA cm-2 and a formate formation rate of 6.71 mmol h-1 cm-2 in a flow cell at -0.75 V versus reversible hydrogen electrode (vs RHE). Furthermore, it shows stable formate production for 88 h at -0.64 V vs RHE with a total current density of 160 mA cm-2. The impressive electrocatalytic performance toward CO2RR to formate is likely ascribed to the synergistic effect of single Bi atoms and bimetallic BiFe nanoparticles present in close proximity after in situ electrochemical reconstruction of the BiFeO3/Bi25FeO40 precatalyst. This work presents new insights into the development of highly efficient Bi-based catalysts for the CO2RR.

14.
ACS Appl Mater Interfaces ; 15(5): 7529-7537, 2023 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-36694419

RESUMO

The electrochemical carbon dioxide reduction reaction (CO2RR) catalyzed by Sn-based materials shows great potential for CO2-to-formate conversion. The presence of tin species with different oxidation states can promote the catalytic performance, most likely due to the interfaces of metallic and oxide phases that induce a synergistic effect. Therefore, it is desirable yet challenging to synthesize a hybrid catalyst with abundant active heterogeneous interfaces. Herein, we synthesize a hybrid catalyst constructed by decorating nanosized SnS2 in the SnO2 matrix. The uniformly distributed SnS2 nanoparticles are first reduced to metallic tin, which assists in the generation of abundant Sn/SnO2 heterogeneous interfaces under the in situ reduction process. Because of the electronic modulation at the heterogeneous interfaces, the resulting catalyst delivers a high current density of 200 mA·cm-2 at -0.86 V vs RHE, and the performance is stable for over 20 h. This work suggests a potentially powerful interface engineering strategy for the development of high-performance electrocatalysts for the CO2RR.

15.
J Colloid Interface Sci ; 652(Pt B): 1347-1355, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-37666189

RESUMO

Noble metal free electrocatalysts for hydrogen evolution reaction (HER) in acid play an important role in proton exchange membrane-based electrolysis. Here, we develop an in situ surface self-reconstruction strategy to construct excellent acidic HER catalysts. Firstly, free-standing zinc nickel tungstate nanosheets inlaid with nickel tungsten alloy nanoparticles were synthesized on carbon cloth as pre-catalyst via metal-organic framework derived method. Amorphous nickel tungsten oxide (Ni-W-O) layer is in situ formed on surface of nanosheet as actual HER active site with the dissolution of NiW alloy nanoparticles and the leaching of cations. While the morphology of the free-standing structure remains the same, keeping the maximized exposure of active sites and serving as the electron transportation framework. As a result, benefiting from disordered arrangement of atoms and the synergistic effect between Ni and W atoms, the amorphous Ni-W-O layer exhibits an excellent acidic HER activity with only an overpotential of 46 mV to drive a current density of 10 mA cm-2 and a quite good Tafel slope of 36.4 mV dec-1 as well as an excellent durability. This work enlightens the exploration of surface evolution of catalysts during HER in acidic solution and employs it as a strategy for designing acidic HER catalysts.

16.
Artigo em Inglês | MEDLINE | ID: mdl-37364018

RESUMO

Infectious aortic disease is a challenging life-threatening disease in cardiovascular surgery. A 70-year-old man patient presented with an infected infrarenal aortic pseudoaneurysm and right iliac artery- left iliac vein fistula (arteriovenous fistula). He underwent total infected tissues excision, debridement, in situ reconstructions of the aorta using a self-made pericardium graft with omental coverage and arteriovenous fistula patch repair to prevent leakage. One-year follow-up revealed the absence of clinically relevant infection with patency of the graft and the absence of biochemical inflammatory markers.

17.
Front Chem ; 10: 1104844, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36688037

RESUMO

Cobalt (Co) as a substitute of noble-metal catalysts shows high catalytic capability for production of the widely used primary amines through the reductive amination. However, the synthesis of Co catalysts usually involves the introduction of organic compounds and the high-temperature pyrolysis, which is complicated and difficult for large-scale applications. Herein, we demonstrated a facile and efficient strategy for the preparation of Co catalysts through the in situ reconstruction of cobalt borate (CoBOx) during the reductive amination, delivering a high catalytic activity for production of benzylamine from benzaldehyde and ammonia. Initially, CoBOx was transformed into Co(OH)2 through the interaction with ammonia and subsequently reduced to Co nanoparticles by H2 under the reaction environments. The in situ generated Co catalysts exhibited a satisfactory activity and selectivity to the target product, which overmatched the commonly used Co/C, Pt or Raney Ni catalysts. We anticipate that such an in situ reconstruction of CoBOx by reactants during the reaction could provide a new approach for the design and optimization of catalysts to produce primary amines.

18.
Diagnostics (Basel) ; 12(11)2022 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-36428890

RESUMO

BACKGROUND: The aim of this study was to evaluate the effectiveness of positron emission tomography/computed tomography with [18F]-fludeoxyglucose (FDG-PET/CT) and radiomics analysis in detecting differences between the native aorta and the abdominal aortic allograft after the total eradication of infection in patients undergoing infected graft removal and in situ reconstruction with cryopreserved allografts. METHODS: Between January 2008 and December 2018, 56 vascular reconstructions with allografts have been performed at our department. The present series included 12 patients undergoing abdominal aortic in situ reconstruction with cryopreserved allografts. During the follow-up, all patients underwent a total-body [18F]FDG PET/CT with subsequent radiomics analysis. In all patients, a comparative analysis between the data extracted from native aorta and cryopreserved graft for each patient was performed. RESULTS: All patients were male with a mean age of 72.8 years (range 63-84). Mean duration of follow-up was 51.3 months (range 3-120). During the follow-up, 2 patients (16.7%) needed a redo allograft-related surgical intervention. Overall, the rate of allograft dilatation was 33.3%. No patient had a redo infection during the follow-up. Radiomics analysis showed a different signature of implanted allograft and native aorta. Comparative analysis between the native aortas and cryopreserved allografts (dilated or not) showed several statistical differences for many texture features. CONCLUSIONS: The higher metabolic activity of allografts could indicate a state of immune-mediated degeneration. This theory should be proven with prospective, multicentric studies with larger sample sizes.

19.
J Clin Med ; 11(21)2022 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-36362816

RESUMO

BACKGROUND: This study aimed to evaluate the outcome of various treatment options for aortic graft infection (AGI) patients and identify factors affecting their prognosis. METHODS: The data of AGI patients from January 2008 to December 2019 were retrospectively collected and analyzed. The primary endpoints were 30-day mortality and perioperative complication-related morbidity; the secondary endpoints were re-infection (RI) rates, primary and secondary graft patency, overall mortality, duration of antibiotic therapy, and the number of antibiotic types used in treatment. RESULTS: There was no significant difference in the 30-day mortality and perioperative-related complications between the conservative treatment, in-situ reconstruction (ISR), and extra-anatomic reconstruction (EAR) groups. The ISR group had lower re-infection rates and better overall survival rates than the EAR and conservative treatment groups. Different bypass graft conduits had no significant influence on the RI rate or primary and secondary graft patency. AGI patients infected with high-virulence pathogens had higher RI and overall mortality rates than those infected with low virulence pathogens, but this was not statistically significant. Initial procedures prior to the AGI also had no influence on the prognosis of AGI patients. Patients undergoing ISR or EAR surgery received antibiotic therapy for a longer duration than patients undergoing conservative treatment. Patients without RI received more types of antibiotics than patients with RI. CONCLUSIONS: ISR had lower RI rates and better overall survival rates than EAR and conservative treatment and may be a better choice for patients with AGI. Several factors were found to have no influence on patients' prognosis however, further studies are required.

20.
J Colloid Interface Sci ; 622: 728-737, 2022 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-35537224

RESUMO

Bi-functional electrocatalysts are desired for both hydrogen and oxygen evolution reactions (HER and OER). Herein, facile O2-plasma activation is introduced to improve the bi-functionality via constructing nickel sulfide-oxide heterostructures. Ni3S2-NiOx supported by nickel foam delivers obviously elevated HER and OER activity in comparison with pristine Ni3S2 and recently reported NiSx-based electrocatalysts, featured by the low overpotentials for HER (104 mV) and OER (241 mV) at ±10 mA cm-2 in 1.0 M KOH, as well as a voltage of 1.52 V for overall water splitting. As revealed by in-situ Raman spectroscopy, on the one hand, Ni(OH)2 generated from Ni3S2 during alkaline HER accelerates water dissociation toward the gradually improved performance; on the other hand, this heterostructure undergoes extensive oxidation during OER, leading to excessive NiOOH covering on Ni3S2 and thereby declining activity. These changes are interpreted by the distinct thermodynamic relationship under specific electrochemical conditions via density functional theory calculations.

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