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1.
Reprod Biol Endocrinol ; 22(1): 61, 2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38783347

RESUMO

BACKGROUND: Prospective observational studies have demonstrated that the machine learning (ML) -guided noninvasive chromosome screening (NICS) grading system, which we called the noninvasive chromosome screening-artificial intelligence (NICS-AI) grading system, can be used embryo selection. The current prospective interventional clinical study was conducted to investigate whether this NICS-AI grading system can be used as a powerful tool for embryo selection. METHODS: Patients who visited our centre between October 2018 and December 2021 were recruited. Grade A and B embryos with a high probability of euploidy were transferred in the NICS group. The patients in the control group selected the embryos according to the traditional morphological grading. Finally, 90 patients in the NICS group and 161 patients in the control group were compared statistically for their clinical outcomes. RESULTS: In the NICS group, the clinical pregnancy rate (70.0% vs. 54.0%, p < 0.001), the ongoing pregnancy rate (58.9% vs. 44.7%, p = 0.001), and the live birth rate (56.7% vs. 42.9%, p = 0.001) were significantly higher than those of the control group. When the female was ≥ 35 years old, the clinical pregnancy rate (67.7% vs. 32.1%, p < 0.001), ongoing pregnancy rate (56.5% vs. 25.0%, p = 0.001), and live birth rate (54.8% vs. 25.0%, p = 0.001) in the NICS group were significantly higher than those of the control group. Regardless of whether the patients had a previous record of early spontaneous abortion or not, the live birth rate of the NICS group was higher than that of the control group (61.0% vs. 46.9%; 57.9% vs. 34.8%; 33.3% vs. 0%) but the differences were not statistically significant. CONCLUSIONS: NICS-AI was able to improve embryo utilisation rate, and the live birth rate, especially for those ≥ 35 years old, with transfer of Grade A embryos being preferred, followed by Grade B embryos. NICS-AI can be used as an effective tool for embryo selection in the future.


Assuntos
Aprendizado de Máquina , Taxa de Gravidez , Humanos , Feminino , Gravidez , Adulto , Estudos Prospectivos , Transferência de Embrião Único/métodos , Diagnóstico Pré-Implantação/métodos , Transferência Embrionária/métodos , Infertilidade Feminina/terapia , Infertilidade Feminina/genética , Infertilidade Feminina/diagnóstico , Resultado do Tratamento , Infertilidade/terapia , Infertilidade/diagnóstico , Infertilidade/genética
2.
iScience ; 27(5): 109745, 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38706839

RESUMO

Zeolite-encaged metal nanoparticles (NPs) catalysts are emerging as a new frontier owing to their superior ability to stabilize the structure and catalytic performance in the thermal and environmental catalytic reaction. However, the pore size below 2 nm of the conventional zeolites usually limits the accessibility of metal active sites. Herein, Co-Cu NPs of about 2.5-3.5 nm were uniformly encapsulated in the intracrystalline mesoporous Silicalite-1 (S-1) through alkali-treatment ligand-assisted strategy. The obtained sample (termed CoxCu1-x@HS-1) exhibited efficient activity and stability in the ammonia borane hydrolysis with the highest TOF value of 21.46 molH2·molMe-1·min-1. UV-vis DRS spectra indicated that intracrystalline mesopores have greatly improved the openness and accessibility of the active sites, thus improving their catalytic performance. The introduction of Cu regulates the electronic properties of Co, further increasing hydrogen production activity. This research creates new prospects to design other high-performance hierarchical porous zeolite-confined metal/metal oxide catalysts.

3.
iScience ; 27(3): 109064, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38375219

RESUMO

Titanium silicate zeolite (TS-1) is widely used in the research on selective oxidations of organic substrates by H2O2. Compared with the chlorohydrin process and the hydroperoxidation process, the TS-1 catalyzed hydroperoxide epoxidation of propylene oxide (HPPO) has advantages in terms of by-products and environmental friendliness. This article reviews the latest progress in propylene epoxidation catalyzed by TS-1, including the HPPO process and gas phase epoxidation. The preparation and modification of TS-1 for green and sustainable production are summarized, including the use of low-cost feedstocks, the development of synthetic routes, strategies to enhance mass transfer in TS-1 crystal and the enhancement of catalytic performance after modification. In particular, this article summarizes the catalytic mechanisms and advanced characterization techniques for propylene epoxidation in recent years. Finally, the present situation, development prospect and challenge of propylene epoxidation catalyzed by TS-1 were prospected.

4.
J Colloid Interface Sci ; 658: 22-31, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38091795

RESUMO

Designing non-precious catalysts to synergistically achieve a facilitated exposure of abundant active sites is highly desired but remains a significant challenge. Herein, a hetero-structured catalyst CoP-Co supported on porous g-C3N4 nanosheets (CoP-Co/CN-I) was prepared by pyrolysis and P-inducing strategy. The optimal catalyst achieves a turnover frequency (TOF) of 26 min-1 at room temperature and the apparent activation energy (Ea) is 35.5 kJ·mol-1. The catalytic activity is ranked top among the non-precious metal phosphides or the other supports. Meanwhile, the catalytic activity has no significant decrease even after 5 cycles. The CoP/Co interfaces provide richly exposed active sites, optimize hydrogen/water absorption free energy via electronic coupling, and thus improve the catalytic activity. The experimental results reveal that the CoP/Co heterojunction improves the catalytic activity due to the construction of dual-active sites. This research facilitates the innovative construction of non-noble metal catalysts to meet industrial demand for heterogeneous catalysis.

5.
Org Biomol Chem ; 21(36): 7410-7418, 2023 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-37661852

RESUMO

Due to the ubiquity of carbonyl compounds and the abundance of nickel on the earth, nickel-catalyzed decarbonylation has garnered increasing attention in recent years. This type of reaction has seen significant developments in various aspects; however, certain challenges concerning reactivity, selectivity, and transformation efficiency remain pressing and demand urgent resolution. In this study, we employed DFT calculations to investigate the mechanism of nickel-catalyzed decarbonylation reactions involving lactones, as well as the effects of phosphine ligands. Mechanically, Ni(0) first activates the C(acyl)-O bond of the lactone, followed by a decarbonylation step, and ultimately results in reductive elimination under carbonyl coordination to yield the product. Through a comprehensive examination of the electronic and steric effects of the phosphine ligands, we deduced that the electronic effect of the ligand plays a dominant role in the decarbonylation reaction. By enhancing the electron-withdrawing ability of the ligand, the energy barrier of the entire reaction can be significantly reduced. The obtained insights should be valuable for understanding the detailed mechanism and the role of phosphine ligands in nickel catalysis. Moreover, they offer crucial clues for the rational design of more efficient catalytic reactions.

6.
Environ Geochem Health ; 45(8): 6231-6243, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37280504

RESUMO

The stabilization of heavy metals in soil has been increasingly applied in China in recent years due to its quick effect and low cost. In this study, loess and chicken manure compost (a commercial organic fertilizer) were used to stabilize Cd in slightly polluted fluvo-aquic soil from the North China Plain, and the driving factors for stabilization were investigated through ridge regression. The additives significantly reduced the total concentration of Cd in soil through dilution. The addition of loess and compost increased carbonates and organic matter in soil, respectively. This caused exchangeable Cd to be transformed to fractions bound to carbonates or organic matter, thereby decreasing the concentration of Cd in the roots and leaves of Chinese chive. The decreasing exchangeable Cd in soil was the direct cause of decreased uptake of Cd by plants, and the increasing fractions bound to carbonates or organic matter were indirect influencing factors. However, adding loess decreased soil fertility and retarded plant growth. The addition of compost compensated for these defects. This study suggests that the combined addition of loess and chicken manure compost was able to effectively reduce the total concentration and phytoavailability of Cd in soil and guarantee crop yield and quality.


Assuntos
Cádmio , Cebolinha-Francesa , Compostagem , Poluentes do Solo , Animais , Cádmio/química , Galinhas , Cebolinha-Francesa/química , Esterco , Solo , Poluentes do Solo/análise
7.
Small ; 19(43): e2303031, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37356067

RESUMO

Bimetallic Nanoalloy catalysts have diverse uses in clean energy, sensing, catalysis, biomedicine, and energy storage, with some supported and unsupported catalysts. Conventional synthetic methods for producing bimetallic alloy nanoparticles often produce unalloyed and bulky particles that do not exhibit desired characteristics. Alloys, when prepared with advanced nanoscale methods, give higher surface area, activity, and selectivity than individual metals due to changes in their electronic properties and reduced size. This review demonstrates the synthesis methods and principles to produce and characterize highly dispersed, well-alloyed bimetallic nanoalloy particles in relatively simple, effective, and generalized approaches and the overall existence of conventional synthetic methods with modifications to prepare bimetallic alloy catalysts. The basic concepts and mechanistic understanding are represented with purposely selected examples. Herein, the enthralling properties with widespread applications of nanoalloy catalysts in heterogeneous catalysis are also presented, especially for Hydrogen Evolution Reaction (HER), Oxidation Reduction Reaction (ORR), Oxygen Evolution Reaction (OER), and alcohol oxidation with a particular focus on Pt and Pd-based bimetallic nanoalloys and their numerous fields of applications. The high entropy alloy is described as a complicated subject with an emphasis on laser-based green synthesis of nanoparticles and, in conclusion, the forecasts and contemporary challenges for the controlled synthesis of nanoalloys are addressed.

8.
Environ Sci Pollut Res Int ; 30(29): 74372-74385, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37208508

RESUMO

In this study, the spatiotemporal distribution of microplastic deposition was investigated through ordinary Kriging interpolation, and the potential sources of microplastic deposition were identified by using Hybrid Single-Particle Lagrangian Integrated Trajectory model. The results showed that the total deposition flux of microplastics ranged from 79.5 to 810.0 p/(m2·d). The shapes of microplastics could be divided into 4 shapes: fiber, fragment, film, and pellet. Seven polymer types of microplastics were identified, including polyamide (PA), polyethylene (PE), polyethylene terephthalate (PET), polymethyl methacrylate (PMMA), polypropylene (PP), polystyrene (PS), and polyvinyl chloride (PVC). Most microplastics were tiny and small sizes (≤ 500 µm) and colorless. Through model analysis and survey, microplastic deposition came from the study region, and the potential sources might be plastic products and wastes. The seasons with the highest and lowest total deposition flux were summer (535.5 p/(m2·d)) and winter (197.5 p/(m2·d)), respectively. The months of the highest and lowest total deposition flux were June 2021 (681.4 p/(m2·d)) and January 2022 (112.2 p/(m2·d)), respectively. Most fibers (PET, PA, PP) and fragments (PP) were distributed in populous areas such as commercial centers and residential areas. Abundant fragments (PET, PS, PE) and films (PE, PVC) were distributed around salvage stations. Almost all of the pellets (PE, PMMA) were found in the factory. Our results suggested that the temporal distribution of microplastic deposition was influenced by precipitation and mean temperature of air, and the spatial distribution of microplastic deposition was influenced by sources and population density.


Assuntos
Microplásticos , Poluentes Químicos da Água , Plásticos , Polimetil Metacrilato , Poluentes Químicos da Água/análise , Monitoramento Ambiental , Polipropilenos , Poliestirenos , Polietileno/análise , Nylons , China , Polietilenotereftalatos
9.
Front Oncol ; 12: 941797, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36185197

RESUMO

Background: Related studies have shown that it is safe for cancer patients to undergo assisted reproduction. However, studies on whether a history of cancer affects long-term reproductive outcomes in women who undergo assisted reproductive technology (ART) are scarce. In this study, we evaluated the long-term reproductive outcomes of patients with malignant tumors undergoing ART treatment and explored the impact of malignancy history on ART outcomes. Methods: This retrospective study analyzed the clinical outcomes of patients with malignant tumors undergoing their first in vitro fertilization/intracytoplasmic sperm injection (IVF/ICSI) cycles compared with those of age-matched healthy infertile women at Fujian Maternity and Child Health Hospital between January 2003 and October 2020. We evaluated ovarian stimulation outcome, the pregnancy rate, the live birth rate, the risk of adverse obstetric outcomes and birth outcomes. Results: This study included 59 patients in the cancer group for data analysis who had a history of malignancy. By matching, a total of 118 healthy infertile women were included in the control group. No statistically significant association was found in terms of age, duration of infertility, BMI, or insemination type between the two groups of patients. Thyroid cancer(45.8%) and gynecologic malignancies (44.07%) were the major cancer types in this study. There were statistically significant differences in the antral follicle count (AFC) (12.00 ± 7.86 vs. 14.90 ± 8.71, P=0.033), length of ovarian stimulation (9.98 ± 2.68 vs. 11.42 ± 2.43, P=0.033) and endometrial thickness on the trigger day (10.16 ± 3.11 vs. 10.84 ± 2.17, P<0.001) between the two groups. The total gonadotropin dose, number of oocytes retrieved, fertilization rate, cleavage rate, high-quality embryo rate, blastocyst rate and first-time embryo-transfer (ET) implantation rate were nonsignificantly lower in the cancer group than in the control group (P>0.05). There were no significant differences in the clinical pregnancy rate per ET cycle (32% vs. 40.39%, P=0.156), live birth rate per ET cycle (27% vs. 35.96%, P=0.119), miscarriage rate per ET cycle (5% vs. 4.43%, P=0.779), or preterm delivery rate per ET cycle (11.11% vs. 17.80%, P=0.547) between the two groups. Additionally, regression analysis showed that a history of malignancy was not a risk factor for reproductive outcomes. Conclusions: Overall, it is feasible for women with a history of cancer to conceive using ART is feasible and their long-term reproductive outcomes are similar to these of healthy infertile women. A history of cancer does not decrease the number of retrieved oocytes, increase the risk of adverse obstetric outcomes or affect birth outcomes.

10.
ACS Omega ; 7(30): 26289-26297, 2022 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-35936401

RESUMO

Ga-doped ZSM-5 zeolites were directly synthesized by a facile one-step hydrothermal method without organic templates and calcination and then investigated in the cyclohexene hydration reaction. The structure, component, textural properties, and acidity of the as-prepared samples were examined by X-ray diffraction (XRD), scanning electron microscopy (SEM), X-ray fluorescence (XRF), Brunauer-Emmett-Teller (BET), ammonia temperature-programmed desorption (NH3-TPD), pyridine-chemisorbed IR (Py-IR), and 71Ga, 27Al, 29Si, and 1H magic-angle spinning (MAS) NMR techniques. The characterization results showed that the introduction of Ga atoms into the ZSM-5 zeolite framework is much easier than Al atoms and beneficial to promote the formation of small-sized crystals. The number of Brønsted acid sites of Ga-doped ZSM-5 samples obviously increased compared with Ga0-ZSM-5. Additionally, the highest cyclohexanol yield (10.1%) was achieved over the Ga3-ZSM-5 sample, while the cyclohexanol yield of the Ga0-ZSM-5 sample was 8.6%. This result indicated that the improved catalytic performance is related to its larger external surface area, smaller particle size, and more Brønsted acid sites derived from Si-OH-Al and Si-OH-Ga of Ga3-ZSM-5. Notably, the green route reduces harmful gas emission and provides a basis for doping other heteroatoms to regulate the catalytic performance of zeolites, especially in industrial production.

11.
Food Chem ; 393: 133400, 2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-35688089

RESUMO

Improving the characteristics of low salt proteins is the key to the gel properties of low-salt meat products which are demanded by people nowadays. The present study focused on the effects of KGM concentrations on the changes in structure and gelling properties of low-salt myofibrillar protein (MP). KGM addition (≤0.75 %) irrespective of salt concentration modified secondary and tertiary structures of MPs, enhanced the binding capacity of Troponin-T and Tropomyosin, augmented the gelling behavior of proteins, and remarkably improved the storage modulus (G') and gel strength of heat-induced MP gels. Interestingly, KGM addition in low salt condition showed the transformation of the all-gauche SS conformation into gauche-gauche-trans and trans-gauche-trans, and the partial transformation of α-helices into ß-sheets. overall, KGM modified the structure of low salt MPs and thus improved the gel properties of low salt MPs. Therefore, KGM is recommended for low-salt meat processing to enhance the MP gelling potential.


Assuntos
Coloides , Mananas , Géis/química , Humanos , Mananas/química , Conformação Proteica , Reologia , Cloreto de Sódio , Cloreto de Sódio na Dieta
12.
Small ; 18(22): e2107417, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35508765

RESUMO

The rational design of the interface structure between nitride and oxide using the same metallic element and correlating the interfacial active center with a determined catalytic mechanism remain challenging. Herein, a Co4 N-Co3 O4 interface structure is designed to determine the effect of interfacial active centers on hydrogen generation from ammonia borane. An unparalleled catalytic activity toward H2 production with a turnover frequency up to 79 min-1 is achieved on Co4 N-Co3 O4 @C catalyst for ten recycles. Experimental analyses and theoretical simulation suggest that the atomic interface-exciting effect (AieE) is responsible for the high catalytic activity. The Co4 N-Co3 O4 interface facilitates the targeted adsorption and activation of NH3 BH3 and H2 O molecules to generate H* and H2 . The two active centers of Co(N)* and Co(O)* at the Co4 N-Co3 O4 interface activate NH3 BH3 and H2 O, respectively. This proof-of-concept research on AieE provides important insights regarding the design of heterogeneous catalysts and promotes the development of the nature and regulation of energy chemical conversion.


Assuntos
Cobalto , Óxidos , Amônia , Catálise , Cobalto/química , Hidrogênio/química , Óxidos/química
13.
Ecotoxicol Environ Saf ; 233: 113353, 2022 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-35240502

RESUMO

The deposition is an important process of microplastics transporting from atmosphere to water and soil. But the spatial and temporal distribution of microplastics in urban atmospheric deposition and its influencing factors are poorly understood. The current study investigated the possible sources, spatial and temporal distribution, and potential ecological risk of microplastics in deposition from the valley basin of Lanzhou city during the COVID-19 pandemic (from February to August, 2020). The deposition flux of microplastics was 353.83 n m-2 d-1. Most plastic samples were small sized (50~500 µm) and transparent. The dominant chemical composition and shapes were PET, fragments and fibers, respectively. A modified method was conducted to identify the sources of microplastics, and the local sources were suggested as the main possible sources. The distribution of microplastics investigated through the inverse distance weight interpolation showed spatial variation and temporal differentiation which was dominated by the human activity. The rainfall also affected the temporal distribution. The preliminary assessment indicated higher potential ecological risk of microplastics in deposition. This study suggested the dominant effect of human activity on the source and distribution of atmospheric microplastic deposition in city.


Assuntos
COVID-19 , Poluentes Químicos da Água , China , Monitoramento Ambiental , Humanos , Microplásticos , Pandemias , Plásticos , SARS-CoV-2 , Poluentes Químicos da Água/análise
14.
Dalton Trans ; 50(38): 13476-13482, 2021 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-34492669

RESUMO

Germanium-based materials attract more interest as anodes for lithium-ion batteries, stemming from their physical and chemical advantages. However, these materials inevitably undergo capacity attenuation caused by significant volumetric variation in repeated electrochemical processes. Herein, we designed 3D porous Ge/N-doped carbon nanocomposites by the encapsulation of 3D porous Ge in a nitrogen-doped carbon matrix (denoted as 3D porous Ge/NC). The 3D porous structure can accommodate the volume change during alloying/dealloying processes and improve the penetration of the electrolyte. Furthermore, the doping of N in the carbon framework could introduce more defects and active sites, which can also contribute to electron transportation and lithium-ion diffusion. The half-cell test found that at a current density of 1 C (1 C = 1600 mA h g-1), the specific capacity stabilized at 917.9 mA h g-1 after 800 cycles; and the specific capacity remained at 542.4 mA h g-1 at 10 C. When assembled into a 3D porous Ge/NC//LiFePO4 full cell, the specific capacity was stabilized at 101.3 mA h g-1 for 100 cycles at a current density of 1 C (1 C = 170 mA h g-1), and the cycle specific capacity was maintained at 72.6 mA h g-1 at a high current density of 5 C. This work develops a low-cost, scalable and simple strategy to improve the electrochemical performance of these alloying type anode materials with huge volume change in the energy storage area.

15.
ACS Omega ; 6(20): 13015-13023, 2021 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-34056452

RESUMO

The synthesis of a TS-1 zeolite with high-content framework Ti and small particles has been developed by adding NH4HCO3 and suspended seeds as an assistant. With the addition of NH4HCO3, the Hofmann decomposition of the tetrapropylammonium cation (TPA+) decreased, and the framework Ti content of the zeolite increased first and then decreased while the particle became larger. With the assistance of suspended seeds, the TS-1 synthesized under a low-alkalinity system possesses small particle size and high-content framework Ti, and it shows the best catalytic activity among the prepared catalysts. Because the decomposition of TPA+ decreased, the mother liquid could be reused in the next run of preparation. Even though the recycled mother liquid was reused five times, all obtained TS-1 samples exhibited similar catalytic performances in propylene epoxidation. This work provides an efficient process for preparing TS-1 with good catalytic performance and reduces the discharge of the waste liquid.

16.
RSC Adv ; 11(46): 28632-28642, 2021 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-35478593

RESUMO

In this work, a polypyrrole (PPy)/TiO2 nanocomposite coating was fabricated by the direct electropolymerization of pyrrole on annealed TiO2 nanoparticles and evaluated as a novel direct immersion solid phase microextraction (DI-SPME) fiber coating for extraction of trace amounts of pollutants in environmental water samples. The functionalized fiber is mechanically and chemically stable, and can be easily prepared in a highly reproducible manner. The effects of the pyrrole monomer concentration, polymerization voltage and polymerization time on the fiber were discussed. Surface morphological and compositional analyses revealed that the composite coating of nano polypyrrole and titanium dioxide nanoparticles (TiO2NPs) uniformly doped the Ti substrate. The as-fabricated fiber exhibited good extraction capability for phenolic compounds in combination with high performance liquid chromatography-UV detection (HPLC-UV). At the optimum SPME conditions, the calibration curves were linear (R 2 ≥ 0.9965). LODs and LOQs of less than 0.026 µg L-1 and 0.09 µg L-1 , respectively, were achieved, and RSDs were in the range 3.5-7.2%. The results obtained in this work suggest that PPy/TiO2 is a promising coating material for future applications of SPME and related sample preparation techniques.

17.
RSC Adv ; 9(5): 2386-2394, 2019 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-35520480

RESUMO

In this study, titanium silicalite (TS-1) crystals containing Al were synthesized using aluminosilicate MFI zeolites as seeds in a tetrapropylammonium bromide (TPAB)-ethanolamine (EA) system. The TS-1 containing Al possessed large size, large L b value and higher catalytic activity in cyclohexanone ammoximation. Larger L b value would endow the TS-1 crystals with better mechanical strength and erosion resistance. The introduction of an Al atom into the TS-1 crystals resulted in the production of more acid sites and a bit strong Brönsted acid sites; these acid sites were more favorable to the catalytic performances in cyclohexanone ammoximation.

18.
ChemSusChem ; 12(2): 426-433, 2019 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-30560572

RESUMO

Solar steam generation is a highly promising technology for harvesting solar energy and desalination. Here, a new solar steam generation system is introduced based on a surface-modified polyurethane sponge with bilayered structures for efficient solar steam generation. The top layer, coated with polydimethylsiloxane-modified graphite powder, serves as light-to-heat conversion layer with a broad optical absorption, whereas the lower part of the sponge acts as a thermal insulator with a low thermal conductivity in the wet state (0.13882 W m-1 K-1 ). In addition, the strong hydrophobic wettability of the top layer (water contact angle: 148°) enables self-floating behavior on water, which is beneficial for practical applications. The results show that compared with a silver-nanoparticle-doped sponge and an acid-etched sponge doped with silver nanoparticles the graphite-modified sponge (GS) exhibits the highest evaporation efficiency of 73.3 % under 1 kW m2 irradiation, which is 2.6 times that of pure water and far higher than that of untreated polyurethane sponge (36.0 %). The GS shows excellent stability, and its evaporation efficiency remains unchanged even after immersion in water for one month. Based on its cost-efficient, simple, and scalable manufacturing process, excellent mechanical stability, and high recyclability, the GS shows great potential as an efficient photothermal material for a wide range of large-scale applications such as solar steam generation, light absorption, heat localization, and seawater desalination.

19.
ACS Appl Mater Interfaces ; 4(9): 4776-80, 2012 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-22900618

RESUMO

In this article, TiO(2)-Carbon-rGO (GCT) three-component composite material has been constructed by anchoring TiO(2) nanoparticles (NPs) encapsulated in carbon shells onto reduced graphene oxide (rGO) sheets. The structure of GCT was characterized by X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), N(2) adsorption-desorption isotherms, and transmission electron microscopy (TEM). This material shows a superior retention as the anode materials in lithium ion battery with a specific discharge capacity of 188 mA h g(-1) in the initial cycle and 158 mA h g(-1) after 100 cycles.


Assuntos
Carbono/química , Grafite/química , Lítio/química , Titânio/química , Fontes de Energia Elétrica , Técnicas Eletroquímicas , Óxidos/química
20.
ACS Appl Mater Interfaces ; 4(8): 4106-12, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22775061

RESUMO

The oxidation-resistant acidic resins are of great importance for the catalytic oxidation systems. In this paper, the oxidatively stable acidic resins are obtained from the cation ion exchange resins (CIERs) through the thermal treatment in N(2) atmosphere. The structure and properties of the thermally treated CIERs were characterized by chemical analysis, Fourier transform infrared (FT-IR) spectra, acid capacity measurement and scanning electron microscope (SEM). The thermally treated CIERs possess high acid capacity up to 4.09 mmol g(-1). A partial carbonization is observed in the thermal treatment process of CIERs, but the morphology of resin spheres maintains well. The as-prepared CIERs are used as solid acids to assist the hydrogen peroxide oxidation of cyclohexene to adipic acid (ADA) with tungstic acid as the catalyst precursor. The improved yields of ADA in the recycling reaction are obtained in the presence of acidic CIERs. Meanwhile, the unproductive decomposition of H(2)O(2) is effectively suppressed. The high yields of ADA (about 81%) are kept by the thermally treated CIERs even after the fifth cycle. The thermally treated CIERs exhibit excellent acid-catalytic performance and possess remarkable oxidation-resistant capability.


Assuntos
Adipatos/química , Carbono/química , Oxigênio/química , Polímeros/química , Ácidos , Catálise , Cicloexenos/química , Temperatura Alta , Peróxido de Hidrogênio/química , Microscopia Eletrônica de Varredura/métodos , Modelos Químicos , Nitrogênio/química , Espectroscopia de Infravermelho com Transformada de Fourier/métodos
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