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1.
Materials (Basel) ; 16(15)2023 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-37570134

RESUMO

Ni/CaO, a low-cost dual-functional material (DFM), has been widely studied for integrated CO2 capture and hydrogenation. The core of this dual-functional material should possess both good CO2 capture-conversion performance and structural stability. Here, we synthesized Ni/CaO DFMs modified with alkali metals (Na, K, and Li) through a combination of precipitation and combustion methods. It was found that Na-modified Ni/CaO (Na-Ni/CaO) DFM offered stable CO2 capture-conversion activity over 20 cycles, with a high CO2 capture capacity of 10.8 mmol/g and a high CO2 conversion rate of 60.5% at the same temperature of 650 °C. The enhanced CO2 capture capacity was attributed to the improved surface basicity of Na-Ni/CaO. In addition, the incorporation of Na into DFMs had a favorable effect on the formation of double salts, which shorten the CO2 capture and release process and promoted DFM stability by hindering their aggregation and the sintering of DFMs.

2.
ACS Omega ; 7(13): 11217-11225, 2022 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-35415345

RESUMO

Highly dispersed Pt nanoparticles (∼2.5 nm) on phosphorus-doped activated coconut shell carbon (Pt/P-ACC) were synthesized by a two-step impregnation route. Pt/P-ACC showed a high activity, chemoselectivity, and reusability toward the hydrogenation of nitrobenzene to p-aminophenol, with hydrogen as the reducing agent in sulfuric acid. The effects of P species on the catalyst structure, surface properties, and catalytic performance were investigated. It was found that the Pt/P-ACC catalyst had an excellent catalytic activity due to its smaller Pt nanoparticles and higher content of surface-active metal compared with Pt/ACC. Besides, the experimental results and in situ infrared studies demonstrated that the interaction effect between the Pt and P species imbued the surface of Pt with an electron-rich feature, which decreased the adsorption of electron-rich substrates (that is, phenylhydroxylamine) and prevented their full hydrogenation, leading to enhanced selectivity during the hydrogenation of nitrobenzene to p-aminophenol.

3.
Materials (Basel) ; 14(20)2021 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-34683532

RESUMO

A series of Al-P-O catalysts (Al-xP-O) were prepared using a P123-assisted one-pot method at different P/Al molar ratios and used for O-methylation of catechol and methanol. The influences of the P/Al molar ratio and P123 addition on catalyst structure and surface acid-base characteristics were investigated in detail. Increasing the P/Al molar ratio more favored crystalline aluminophosphate. The P123-assisted Al3+ and PO43- are known to be stabilized through weak steric force so that the formation of crystalline aluminophosphate could be inhibited at higher P/Al molar ratios. The results showed that the prepared Al-P-O catalysts possessed appropriate weak acid and weak base sites, which was beneficial to the reaction of catechol and methanol. The Al-1.1P-O catalyst synthesized with the assistance of P123 exhibited superior catalytic performances, with 52.5% catechol conversion and higher guaiacol selectivity of 97.6%.

4.
Chem Commun (Camb) ; 57(37): 4576-4579, 2021 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-33956000

RESUMO

Green oxidation of 2,2'-hydrazobis-isobutyronitrile (HAIBN) to 2,2'-azobis-isobutyronitrile (AIBN) over a recyclable solid catalyst was a significant challenge. A titanium dioxide-supported chromium oxide (CrOx/TiO2) catalyst was, for the first time, developed for oxidation of HAIBN with hydrogen peroxide and achieved complete conversion of HAIBN with a high (94.8%) yield of AIBN.

5.
PeerJ ; 8: e8638, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32117642

RESUMO

OBJECTIVE: Endoplasmic reticulum (ER) stress is involved in the pathogenesis of various ophthalmic diseases, and ER stress-mediated degradation systems play an important role in maintaining ER homeostasis during ER stress. The purpose of this review is to explore the potential relationship between them and to find their equilibrium sites. DESIGN: This review illustrates the important role of reasonable regulation of the protein degradation system in ER stress-mediated ophthalmic diseases. There were 128 articles chosen for review in this study, and the keywords used for article research are ER stress, autophagy, UPS, ophthalmic disease, and ocular. DATA SOURCES: The data are from Web of Science, PubMed, with no language restrictions from inception until 2019 Jul. RESULTS: The ubiquitin proteasome system (UPS) and autophagy are important degradation systems in ER stress. They can restore ER homeostasis, but if ER stress cannot be relieved in time, cell death may occur. However, they are not independent of each other, and the relationship between them is complementary. Therefore, we propose that ER stability can be achieved by adjusting the balance between them. CONCLUSION: The degradation system of ER stress, UPS and autophagy are interrelated. Because an imbalance between the UPS and autophagy can cause cell death, regulating that balance may suppress ER stress and protect cells against pathological stress damage.

6.
Orthop Surg ; 11(1): 42-51, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30714333

RESUMO

OBJECTIVE: To investigate the indications, surgical strategy and techniques, safety, and efficacy of robot-assisted minimally-invasive internal fixation of pelvic ring injuries. METHODS: The clinical data of 86 patients with anterior and posterior pelvic ring injuries who underwent robot-assisted minimally-invasive internal fixation were retrospectively analyzed. The patients included 57 men and 29 women aged between 22 and 75 years, with an average age of (40.2 ± 13.6) years. According to the Tile classification, there were 5 (5.8%) type A2, 48 (55.8%) type B, and 33 (38.4%) type C fractures. The surgical plans were formulated based on the injury type of the pelvic ring, the effectiveness of the reduction, and the integrity of the osseous channel. Posterior pelvic ring injuries were treated with robot-assisted percutaneous cannulated screw fixation of the sacroiliac joint. Anterior pelvic ring injuries were treated with robot-assisted percutaneous cannulated screw fixation of the pubic ramus, INFIX fixation, or a "hybrid" fixation. The surgical complications and the efficacy of the surgical treatments were analyzed. RESULTS: A total of 274 screws were inserted with robotic assistance, of which 262 screws were successfully inserted to a satisfactory position on the first attempt. The number of screws placed per person was 3.2 on average, and the average operation time was 175 min (35-280 min). Fluoroscopies were performed an average of 29.1 times (range, 9-63 times), and it took 6.1 s to place each screw. There were 13 unsatisfactory guiding needle placements during the surgeries, among 7 of which cutting or penetration of the cortex was re-planned until satisfactory insertions; 1 penetrated the pubic cortex, causing hemorrhage of the "crown of death," and was changed to "hybrid surgery". The robot-assisted surgical wounds all healed by primary intention with satisfactory position and precision of screw insertions. All patients were followed up for 3-6 months, with an average of 4.2 months. There were two postoperative fixation failures, in which both patients had separated symphysis pubes after hybrid surgery. The average Majeed score at the last follow-up was 92.4 points. CONCLUSIONS: Robot-assisted surgery is accurate and minimally invasive, with a high success rate for one-time screw placement and satisfactory clinical results. The indications and surgical strategy should be rigorously selected, the level of surgical techniques mastered, and the operating procedures standardized, all of which may help to prevent surgical complications. Robot-assisted surgery provides a novel modality for the minimally-invasive treatment of pelvic ring injuries.


Assuntos
Fixação Interna de Fraturas/métodos , Fraturas Ósseas/cirurgia , Ossos Pélvicos/lesões , Procedimentos Cirúrgicos Robóticos/métodos , Adulto , Idoso , Parafusos Ósseos , Feminino , Fixação Interna de Fraturas/efeitos adversos , Fixação Interna de Fraturas/instrumentação , Consolidação da Fratura , Fraturas Ósseas/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Procedimentos Cirúrgicos Minimamente Invasivos/efeitos adversos , Procedimentos Cirúrgicos Minimamente Invasivos/instrumentação , Procedimentos Cirúrgicos Minimamente Invasivos/métodos , Ossos Pélvicos/diagnóstico por imagem , Ossos Pélvicos/cirurgia , Complicações Pós-Operatórias , Radiografia , Estudos Retrospectivos , Procedimentos Cirúrgicos Robóticos/efeitos adversos , Procedimentos Cirúrgicos Robóticos/instrumentação , Resultado do Tratamento , Adulto Jovem
7.
ACS Appl Mater Interfaces ; 10(6): 5413-5428, 2018 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-29368913

RESUMO

Mesoporous γ-alumina (γ-MA)-supported cobalt oxides (Co3O4) with large surface areas and narrow pore size distributions were first prepared through one-pot hydrolysis of metal nitrates. The obtained Co3O4/γ-MA materials were impregnated with a water-ethanol solution of 1,10-phenanthroline, followed by treatment at 700 °C in N2 atmosphere, generating Co-NC/γ-MA catalysts containing N-doped graphitic carbon (NC). The Co-NC/γ-MA catalysts maintained the mesoporous structure of γ-MA, and Co3O4 was reduced to metallic Co nanoparticles highly dispersed in the γ-MA frameworks. Metallic Co species had a strong interaction with NC in the matrices, avoiding the surface oxidation of Co particles. The Co-NC/γ-MA catalysts exhibited superior catalytic activity and quantitatively reduced a variety of functionalized nitroarenes to the corresponding arylamines with hydrazine hydrate in ethanol at near room temperature, affording yields of >99%. The recycling test of 2-chloronitrobenzene as a model reaction showed no detectable change in catalyst performance after 10 cycle reactions.

8.
RSC Adv ; 8(16): 8898-8909, 2018 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-35539833

RESUMO

Herein, nanoscale metallic nanoparticle-incorporated ordered mesoporous carbon catalysts activated by nitrogen-doped graphene (NGr) were fabricated via an efficient multi-component co-assembly of a phenolic resin, nitrate, acetylacetone, the nitrogen-containing compound 1,10-phenanthroline, and Pluronic F127, followed by carbonization. The obtained well-dispersed nitrogen-doped graphene-activated transition metal nanocatalysts possess a 2-D hexagonally arranged pore structure with a high surface area (∼500 m2 g-1) and uniform pore size (∼4.0 nm) and show excellent activity for the selective hydrogenation-reduction of substituted nitroarenes to anilines in an environmentally friendly aqueous solution. The high catalytic performance and durability is attributed to the synergistic effects among the components, the unique structure of the nitrogen-doped graphene layer-coated metallic nanoparticles, and electronic activation of the doped nitrogen.

9.
Chempluschem ; 81(9): 908-912, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31968807

RESUMO

Direct synthesis of metal/carbon nanocomposites with ordered mesoporous frameworks has attracted increasing interest in various applications including catalysis, optics, and electronics. Herein, we demonstrate a simple one-pot co-assembly route to synthesize Ru/carbon composites by using resol, ruthenium chloride, and Pluronic F127 as a template with the assistance of 8-hydroxyquinoline. 8-Hydroxyquinoline exerts a significant influence on the mesostructure ordering and specific surface area of the Ru/carbon composites. The obtained Ru/carbon materials show well-ordered hexagonal arrays of mesopores with homogeneously dispersed sub-2 nm Ru nanoclusters throughout the carbon frameworks, which can efficiently and quantitatively hydrogenated nitrobenzene to aniline with H2 in the absence of solvent for multiple recycling runs without loss of activity.

10.
ScientificWorldJournal ; 2014: 414717, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25006592

RESUMO

Discovering critical nodes in social networks has many important applications. For finding out the critical nodes and considering the widespread community structure in social networks, we obtain each node's marginal contribution by Owen value. And then we can give a method for the solution of the critical node problem. We validate the feasibility and effectiveness of our method on two synthetic datasets and six real datasets. At the same time, the result obtained by using our method to analyze the terrorist network is in line with the actual situation.


Assuntos
Algoritmos , Modelos Teóricos , Rede Social
11.
Chem Commun (Camb) ; (37): 4442-4, 2008 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-18802584

RESUMO

Stable Au nanoparticles in P123 aqueous solution using a simple method have been developed and the colloidal Au nanoparticles were successfully applied for the effective oxidation of various alcohols using molecular O2 as oxidant at 30 degrees C in aqueous solution.

12.
J Phys Chem B ; 109(5): 1763-9, 2005 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-16851156

RESUMO

SBA-15 mesoporous silica has been functionalized with aminopropyl groups through a simple co-condensation approach of tetraethyl orthosilicate (TEOS) and (3-aminopropyl)triethoxysilane (APTES) using amphiphilic block copolymers under acidic conditions. The organic-modified SBA-15 materials have hexagonal crystallographic order, pore diameter up to 60 A, and the content of aminopropyl groups up to 2.3 mmol g(-1). The influences of TEOS prehydrolysis period and APTES concentration on the crystallographic order, pore size, surface area, and pore volume were examined. TEOS prehydrolysis prior to the addition of APTES was found essential to obtain well-ordered mesoporous materials with amino functionality. The amount of APTES incorporated in the silica framework increased with the APTES concentration in the synthesis gel, while the ordering of the mesoporous structure gradually decreased. Analysis with TG, IR, and solid state NMR spectra demonstrated that the aminopropyl groups incorporated in SBA-15 were not decomposed during the preparation procedure and the surfactant P123 was fully removed through ethanol extraction. The modified SBA-15 was an excellent base catalyst in Knoevenagel and Michael addition reactions.

13.
Chem Commun (Camb) ; (23): 2762-3, 2004 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-15568105

RESUMO

Highly ordered large pore SBA-15 silica functionalized with up to 16% aminopropyl groups, which gave high catalytic activity and selectivity toward flavanone synthesis through aldol condensation and subsequent intramolecular Michael addition of benzaldehyde and 2'-hydroxyacetophenone, was synthesized for the first time via co-condensation of tetraethylorthosilicate (TEOS) and 3-aminopropyltriethoxysilane (APTES) using an amphiphilic block copolymer as the structure-directing agent.

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