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1.
ACS Appl Mater Interfaces ; 15(8): 10761-10773, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36786765

RESUMO

Hydrogenation of naphthalene can effectively reduce the content of aromatics in oil and generate high-value products. A series of Pt-based aluminum-modified core-shell-structured hierarchically periodic mesoporous organosilica@mesoporous silica nanoparticles (Pt/Al-x-PMOs@MSNs) were successfully synthesized and tested for the hydrogenation properties, with preferable mass transfer of macromolecular reactants in the pores and increasing the total acidity of the catalysts. Moreover, the physicochemical properties of the core-shell-structured Pt-based catalysts were systematically analyzed using various characterization techniques. At 300 °C, the naphthalene conversion on the Pt/Al-10-PMOs@MSNs catalyst reached up to 100%, the selectivity of trans-decalin reached 83.9%, and the rate constants (k1, k2) and TOF were 13.2 × 10-6 mol·g-1·s-1, 1.7 × 10-7 mol·g-1·s-1, and 218.8 h-1, respectively. In the presence of sulfur, the naphthalene hydrogenation over the Pt/Al-10-PMOs@MSN catalyst first decreased to around 40% and then recovered to the original level, which originated from the synergistic effect of the texture and chemical properties over the Pt/Al-10-PMOs@MSNs with an excellent performance.

2.
J Eukaryot Microbiol ; 70(3): e12960, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36478629

RESUMO

Blastocystis sp. is one of the most common intestinal parasites in humans and many animals. To further understand the infection of Blastocystis hominis (B. hominis) and the distribution of its genotype in some areas of Henan Province, China, 793 stool samples from outpatients and inpatients in Xinxiang City and Xinyang City, Henan Province were collected from April 2020 to July 2022. The samples were detected by polymerase chain reaction and analyzed by univariate analysis and logistic regression analysis. The results showed that the infection rates of B. hominis in Xinxiang and Xinyang were 10.97% (51/465) and 10.98% (36/328), respectively. Although there were no significant differences in B. hominis infection between gender, age, residence, and disease background, the incidence of hematochezia significantly differed from the incidence of abdominal pain, diarrhea, and constipation among participants (χ2  = 15.795, p = 0.002). A total of 87 positive samples were sequenced and compared with Basic Local Alignment Search Tool, and five subtypes (ST1, ST3, ST4, ST6, and ST7) were identified, of which ST3 was the dominant subtype (63.22%, 55/87), followed by ST7 (17.24%, 15/87) and ST1 (16.09%, 14/87). This is the first study that analyzed the prevalence and subtype distribution of B. hominis in southern and northern Henan Province, thus providing new insights into the epidemiology of B. hominis.


Assuntos
Blastocystis , Animais , Humanos , Blastocystis/genética , Prevalência , Pacientes Internados , Pacientes Ambulatoriais , Fezes/parasitologia , Variação Genética , China/epidemiologia
3.
Dermatol Ther ; 35(11): e15822, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36098229

RESUMO

Longdan Xiegan (LDXG) decoction, an ancient Chinese herbal formula, has been widely used in treating herpes zoster. This meta-analysis aimed to evaluate whether LDXG formula as adjuvant therapy had additional benefits in acute herpes zoster patients. Two authors independently searched PubMed, Embase, Cochrane Library, China National Knowledge Infrastructure, Chinese Scientific Journal Database, and Wanfang database from their inception to July 31, 2021. Relevant randomized controlled trials (RCTs) that investigated the add-on effects of LDXG formula (decoction, capsule, or pill) in the management of acute herpes zoster were included. Nine RCTs with 821 patients were identified. A random effect model meta-analyses showed that LDXG formula plus conventional therapy significantly reduced the time to blister resolution (weighted mean difference [WMD] -1.31 days; 95% confidence intervals [CI] -1.56 to -1.06), time to crust formation (WMD -1.91 days; 95% CI -2.31 to -1.50), time to pain resolution (WMD -2.13 days; 95% CI -2.65 to -1.60), pain intensity assessed by visual analogue scale (WMD -1.13; 95% CI -2.03 to -0.24), and incidence of persistent pain (risk ratio [RR] 0.28; 95% CI 0.15-0.50) compared with the conventional therapy alone. However, the overall certainty of evidence was very low to moderate. LDXG formula as adjuvant therapy may achieve additional benefits in terms of accelerating skin healing process, relieving pain symptoms, and preventing persistent pain in acute herpes zoster patients. However, interpretation of these findings should be considered the presence of statistical heterogeneity and/or unclear risk of bias.


Assuntos
Herpes Zoster , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto , Herpes Zoster/tratamento farmacológico , Herpes Zoster/prevenção & controle , Herpesvirus Humano 3 , Terapia Combinada , Dor
4.
J Colloid Interface Sci ; 611: 739-751, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34876260

RESUMO

A dendritic PdCu/Ce0.3Zr0.7O2 (PdCu/CZ-3) catalyst with uniform spherical morphology was prepared for boosting the catalytic performance of CO2 hydrogenation to methanol (MeOH). The open dendritic pore channels and small particle sizes could reduce not only the diffuse resistance of reactants and products but also increase the accessibility between the active sites (PdCu and oxygen vacancy) and the reactants (H2 and CO2). More spillover hydrogen could be generated due to the highly dispersed PdCu active metals over the PdCu/CZ-3 catalyst. PdCu/CZ-3 can stimulate the generation of more Ce3+ cations, which is beneficial to produce more oxygen vacancies on the surface of the CZ-3 composite. Spillover hydrogen and oxygen vacancy could promote the formate and methoxy routes over PdCu/CZ-3, the primary intermediates producing MeOH. PdCu/CZ-3 displayed the highest CO2 conversions (25.5 %), highest MeOH yield (6.4 %), highest PdCu-TOFMeOH (7.7 h-1) and superior 100 h long-term stability than those of other PdCu/CexZr1-xO2 analogs and the reference PdCu/CeO2 and PdCu/ZrO2 catalysts. Density functional theory (DFT) calculations and in situ DRIFTS were performed to investigate the CO2 - MeOH hydrogenation mechanism.


Assuntos
Dióxido de Carbono , Metanol , Catálise , Hidrogenação , Oxigênio
5.
ACS Omega ; 6(36): 23558-23563, 2021 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-34549152

RESUMO

A long-time evaluation of n-butane oxidation over an industrial vanadium-phosphorus-oxygen (VPO) catalyst was implemented. The catalytic performances for n-butane oxidation during this period were obtained. It was shown that the conversion of n-butane increased with the evaluation time, but the selectivity of the maleic anhydride (MA) product decreased gradually. To investigate the crystal transformation of the VPO catalyst, the properties of fresh and evaluated VPO catalysts were measured by a series of characterization methods, including X-ray diffraction (XRD), N2 adsorption and desorption, NH3-temperature programmed desorption (TPD), Raman spectroscopy, and X-ray photoelectron spectroscopy (XPS). The results showed that the acidities and valence of vanadium increased after evaluation due to the appearance of a ß-VOPO4 phase. The crystal transformation would increase the activity for n-butane oxidation. Meanwhile, during the evaluation period, the decrease in selectivity of the MA product should be related to the decreasing percentage of Lat-O species in the VPO catalyst.

6.
Materials (Basel) ; 14(4)2021 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-33562351

RESUMO

The traditional hydrothermal method to prepare zeolite will inevitably use a large amount of water as a solvent, which will lead to higher autogenous pressure, low efficiency, and wastewater pollution. The solvent-free method can be used to synthesize various types of zeolites by mechanical mixing, grinding, and heating of solid raw materials, which exhibits the apparent advantages of high yield, low pollution, and high efficiency. This review mainly introduces the development process of solvent-free synthesis, preparation of hierarchical zeolite, morphology control, synthesis mechanism and applications of solvent-free methods. It can be believed that solvent-free methods will become a research focus and have enormous industrial application potential.

7.
J Hazard Mater ; 411: 125127, 2021 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-33485219

RESUMO

Density functional theory calculations are performed to investigate the hydrodenitrogenation (HDN) mechanism of quinoline over different Ni-promoted MoS2 edges. Based on the calculations, the hydrogenation and ring-opening reaction pathways are explored systematically, and the structure-activity relationship of different active sites is discussed in detail. In the hydrogenation reaction process, the 100% Ni-promoted M-edge and 50% Ni-promoted S-edge are favorable for the formations of 5,6,7,8-tetrahydroquinoline and 1,2,3,4-tetrahydroquinoline, respectively. Furthermore, the 100% Ni-promoted M-edge is more preferable for the generation of decahydroquinoline rather than the 50% Ni-promoted S-edge. In the denitrogenation reaction step, the 100% Ni-promoted M-edge is beneficial for the formation of ortho-propylaniline and 2-propylcyclohexylamine, while 50% Ni-promoted S-edge is only conducive to the formation of 2-propylcyclohexylamine. Therefore, it can be concluded that both hydrogenation derivatives and denitrogenation products exhibit strong dependence on the active phase morphology, meaning that multiple active sites can be involved in one catalytic HDN cycle.

8.
ACS Appl Mater Interfaces ; 12(36): 40404-40414, 2020 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-32805841

RESUMO

Novel dendritic micro-mesoporous TS-1/dendritic mesoporous silica nanoparticle (DMSN) composites (TD) were assembled by TS-1 nanocrystals with ultrasmall particle size and strong acidity. TS-1 seeds and DMSNs were composited via the Ti-O-Si chemical bond, which stimulate the generation of Brønsted (B) and Lewis (L) acids. The spillover d-electrons produced by the Ti element of TS-1 seeds produced a spillover of d-electrons, which could interact with the surface of MoS2 phases, thereby reducing Mo-S interactions and create sulfur vacancies that are favorable for dibenzothiophene (DBT) and 4,6-dimethyldibenzothiophene (4,6-DMDBT) hydrodesulfurization (HDS) reactions. The increased amount of B&L acid of NiMo/TD-2.0 with cetyltrimethylammonium bromide/sodium salicylate molar ratio of 2.0 played an important role in facilitating the hydrogenation (HYD) route of DBT HDS and the isomerization (ISO) route of 4,6-DMDBT HDS, which is more favorable for the reduction of steric hindrance of DBT and 4,6-DMDBT reactants in the HDS reaction process. The NiMo/TD-2.0 catalyst exhibited the highest turnover frequency (TOF) value and HDS reaction rate constant (kHDS) of DBT and 4,6-DMDBT due to its ultrasmall particle size, uniform spherical dendritic morphology, strong B&L acidity, and good stacking degree.

9.
ACS Omega ; 5(25): 15576-15585, 2020 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-32637833

RESUMO

A series of mesoporous materials of SBA-16 were in situ incorporated into ZSM-5 crystallites via a two-step self-assemble method, and hydrodesulfurization (HDS) catalysts were prepared on the corresponding ZSM-5/SBA-16 (ZS) composites. The characterization results indicated that ZSM-5 nanoseeds were fabricated into the silica framework of the ZS composites, and the three-dimensional Im3m cubic structure of SBA-16 was retained simultaneously. In addition, the ZS series materials possessed open pores and large surfaces, which would facilitate the diffusion of reactants in the mesoporous channels. Moreover, the introduction of ZSM-5 seeds into composites could enhance the acidities of supports. As a result, the NiMo/ZS series catalysts exhibited high activities for DBT HDS processes. The NiMo/ZS-160 catalyst exhibited the highest catalytic efficiency (96.5%), which was apparently attributed to the synergistic contributions of the physicochemical properties of ZS supports and the dispersion states of active metals. Correspondingly, DBT HDS reactions over the NiMo/ZS series catalysts mainly proceeded via a hydrogenation desulfurization route that benefitted from the enhanced acidities especially the total Brønsted acid.

10.
Small ; 16(29): e2002091, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32567241

RESUMO

The large particle sizes, inert frameworks, and small pore sizes of mesoporous silica nanoparticles greatly restrict their application in the acidic catalysis. The research reports a simple and versatile approach to synthesize walnut-like mesoporous silica nanospheres (WMSNs) with large tunable pores and small particle sizes by assembling with Beta seeds. The as-synthesized Beta-WMSNs composite materials possess ultrasmall particulate sizes (70 nm), large radial mesopores (≈30 nm), and excellent acidities (221.6 mmol g-1 ). Ni2 P active phase is supported on the surface of Beta-WMSNs composite materials, and it is found that the obtained composite spherical materials can reduce the Ni2 P particle sizes from 8.4 to 4.8 nm with the increasing amount of Beta seeds, which can provide high accessibilities of reactants to the active sites. Furthermore, the unique large pores and ultrasmall particle sizes of Beta-WMSNs samples facilitate the reduction of the diffusion resistance of reactants due to the short transporting length, thus the corresponding Ni2 P/Beta-WMSNs composite catalysts show the excellent hydrogenating activity compared to the pure Ni2 P/WMSNs catalyst.

11.
Nanoscale ; 11(33): 15519-15529, 2019 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-31393491

RESUMO

Herein, a series of wrinkled silica nanoparticles with hierarchical pore (HPWSNs) supports were successfully prepared by dual-templating, and the special wrinkle pore structures in the monodisperse HPWSN samples were found to be beneficial for reducing the diffusion resistance of macromolecular aromatic compounds and achieving high dispersion of Ni2P active phases. Moreover, the distance between wrinkles in silica nanoparticles could be easily tuned by changing the ratios of SDS/CTAB through charge-reversed interactions. It was found that the Ni2P/HPWSNs-0.13 catalyst with smallest Ni2P particles had highest surface area and biggest pore volume. Furthermore, the Ni2P/HPWSNs-0.13 catalyst exhibited highest naphthalene hydrogenation conversion as well as 99.9% selectivity to decalin at 320 °C. To correlate the internal relationship between the macroscopic catalytic performance in the experiment and the atomic chemistry in the microscopic point of view, DFT calculations were performed, and the results showed that stronger adsorptions of naphthalene and tetralin occurred over the Ni(2) sites than those over the Ni(1) sites. Therefore, it can be concluded that the superior catalytic activity of the Ni2P/HPWSNs-0.13 catalyst is due to the synergistic effect of the center-radical framework structure and the small sizes of Ni2P particles, which are conducive to exposing more Ni(2) sites on the support surface, thus inducing more H for the naphthalene hydrogenation reaction.

12.
Cancer Lett ; 448: 84-93, 2019 04 28.
Artigo em Inglês | MEDLINE | ID: mdl-30742941

RESUMO

Combining antibody-drug conjugates (ADCs) with targeted small-molecule inhibitors can enhance antitumor effects beyond those attainable with monotherapy. In this study, we investigated the therapeutic combination of a CD30-targeting ADC (anti-CD30-lidamycin [LDM]) with a small-molecule inhibitor (crizotinib) of nucleophosmin-anaplastic lymphoma kinase NPM-ALK in CD30+/ALK+ anaplastic large cell lymphoma (ALCL). In vitro, anti-CD30-LDM showed strong synergistic antiproliferative activity when combined with crizotinib. Furthermore, treatment with anti-CD30-LDM plus crizotinib resulted in a stronger induction of cell apoptosis than monotherapy with either treatment. Western blot analysis revealed that ERK1/2 phosphorylation was increased in response to anti-CD30-LDM-induced DNA damage. Interestingly, the addition of crizotinib inhibited the expression of phosphorylated ERK1/2 and further augmented anti-CD30-LDM-mediated apoptosis, providing a potential synergistic mechanism for DNA-damaging agents combined with NPM-ALK inhibitors. In Karpas299 and SU-DHL-1 xenograft models, anti-CD30-LDM plus crizotinib was more effective in inhibiting tumor growth than either treatment alone. This research demonstrated for the first time that the combination of anti-CD30-LDM and crizotinib exhibits a synergistic inhibitory effect in tumor cells. These results provide scientific support for future clinical evaluations of anti-CD30-LDM, or other DNA-damaging agents, combined with NPM-ALK inhibitors.


Assuntos
Antineoplásicos/farmacologia , Crizotinibe/farmacologia , Antígeno Ki-1/metabolismo , Linfoma Anaplásico de Células Grandes/tratamento farmacológico , Inibidores de Proteínas Quinases/farmacologia , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Humanos , Linfoma Anaplásico de Células Grandes/metabolismo , Proteínas Tirosina Quinases/antagonistas & inibidores , Receptores Proteína Tirosina Quinases/metabolismo
13.
J Environ Sci (China) ; 65: 1-7, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29548380

RESUMO

A Ce0.3TiOx oxide carrier was synthesized via a sol-gel process, and Ce0.3TiOx supported metal (M=Cd, Mn, Fe, W, Mo) oxide catalysts were prepared by the method of incipient-wetness impregnation. The catalysts were characterized by means of X-ray diffraction (XRD), Brunauer-Emmett-Teller (BET) analysis, scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared (FT-IR) spectroscopy, UV-Vis diffuse reflectance spectroscopy (UV-Vis DRS), and Temperature-programmed reduction with H2 (H2-TPR). The catalytic activities for de-NOx were evaluated by the NH3-SCR reaction. Among all the catalysts tested, the 2wt.% Cd/Ce0.3TiOx catalyst exhibited the best NH3-SCR performance, with a wide temperature window of 250-450°C for NO conversion above 90%. Moreover, the catalyst showed N2 selectivity greater than 99% from 200 to 450°C.


Assuntos
Modelos Químicos , Óxido Nítrico/química , Titânio/química , Amônia/química , Cério/química , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Oxirredução , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura , Difração de Raios X
14.
RSC Adv ; 8(25): 13750-13754, 2018 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-35539321

RESUMO

Composites of zeolite beta microspheres@nanosized HKUST-1 and micro-octahedron-shaped HKUST-1@nanosized zeolite beta were fabricated to remove thiophene from model oil. The two composite materials exhibited a higher adsorption capacity and faster adsorption rate than their corresponding mechanical mixture of HKUST-1 and zeolite beta when the sulfur concentration was at around 100 ppmw.

15.
RSC Adv ; 8(48): 27565-27573, 2018 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-35540006

RESUMO

Zirconium modified mesoporous materials were successfully synthesized by different methods including direct synthesis and post synthesis (grafting and impregnating). Meanwhile, the corresponding catalysts were prepared. A series of techniques, including small-angle X-ray scattering (SAXS), transmission electron microscopy (TEM) and pyridine adsorption Fourier-transform infrared (Py-IR), were used to characterize the properties of supports and catalysts. The results of SASX and TEM characterization proved that all the modified materials retained the well-ordered mesoporous structure from the FDU-12 material. N2 adsorption-desorption results showed that the Zr-FDU-12 material obtained by direct synthesis (Zr-in-F) possessed higher specific surface area (709 m2 g-1), pore volume (0.65 cm3 g-1) and larger pore size (18.7 nm) than the Zr-FDU-12 materials obtained by the post synthesis. According to the characterization result of UV-Vis, Zr-in-F exhibited better dispersion of Zr species than materials obtained by the post synthesis. It was found that the incorporation of Zr species not only increased acidities but also enhanced the sulfidities of the Mo species. All the catalysts were evaluated for their activities in the hydrodesulfurization of dibenzothiophene, and the NiMo/Zr-in-F catalyst exhibited the best catalytic performance (97.3%), attributed to its higher specific surface area, larger pore size, higher sulfidity, and more acidic sites.

16.
RSC Adv ; 8(51): 28879-28890, 2018 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-35548022

RESUMO

Porous support materials were prepared by assembling primary and secondary ZSM-5 structural units into a well-ordered mesoporous framework. The materials possessed both ZSM-5 microporous building units and mesoporous structure were used as supports for the preparation of hydrodesulfurization (HDS) catalysts. The materials and their corresponding catalysts were characterized by XRD, FTIR, 27Al MAS NMR, TEM, N2 adsorption-desorption, Py-FTIR, H2-TPR, Raman, and HRTEM techniques. The pore structures of the composite materials were modulated by adjusting the molar ratio of butanol/P123 (BuOH/P123) and then, the influences of BuOH/P123 on the catalytic performance in the HDS of dibenzothiophene (DBT) and diesel oil were systematically studied. The results showed that butanol has a big influence on the structure of the micro-mesoporous material, whereby different micro-mesoporous structures, such as the p6mm hexagonal structure or Ia3̄d cubic structure, were formed with different butanol addition amounts. The composite ZK-3 (BuOH/P123 = 100) possessed the best surface area and pore structure. Therefore, the NiMo/ZK-3 catalyst showed the highest catalytic activity in the HDS of DBT with a BP selectivity of 72.1% due to its excellent textural property, moderate MSI, relatively high B/L ratios, and highly dispersed NiMoS active phases. Moreover, the NiMo/AZK-3 catalyst exhibited excellent catalytic performance in the HDS of diesel oil.

17.
Chem Commun (Camb) ; 52(65): 10068-71, 2016 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-27458616

RESUMO

Nanosheet ZSM-5 zeolite with highly exposed (010) crystal planes demonstrates high reactivity and good anti-coking stability for the catalytic cracking of n-heptane, which is attributed to the synergy of high external surface area and acid sites, fully accessible channel intersection acid sites, and hierarchical porosity caused by the unique morphology.

18.
Nanoscale ; 7(25): 10918-24, 2015 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-26054526

RESUMO

A novel catalyst that consists of sub-nanosized Pt particles within hierarchically porous ZSM-5/SBA-15 materials was synthesized. This catalyst exhibited high stability and a hierarchically porous structure of a micro-mesoporous composite and possessed a high density of active sites by confinement of sub-nanosized Pt particles within small-pore zeolites, showing high catalytic properties for the hydrogenation of 1,3-butadiene and cyclooctadiene at room temperature.


Assuntos
Nanopartículas Metálicas/química , Platina/química , Silanos/química , Dióxido de Silício/química , Zeolitas/química , Butadienos/análise , Butadienos/química , Butadienos/metabolismo , Ciclo-Octanos/análise , Ciclo-Octanos/química , Ciclo-Octanos/metabolismo , Hidrogenação , Platina/metabolismo
19.
J Environ Sci (China) ; 31: 74-80, 2015 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-25968261

RESUMO

Selective catalytic reduction technology using NH3 as a reducing agent (NH3-SCR) is an effective control method to remove nitrogen oxides. TiO2-supported vanadium oxide catalysts with different levels of Ce and Sb modification were prepared by an impregnation method and were characterized by X-ray diffractometer (XRD), Brunauer-Emmett-Teller (BET), Transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FT-IR), UV-Vis diffuse reflectance spectroscopy (UV-Vis DRS), Raman and Hydrogen temperature-programmed reduction (H2-TPR). The catalytic activities of V5CexSby/TiO2 catalysts for denitration were investigated in a fixed bed flow microreactor. The results showed that cerium, vanadium and antimony oxide as the active components were well dispersed on TiO2, and the catalysts exhibited a large number of d-d electronic transitions, which were helpful to strengthen SCR reactivity. The V5CexSby/TiO2 catalysts exhibited a good low temperature NH3-SCR catalytic activity. In the temperature range of 210 to 400°C, the V5CexSby/TiO2 catalysts gave NO conversion rates above 90%. For the best V5Ce35Sb2/TiO2 catalyst, at a reaction temperature of 210°C, the NO conversion rate had already reached 90%. The catalysts had different catalytic activity with different Ce loadings. With the increase of Ce loading, the NO conversion rate also increased.


Assuntos
Amônia/química , Antimônio/química , Cério/química , Titânio/química , Compostos de Vanádio/química , Catálise , Microscopia Eletrônica de Transmissão , Oxirredução , Análise Espectral/métodos , Difração de Raios X
20.
Sci Rep ; 4: 7276, 2014 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-25450726

RESUMO

Zeolite fibers have attracted growing interest for a range of new applications because of their structural particularity while maintaining the intrinsic performances of the building blocks of zeolites. The fabrication of uniform zeolite fibers with tunable hierarchical porosity and further exploration of their catalytic potential are of great importance. Here, we present a versatile and facile method for the fabrication of hierarchical ZSM-5 zeolite fibers with macro-meso-microporosity by coaxial electrospinning. Due to the synergistic integration of the suitable acidity and the hierarchical porosity, high yield of propylene and excellent anti-coking stability were demonstrated on the as-prepared ZSM-5 hollow fibers in the catalytic cracking reaction of iso-butane. This work may also provide good model catalysts with uniform wall thickness and tunable porosity for studying a series of important catalytic reactions.

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