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1.
Langmuir ; 40(22): 11353-11370, 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38771257

RESUMO

The essential role of electrolyte solutions in traditional electrochemical energy storage devices is crucial to enhancing their performance. Consequently, a wide array of electrolyte mixtures along with diverse electrodes have been extensively explored across different models of secondary batteries. Fascinatingly, the role of ethyl methyl carbonate (EMC) as a key cosolvent in the electrolyte mixture of commercial lithium-ion batteries with a graphite anode is garnering growing attention in alternative rechargeable dual-ion batteries utilizing graphite cathodes. In this context, the advancement and function of EMC as a solvent in electrolyte mixtures for lithium-ion and dual-ion batteries were extensively and thoroughly examined in this analysis, encompassing the genesis, synthesis process, and diverse characteristics for the practical uses of these batteries. Here, the review aims to guide readers in understanding EMC's function and impact as a cosolvent in electrolyte mixtures for both major secondary lithium-ion and dual-ion batteries, considering their distinct physicochemical characteristics.

2.
J Environ Manage ; 336: 117624, 2023 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-36868152

RESUMO

To mitigate aviation's carbon emissions of the aviation industry, the following steps are vital: accurately quantifying the carbon emission path by considering uncertainty factors, including transportation demand in the post-COVID-19 pandemic period; identifying gaps between this path and emission reduction targets; and providing mitigation measures. Some mitigation measures that can be employed by China's civil aviation industry include the gradual realization of large-scale production of sustainable aviation fuels and transition to 100% sustainable and low-carbon sources of energy. This study identified the key driving factors of carbon emissions by using the Delphi Method and set scenarios that consider uncertainty, such as aviation development and emission reduction policies. A backpropagation neural network and Monte Carlo simulation were used to quantify the carbon emission path. The study results show that China's civil aviation industry can effectively help the country achieve its carbon peak and carbon neutrality goals. However, to achieve the net-zero carbon emissions goal of global aviation, China needs to reduce its emissions by approximately 82%-91% based on the optimal emission scenario. Thus, under the international net-zero target, China's civil aviation industry will face significant pressure to reduce its emissions. The use of sustainable aviation fuels is the best way to reduce aviation emissions by 2050. Moreover, in addition to the application of sustainable aviation fuel, it will be necessary to develop a new generation of aircraft introducing new materials and upgrading technology, implement additional carbon absorption measures, and make use of carbon trading markets to facilitate China's civil aviation industry's contribution to reduce climate change.


Assuntos
Aviação , COVID-19 , Humanos , Dióxido de Carbono/análise , Incerteza , Pandemias , COVID-19/prevenção & controle , Desenvolvimento Econômico , China , Carbono/análise
3.
Stroke ; 47(5): 1233-1238, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-27026627

RESUMO

BACKGROUND AND PURPOSE: Most previous studies have used single-phase computed tomographic angiography to detect the spot sign, a marker for hematoma expansion (HE) in spontaneous intracerebral hemorrhage. We investigated whether defining the spot sign based on timing on perfusion computed tomography (CTP) would improve its specificity for predicting HE. METHODS: We prospectively enrolled supratentorial spontaneous intracerebral hemorrhage patients who underwent CTP within 6 hours of onset. Logistic regression was performed to assess the risk factors for HE and poor outcome. Predictive performance of individual CTP spot sign characteristics were examined with receiver operating characteristic analysis. RESULTS: Sixty-two men and 21 women with spontaneous intracerebral hemorrhage were included in this analysis. Spot sign was detected in 46% (38/83) of patients. Receiver operating characteristic analysis indicated that the timing of spot sign occurrence on CTP had the greatest area under receiver operating characteristic curve for HE (0.794; 95% confidence interval, 0.630-0.958; P=0.007); the cutoff time was 23.13 seconds. On multivariable analysis, the presence of early-occurring spot sign (ie, spot sign before 23.13 seconds) was an independent predictor not only of HE (odds ratio=28.835; 95% confidence interval, 6.960-119.458; P<0.001), but also of mortality at 3 months (odds ratio =22.377; 95% confidence interval, 1.773-282.334; P=0.016). Moreover, the predictive performance showed that the redefined early-occurring spot sign maintained a higher specificity for HE compared with spot sign (91% versus 74%). CONCLUSIONS: Redefining the spot sign based on timing of contrast leakage on CTP to determine early-occurring spot sign improves the specificity for predicting HE and 3-month mortality. The use of early-occurring spot sign could improve the selection of ICH patients for potential hemostatic therapy.


Assuntos
Hemorragia Cerebral/diagnóstico por imagem , Angiografia por Tomografia Computadorizada/normas , Hematoma/diagnóstico por imagem , Avaliação de Resultados em Cuidados de Saúde , Idoso , Idoso de 80 Anos ou mais , Angiografia por Tomografia Computadorizada/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Prognóstico , Curva ROC , Estudos Retrospectivos , Fatores de Risco , Fatores de Tempo
4.
J Colloid Interface Sci ; 673: 527-536, 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38885538

RESUMO

The highly efficient photo-oxidation of alcohols has sparked significant potential to cope with environmental pollution and the ever-increasing energy crisis. This study reports a unique Ti3C2/BiOBr (TB) heterojunction with a rich inter-face based on in situ exfoliation of MXene and subsequently anchored onto BiOBr sheets. The TB nano-composites exhibited substantially improved photo-catalytic activity towards the photo-oxidation of benzyl alcohol (BA) to benzaldehyde and achieved a formation rate of 1.73 mmol g-1 h-1, greater than pristine BiOBr. The ultra-thin inter-facial contact boosted the oxygen vacancies (Ov) and Ti3+ and possessed the most negative adsorption energy, which boosted the transfer and separation of inter-facial charge carriers and the adsorption and dissociation of BA. Overall, the successful synthesis of TB composite, along with its exceptional photo-catalytic performance, offers valuable insights for applications in green chemistry and environmental remediation.

5.
J Colloid Interface Sci ; 662: 76-86, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38340516

RESUMO

The development of novel semiconductor photo-catalysts for the efficient degradation of antibiotics poses a considerable challenge in the context of ever-increasing environmental pollution. Herein, an S-scheme photo-catalyst consisting of TiO2 quantum dots (QDs, size ∼4-6 nm) anchored on Bi2O2CO3 nano-sheets was synthesised via a facile hydrothermal protocol. TiO2/Bi2O2CO3 (TB) nano-composite exhibits enhanced photo-catalytic removal of tetracycline, achieving ∼0.0158 min-1 photo-degradation rates using visible light, which is 3- and 53-fold greater than that of pristine TiO2 and Bi2O2CO3, respectively. The theoretical calculations substantiate that the built-in electric field in the TB nano-composite is conducive to the separation and transfer of photo-excited carriers. Notably, the generated superoxide radicals rather than hydroxyl were identified as the responsible species for tetracycline degradation. In addition, the corresponding degradation pathway and eco-toxicity analysis were also elucidated. In conclusion, this work contributes valuable insights and presents a feasible approach for the fabrication of S-scheme photo-catalysts (TiO2 QDs and bismuth-based nano-materials), thereby enabling the efficient removal of water pollutants.

6.
Sci Rep ; 14(1): 4442, 2024 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-38396123

RESUMO

The timely identification of individuals at high risk for peptic ulcers (PUs) is vital in preventing gastrointestinal bleeding after antiplatelet therapy. This study was designed to determine PU risk factors and develop a risk assessment model for PU detection in the general Chinese population. In a prospective dataset, clinical data from individuals undergoing gastroscopic evaluation between April 2019 and May 2022 were recorded. PUs were defined as mucosal defects exceeding 5 mm confirmed via gastroscopy. Participants were categorized into development (April 2019 to April 2021) and validation (May 2021 to May 2022) sets based on chronological order. LASSO-derived logistic regression analysis was employed to create a score, which was further validated via temporal validation. A total of 902 patients were ultimately enrolled, 204 (22.6%) of whom had PUs based on endoscopic findings. In the development cohort (n = 631), seven independent risk factors emerged: male sex (OR = 2.35, P = 0.002), white blood cell (WBC) count (OR = 1.16, P = 0.010), red blood cell (RBC) count (OR = 0.49, P < 0.001), globulin level (OR = 0.92, P = 0.004), albumin level (OR = 0.94, P = 0.020), pepsinogen I (PGI) level (OR = 1.01, P < 0.001), and positive Helicobacter pylori (HP) antibody (OR = 2.50, P < 0.001). Using these factors, a nomogram (HAMPROW score [hazard ratio (HP) antibody, albumin, male, PGI, RBC, globulin, and WBC]) was developed for individual PU prediction. The ability of the HAMPROW score to predict survival was confirmed with AUCs of 0.854 (95% CI 0.816-0.891) and 0.833 (95% CI 0.771-0.895) in the development and validation sets, respectively. In conclusion, the HAMPROW score can be used to screen for PUs effectively in the general Chinese population, facilitating personalized early detection of high risk of gastrointestinal bleeding before antiplatelet therapy.


Assuntos
Globulinas , Infecções por Helicobacter , Helicobacter pylori , Úlcera Péptica , Humanos , Masculino , Úlcera Péptica Hemorrágica/tratamento farmacológico , Inibidores da Agregação Plaquetária/uso terapêutico , Estudos Prospectivos , Úlcera Péptica/complicações , Hemorragia Gastrointestinal/induzido quimicamente , Albuminas/uso terapêutico , China/epidemiologia , Supuração/induzido quimicamente , Supuração/complicações , Infecções por Helicobacter/tratamento farmacológico
7.
JACS Au ; 2(11): 2607-2616, 2022 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-36465539

RESUMO

Oxidative dehydrogenation of propane (ODHP) as an exothermic process is a promising method to produce propene (C3H6) with lower energy consumption in chemical industry. However, the selectivity of the C3H6 product is always poor because of overoxidation. Herein, the ODHP reaction into C3H6 on a model rutile(R)-TiO2(110) surface at low temperature via photocatalysis has been realized successfully. The results illustrate that photocatalytic oxidative dehydrogenation of propane (C3H8) into C3H6 can occur efficiently on R-TiO2(110) at 90 K via a stepwise manner, in which the initial C-H cleavage occurs via the hole coupled C-H bond cleavage pathway followed by a radical mediated C-H cleavage to the C3H6 product. An exceptional selectivity of ∼90% for C3H6 production is achieved at about 13% propane conversion. The mechanistic model constructed in this study not only advances our understanding of C-H bond activation but also provides a new pathway for highly selective ODHP into C3H6 under mild conditions.

8.
J Phys Chem Lett ; 12(6): 1708-1717, 2021 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-33561346

RESUMO

Selective C-C coupling of oxygenates via aldol condensation has the potential to produce useful chemicals from aldehydes and ketones. Here we report a combined experimental and theoretical study on the aldol condensation of unbranched aldehydes (CnH2n+1-CHO, n = 1-4) on rutile (R)-TiO2(100)-(1 × 1). Experimental results show that the R-TiO2(100)-(1 × 1) surface has a very high reactivity and selectivity for aldol product formation from tested aldehydes at room temperature. Theoretical calculations indicate that the CH3CHO enolization and the aldol dehydration occur with low energy barriers, and the 3-butanolal intermediate adsorbs on R-TiO2(100)-(1 × 1) stably, suggesting that the surface has a "modest" acid-base strength for efficient crotonaldehyde formation. The adsorption configuration of CH3CHO and surface structure of R-TiO2(100)-(1 × 1) may contribute to the exclusive selectivity of (E)-crotonaldehyde formation, which provides us a deep insight into the high selectivity of aldol condensation of aldehydes on the TiO2 catalyst.

9.
Ecol Evol ; 9(12): 7143-7156, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31380039

RESUMO

The arthropod communities are influenced by both local conditions and features of the surrounding landscape. Landscape complexity and stand factors may both influence arthropod communities in poplar forests, but the multiscale effects of these factors on poplar defoliators and natural enemies are still poorly understood. We collected poplar arthropods at 30 sampling sites within five forest landscapes in Xinjiang, China, and assessed whether landscape complexity and stand factors influence species abundance and diversity of poplar arthropods. Landscape complexity was quantified by several independent metrics of landscape composition, configuration, and connectivity at three spatial scales. We also determined the most powerful explanatory variables and the scale effect of each arthropod. Results found that landscape complexity and stand factors had different effects on different poplar arthropod communities. Landscape complexity promoted natural enemies at different spatial scales, but it inhibited the population of poplar defoliators at the scale of 200 m. Specifically, the abundance and diversity of all defoliators decreased with increasing proportion of nonhost plants. Landscape diversity only had a negative effect on defoliator abundance. The shape complexity of habitat patches increased the abundance of carabid beetles but reduced the abundance of green leafhoppers and migratory locusts. The abundance and diversity of predators increased with increasing structural connectivity of forest landscape. Additionally, both the abundance and diversity of all defoliators were positively correlated with the average height of herbaceous plants. Diversity of all defoliators increased with increasing size of host trees. The distance from sampling site to the nearest village positively influenced the abundance and diversity of all predators. Arthropod abundance and diversity in poplar forests were driven by stand factors and landscape complexity. Therefore, maintaining complex shape and structural connectivity of habitat patches and keeping poplar stands away from the village are crucial for management of forest landscape to enhance natural enemies. And in order to reduce the abundance of defoliators in poplar forest, the diversity of surrounding habitat types should be promoted within 200 m radii.

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