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1.
J Environ Manage ; 364: 121366, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38870786

RESUMO

An urban wilderness (UW) portrays a coupled relationship between natural dominance and human management in urban spaces. Superior ecosystem services support sustainable urban development. Systematic assessments of the status, changes, and trends of urban wilderness ecosystem services (UWESs) are a debated and complex issue in the field of ecology despite their importance as key components for ensuring the sustainable development of human society. We aimed to analyze the scientific literature on UWESs published between 2000 and 2022. Hence, we used bibliometric methods to comprehensively understand the research lineages, hotspots, and trends in UWESs. We found that the research has roughly encompassed two phases: initial exploration (2000-2011)and rapid growth (2012-2022). The number of publications has shown a continuous growth trend; the research hotspots include UWs compared with urban greenfield ecosystems, the spatio-temporal dynamics of UWs, ecosystem services and value assessments, and the coupling and linkage between ecosystem maintenance and human health. We summarized relevant trends for the concept of harmonious coexistence between human beings and nature, focusing on spatio-temporal dynamics and multidisciplinary integration as well as reinforcing the link with human health. This study can serve as a reference for demonstrating the value of UWESs and their practical application in a UW.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Meio Selvagem
2.
Animals (Basel) ; 13(20)2023 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-37893909

RESUMO

The objectives of this study were to identify the risk regions of wild boar incidents in China and to draw a risk map. Risk maps can be used to plan the prioritization of preventive measures, increasing management effectiveness from both a short- and a long-term perspective. We used a web crawler (web information access technology) to obtain reports of wild boar incidents from China's largest search engine (Baidu) and obtained 196 valid geographic locations of wild boar incidents from the reports. Subsequently, a system of environmental variables-with climate, topography, landscape, and human disturbance as the main variable types-was constructed, based on human-land-system thinking. Finally, the Maxent model was applied to predict the risk space of wild boar incidents in China by integrating the geographic location information for wild boar incidents with the environmental variables. We observed that the types of environmental variables that contributed to wild boar incidents were in the descending order of climate (40.5%) > human disturbance (25.2%) > landscape (24.4%) > topography (9.8%). Among the 14 environmental variables, annual precipitation, the GDP index, and the mean annual temperature were the main environmental variables. The distance from woodland, distance from cultivated land, and elevation were the secondary environmental variables. The response curves of the environmental variables demonstrated that the highest probability of wild boar incidents occurred when the annual average temperature was 16 °C, the annual precipitation was 800 mm, and the altitudes were 150 m and 1800 m. The probability of wild boar incidents decreased with an increase in the distance from cultivated and forested land, and increased sharply and then levelled off with an increase in the GDP index. Approximately 12.18% of China was identified as being at a high risk of wild boar incidents, mainly on the eastern side of the Huhuanyong Line.

3.
PLoS One ; 18(3): e0282474, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36857382

RESUMO

One of the basic assumptions of spatial theory is formulated in Waldo Tobler's first law of geography: "everything is related to everything else, but near things are more related than distant things." However, as internet space is a complex virtual space independent of the real world, whether this law is applicable to things in the internet space remains to be explored in depth. Therefore, this study takes the event of Asian elephant northern migration as an example, attempts to investigate the issue of the applicability of Tobler's first law of geography to internet attention by integrating geographic methods such as spatial visualization, spatial correlation analysis, and Geo-detector. The results show that Tobler's first law of geography does not fully apply to internet attention, which does not decay with increasing distance. Geographical distance, within certain boundaries, is influenced by "identity" and "relevance", and still plays a large role in internet attention. However, once the boundaries are exceeded, the impact of geographic distance on internet attention is weakened by the intervention of influencing factors such as the degree of information technology, population, and the strength of news media publicity. Overall, the strength of news media publicity has the greatest impact on internet attention. And when it interacts with geographic proximity, it has the most significant effect on internet attention.


Assuntos
Elefantes , Animais , Geografia , Ciência da Informação , Tecnologia da Informação , Internet
4.
Turk J Gastroenterol ; 34(1): 26-34, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36511605

RESUMO

BACKGROUND: This study evaluates the effect of bowel preparation to colonoscopy time interval on quality of bowel preparation and outcomes of colonoscopy. METHODS: Studies were identified after a literature search in electronic databases and were selected for inclusion based on precise eligibility criteria. Meta-analyses of proportions were performed to achieve overall bowel preparation adequacy and adenoma/polyp detection rates. Odds ratios depicting associations between bowel preparation quality and bowel preparation to colonoscopy time were pooled to achieve an overall estimate. RESULTS: Twenty studies (10 341 individuals subjected to colonoscopy) were included. Bowel preparation adequacy rate was higher with shorter (94% [95% CI: 91, 97]) than with longer (84% [95% CI: 79, 89]) interval between bowel preparation and colonoscopy. In a subgroup analysis, <5, 6-10, 11-20, and >20 hours intervals were associated with 94% [95% CI: 92, 97], 92% [95% CI: 86, 96], 85% [95% CI: 77, 91], and 85% [95% CI: 75, 92] adequacy rates, respectively. A pooled analysis of odds ratios also showed that bowel preparations adequacy was significantly better with shorter bowel preparation to colonoscopy time (odds ratio 1.69 [95% CI: 1.23, 2.15]). There was no significant difference in adenoma detection rate between shorter (18% [95% CI: 9, 29]) and longer (19% [95% CI: 15, 22]) bowel preparation to colonoscopy intervals. Polyp detection rate was higher with shorter (47% [95% CI: 27, 68]) than with longer (30% [95% CI: 24, 38]) bowel preparation to colonoscopy interval. CONCLUSION: A shorter interval between bowel preparation and colonoscopy led to a higher bowel preparation adequacy rate which was also associated with a higher polyp detection rate.


Assuntos
Catárticos , Colonoscopia , Humanos , Adenoma/diagnóstico , Catárticos/uso terapêutico , Colonoscopia/estatística & dados numéricos , Razão de Chances , Pólipos/diagnóstico , Fatores de Tempo , Resultado do Tratamento
5.
J Colloid Interface Sci ; 628(Pt B): 524-533, 2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-36007417

RESUMO

The sluggish kinetic of hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) severely hampers the commercial application of electrochemical water splitting, promoting the urgent exploration of high-efficient bifunctional electrocatalysts. Heteroatom doping and structure engineering have been identified as the most effective strategies to boost the catalytic activity of electrocatalysts. Herein, Mn doping and hollow structure were integrated in the design of Co-based transition metal phosphide catalyst to prepare Mn-CoP/Co2P nanotubes (denoted as Mn-CP NTs) by a facile template-free method. Confirmed by characterization analysis, the introduced Mn species were in high dispersion in the regular CoP/Co2P hollow tubular framework. Such a favorable design in composition and structure effectively boosted the catalytic activity of Mn-CP NTs toward electrochemical water splitting. The Mn-CP NTs showed superior HER and OER activity demonstrated by the low overpotentials of 82 mV (vs HER) and 309 mV (vs OER) at the current density of 10 mA cm-2, as well as the satisfactory durability. When used as both cathode and anode in electrolyzer for overall water splitting, only a low cell voltage of 1.67 V was required for the Mn-CP NTs to drive 10 mA cm-2, accompanied with excellent stability confirmed by over 50 h test.

6.
Chem Commun (Camb) ; 55(42): 5894-5897, 2019 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-31044198

RESUMO

A self-hollowing process was demonstrated for the creation of hollow MoS2 nanospheres starting from their amorphous solid precursor, which were spontaneously transformed into a hollow structure during the rearrangement of crystal lattices initiated by a high-temperature treatment, forming hollow-structured materials favorable for their application in sodium ion batteries.

7.
Small ; 15(32): e1901019, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30997739

RESUMO

As lithium-ion batteries continue to climb to even higher energy density, they meanwhile cause serious concerns on their stability and reliability during operation. To make sure the electrode materials, particularly cathode materials, are stable upon extended cycles, surface modification becomes indispensable to minimize the undesirable side reaction at the electrolyte-cathode interface, which is known as a critical factor to jeopardizing the electrode performance. This Review is targeted at a precise surface control of cathode materials with focus on the synthetic strategies suitable for a maximized surface protection ensured by a uniform and conformal surface coating. Detailed discussions are taken on the formation mechanism of the designated surface species achieved by either wet-chemistry routes or instrumental ones, with attention to the optimized electrochemical performance as a result of the surface control, accordingly drawing a clear image to describe the synthesis-structure-performance relationship to facilitate further understanding of functional electrode materials. Finally, perspectives regarding the most promising and/or most urgent developments for the surface control of high-energy cathode materials are provided.

8.
Chem Commun (Camb) ; 55(8): 1076-1079, 2019 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-30617367

RESUMO

We have reported an efficient synthetic protocol to build different hollow hybrid nanocomposites with tunable compositions, such as Au/TiO2, Pt/ZrO2, and Au/CexTi1-xO2. The noble metal nanoparticles were well encapsulated in a wall composed of the designated transition metal oxides, showing promising potential as stable catalysts as demonstrated by Pt/ZrO2 for methane combustion.

10.
Dalton Trans ; 47(37): 12843-12846, 2018 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-30141805

RESUMO

We identified that the growth kinetics of ZrO2 could be well-tuned in a CH3COOH-CH3COONa based buffer solution, which provided an efficient way to build uniform ZrO2 nanoshells on various substrates. Using this synthetic strategy, yolk-shell structured Pd@ZrO2 is demonstrated as a promising catalyst for methane oxidation.

11.
J Am Chem Soc ; 140(29): 9070-9073, 2018 07 25.
Artigo em Inglês | MEDLINE | ID: mdl-29983044

RESUMO

Hollow nanostructures of metal oxides have found broad applications in different fields. Here, we reported a facile and versatile synthetic protocol to prepare hollow metal oxide nanospheres by modulating the chemical properties in solid nanoparticles. Our synthesis design starts with the precipitation of urea-containing metal oxalate, which is soluble in water but exists as solid nanospheres in ethanol. A controlled particle hydrolysis is achieved through the heating-induced urea decomposition, which transforms the particle composition in an outside-to-inside style: The reaction starts from the surface and then proceeds inward to gradually form a water-insoluble shell of basic metal oxalate. Such a reaction-induced solubility difference inside nanospheres becomes highly efficient to create a hollow structure through a simple water wash process. A following high temperature treatment forms hollow nanospheres of different metal oxides with structural features suited to their applications. For example, a high performance anode for Li-ion intercalation pseudocapacitor was demonstrated with the hollow and mesoporous Nb2O5 nanospheres.

12.
ACS Appl Mater Interfaces ; 10(27): 22896-22901, 2018 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-29947502

RESUMO

Surface cobalt doping is an effective and economic way to improve the electrochemical performance of cathode materials. Herein, by tuning the precipitation kinetics of Co2+, we demonstrate an aqueous-based protocol to grow uniform basic cobaltous carbonate coating layer onto different substrates, and the thickness of the coating layer can be adjusted precisely in nanometer accuracy. Accordingly, by sintering the cobalt-coated LiNi0.5Mn1.5O4 cathode materials, an epitaxial cobalt-doped surface layer will be formed, which will act as a protective layer without hindering charge transfer. Consequently, improved battery performance is obtained because of the suppression of interfacial degradation.

13.
J Am Chem Soc ; 140(23): 7127-7134, 2018 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-29771119

RESUMO

K-ion batteries (KIBs) are now drawing increasing research interest as an inexpensive alternative to Li-ion batteries (LIBs). However, due to the large size of K+, stable electrode materials capable of sustaining the repeated K+ intercalation/deintercalation cycles are extremely deficient especially if a satisfactory reversible capacity is expected. Herein, we demonstrated that the structural engineering of carbon into a hollow interconnected architecture, a shape similar to the neuron-cell network, promised high conceptual and technological potential for a high-performance KIB anode. Using melamine-formaldehyde resin as the starting material, we identify an interesting glass blowing effect of this polymeric precursor during its carbonization, which features a skeleton-softening process followed by its spontaneous hollowing. When used as a KIB anode, the carbon scaffold with interconnected hollow channels can ensure a resilient structure for a stable potassiation/depotassiation process and deliver an extraordinary capacity (340 mAh g-1 at 0.1 C) together with a superior cycling stability (no obvious fading over 150 cycles at 0.5 C).

14.
Chem Commun (Camb) ; 54(42): 5326-5329, 2018 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-29736514

RESUMO

A surface doping strategy is demonstrated for the stabilization of LiMn2O4, which is achieved by the surface solid reaction between the LiMn2O4 particle and its ZnO nanoshell. The surface treated sample shows a much improved high temperature performance with evidently suppressed Mn dissolution.

15.
ACS Appl Mater Interfaces ; 9(4): 3749-3756, 2017 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-28075124

RESUMO

Ammonia-borane (NH3·BH3; AB) has been considered as an excellent chemical material for hydrogen storage. However, developing highly efficient catalysts for continuous hydrogen generation from AB is still a challenge for future fuel cell applications. The combination of Pt with Ni is an effective strategy to achieve active bimetallic nanocatalyst, and the particle size has proved to play a crucial role in determining its final activity. However, the synthesis of PtNi bimetallic catalyst in the size of highly dispersed clusters has always been a challenge. In this report, PtNi/NiO clusters coated by small-sized hollow silica (R-PtNi/NiO@SiO2) were designed for efficient hydrogen generation from the hydrolysis of ammonia-borane. The newly designed catalysis system showed extremely high activity with the initial turnover frequency value reaching 1240.3 mol of H2·mol-1 of Pt·min-1, which makes it one the most active Pt-based catalysts for this reaction. Detailed characterization by means of scanning transmission electron microscopy, X-ray photoelectron spectroscopy, energy-dispersive X-ray spectroscopy element mapping, etc. revealed that the excellent performance of R-PtNi/NiO@SiO2 is derived from the highly dispersed PtNi/NiO clusters and the reduction of extra Pt4+ on the surface of PtNi/NiO clusters to Pt0 at relatively low temperature.

16.
Chem Commun (Camb) ; 52(44): 7122-5, 2016 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-27165843

RESUMO

This communication reports that the TiO2@polydopamine nanocomposite with a core-shell structure could be a highly active photocatalyst working under visible light. A very thin layer of polydopamine at around 1 nm was found to be critical for the degradation of Rhodamine B.

17.
J Am Chem Soc ; 138(18): 5916-22, 2016 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-27096883

RESUMO

Hollow hybrid microspheres have found great potential in different areas, such as drug delivery, nanoreactors, photonics, and lithium-ion batteries. Here, we report a simple and scalable approach to construct high-quality hollow hybrid microspheres through a previously unexplored growth mechanism. Starting from uniform solid microspheres with low crystallinity, we identified that a hollowing process can happen through the progressive inward crystallization process initiated on the particle surface: the gradual encroachment of the crystallization frontline toward the core leads to the depletion of the center and forms the central cavity. We showed that such a synthetic platform was versatile and can be applicable for a large variety of materials. By using the production of Li4Ti5O12-carbon hollow hybrid microspheres as an example, we demonstrated that high-performance anode materials could be achieved through synthesis and structure control. We expect that our findings offer new perspectives in different areas ranging from materials chemistry, energy storage devices, catalysis, to drug delivery.

18.
Phys Chem Chem Phys ; 18(3): 1637-43, 2016 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-26673863

RESUMO

The crystallinity of cadmium titanate (CdTiO3) was greatly improved when synthesized under mild reaction conditions, in the presence of chloride. The highly crystalline CdTiO3 showed much enhanced photodegradation of methyl orange (MO) under simulated sunlight. CdTiO3 was characterized using X-ray diffraction (XRD), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), N2 adsorption/desorption, photoluminescence (PL), and UV/vis spectrometry. The enhanced photodegradation was attributed to the better charge separation owing to its higher crystallinity.

19.
ACS Appl Mater Interfaces ; 7(49): 27031-4, 2015 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-26619036

RESUMO

Yolk-shell structured nanomaterials have shown interesting potential in different areas due to their unique structural configurations. A successful construction of such a hybrid structure relies not only on the preparation of the core materials, but also on the capability to manipulate the outside wall. Typically, for Al2O3, it has been a tough issue in preparing it into a uniform nanoshell, making the use of Al2O3-based yolk-shell structures a challenging but long-awaited task. Here, in benefit of our success in the controlled formation of Al2O3 nanoshell, we demonstrated that yolk-shell structures with metal confined inside a hollow Al2O3 nanosphere could be successfully achieved. Different metals including Au, Pt, Pd have been demonstrated, forming a typical core@void@shell structure. We showed that the key parameters of the yolk-shell structure such as the shell thickness and the cavity size could be readily tuned. Due to the protection of a surrounding Al2O3 shell, the thermal stability of the interior metal nanoparticles could be substantially improved, resulting in promising performance for the catalytic CO oxidation as revealed by our preliminary test on Au@Al2O3.

20.
Chem Commun (Camb) ; 51(35): 7482-5, 2015 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-25827909

RESUMO

Pd nanoparticles were successfully introduced into the channels of mesoporous silica MCM-41 with their dispersion well-tuned. We identified the dual role played by CTAB, which was critical for both the micelle template and Pd grafting, leading to the formation of a highly active Pd-MCM-41 nanocomposite for catalysing the Suzuki reaction.


Assuntos
Nanopartículas Metálicas/química , Nanocompostos/química , Paládio/química , Dióxido de Silício/química , Catálise , Nanocompostos/ultraestrutura , Porosidade
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