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1.
J Am Chem Soc ; 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38816747

RESUMO

Lithium metal batteries face problems from sluggish charge transfer at interfaces, as well as parasitic reactions between lithium metal anodes and electrolytes, due to the strong electronegativity of oxygen donor solvents. These factors constrain the reversibility and kinetics of lithium metal batteries at low temperatures. Here, a nonsolvating cosolvent is applied to weaken the electronegativity of donor oxygen in ether solvents, enabling the participation of anionic donors in the solvation structure of Li+. This strategy significantly accelerates the desolvation process of Li+ and reduces the side effects of solvents on interfacial transport and stability. The designed anion-aggregated electrolyte has a unique temperature-insensitive solvation structure and enables lithium metal anodes to achieve a high average Coulombic efficiency at room temperature and -20 °C. A high-loading LiFePO4||Li cell exhibited high reversibility with a 100% capacity retention after 150 cycles at room temperature, -20, and -40 °C. The practical 1 Ah-level LiFePO4||Li pouch-cell delivered 81% and 61% of the capacity at room temperature when charged and discharged at -20 and -40 °C, respectively. This strategy of constructing temperature-insensitive solvation by electronegativity regulation offers a novel approach for developing electrolytes of low-temperature batteries.

2.
Small ; 20(2): e2305464, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37658520

RESUMO

The utilization of layered oxides as cathode materials has significantly contributed to the advancement of the lithium-ion batteries (LIBs) with high energy density and reliability. However, the structural and interfacial instability triggered by side reactions when charged to high voltage has plagued their practical applications. Here, this work reports a novel multifunctional additive, id est, 7-Anilino-3-diethylamino-6-methyl fluoran (ADMF), which exhibits unique characteristics such as preferential adsorption, oxygen scavenging, and electropolymerization protection for high-voltage cathodes. The ADMF demonstrates the capability to ameliorate the growth of cathode-electrolyte interphase (CEI), effectively diminishing the dissolution of transition metal (TM) ions, reducing the interface impedance, and facilitating the Li+ transport. As a result, ADMF additive with side reaction-blocking ability significantly enhances the cycling stability of MCMB||NCM811 full-cells at 4.4 V and MCMB||LCO full-cells at 4.55 V, as evidenced by the 80% retention over 600 cycles and 87% retention after 750 cycles, respectively. These findings highlight the potential of the additive design strategy to modulate the CEI chemistry, representing a new paradigm with profound implications for the development of next-generation high-voltage LIBs.

3.
Environ Res ; 207: 112205, 2022 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-34653408

RESUMO

Since the COVID-19 pandemic, ventilation on transport has been improved to control the aerosol transmission. We utilized portable monitors to measure real-time concentrations of PM10, PM2.5, PM1.0 and black carbon (BC) on six modes of transport and estimate personal exposures under the epidemic prevention. The mean concentrations of PM10, PM2.5, PM1.0 and BC measured on transport were 18.8 ± 19.4, 16.6 ± 16.5, 12.2 ± 10.8 and 4.1 ± 6.9 µg/m3, respectively. It reduced PM levels on subway to apply the full fresh air mode rather than partial recirculation mode. Airplane had the lowest concentrations and the highest decay rates, implying the most efficient ventilation and filtration. PM were higher on intra-city transport than inter-city, and significantly increased on arrival at stations. BC and BC/PM ratios were higher on road transport than rail transport, indicating the contribution of exhaust emissions. The ventilation mode to exchange air with the outside and the positive association between concentrations and decay rates on high-speed train suggested filtration efficiency should be improved simultaneously with enhancing ventilation. Wearing facemasks on transport further protects passengers against PM exposure, which reduced personal exposure concentrations on four modes of transport lower than 10 µg/m3, the World Health Organization guideline.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , COVID-19 , Poluentes Atmosféricos/análise , Poluição do Ar/análise , Poluição do Ar/prevenção & controle , China , Monitoramento Ambiental , Humanos , Pandemias , Material Particulado/análise , SARS-CoV-2
4.
Indoor Air ; 32(1): e12962, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34841578

RESUMO

Fine particulate matter (PM2.5 ) concentrations show high variations in different microenvironments indoors, which has considerable impact on risk management. However, the real-time variations of PM2.5 exposure associated with per activity/microenvironment and intra-variation among family members remain undefined. In this study, real-time monitors were used to collect real-time PM2.5 data in different microenvironments in 32 households in urban community of China. Peak concentrations of PM2.5 were found in kitchen. The parallel levels of PM2.5 household indoor and outdoor indicated the benefit of clean energies use. To validly assess the health risk of individuals, we proposed a novel method to estimate the real-time exposure of all residents and firstly investigate the intra-variation of PM2.5 exposure among family members. The member who is responsible for cooking in the family had the maximum PM2.5 exposure. The ratios among intraindividual variations demonstrated children usually had lower exposure compared to the adults as they stayed more time in lower polluted microenvironments such as living room and bedroom. The exposure intensity in living room was above 1.0 for most residents, indicating it is warranted to alleviate the air pollution in living room. This study firstly focused on the intra differences of PM2.5 exposure among family members and provided a new insight for indoor air pollution management. The results suggested when adopting measures to reduce exposure, the microenvironments pattern of each member should be taken into consideration. Future work is welcomed to move another big step on this issue to protect the human health.


Assuntos
Poluentes Atmosféricos , Poluição do Ar em Ambientes Fechados , Adulto , Poluentes Atmosféricos/análise , Poluição do Ar em Ambientes Fechados/análise , Criança , China , Culinária/métodos , Monitoramento Ambiental/métodos , Humanos , Material Particulado/análise , População Rural
5.
Ecotoxicol Environ Saf ; 247: 114274, 2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-36356530

RESUMO

Inhalation exposure to polycyclic aromatic hydrocarbons (PAHs) from indoor solid fuel combustion poses a high health risk, and PAHs bound to particles with smaller sizes (e.g., PM1.0, aerodynamic diameter ≤ 1.0 µm) should be of particular concern since they can penetrate deep into pulmonary alveoli. However, PAHs bound to PM1.0 was less studied compared with PAHs in total suspended particles or PM2.5. In this study, multiple provincial field measurements were conducted to investigate 28 PAHs bound to PM1.0 in rural Chinese homes. Daily averaged PM1.0-PAH28 concentrations ranged from 27 ng/m3 to 3795 ng/m3 (median: 233 ng/m3) and from 10 ng/m3 to 2978 ng/m3 (median: 87 ng/m3) in indoor and outdoor air, respectively. Higher concentrations were found in northern China in winter due to increased solid fuels consumption for space heating. The ambient pollution was lower during the non-heating season in Eastern China, where clean energy was preferred. Highly toxic congeners were more abundant in indoor air compared with outdoor air. The results of source apportionment revealed that solid fuel combustion was the primary contributor to rural household PM1.0-PAHs, but other sources such as vehicles cannot be overlooked. The transition to cleaner energy can reduce the indoor PM1.0-PAH28 and BaPeq-28 concentrations by 87% and 98%, respectively, and more efficient reduction was observed for highly toxic congeners. The estimated Incremental Lifetime Cancer Risk (ILCR) based on PM1.0-PAH28 ranged from 4.6 × 10-5 to 3.4 × 10-2, far exceeding the acceptable level of 10-6. Over 60% of the ILCR could be attributed to inhalation exposure during childhood and adolescence.


Assuntos
Hidrocarbonetos Policíclicos Aromáticos , Adolescente , Humanos , Acidentes , Povo Asiático , Exposição por Inalação/efeitos adversos , China
6.
Molecules ; 27(7)2022 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-35408465

RESUMO

Lactic acid bacteria (LAB) produce antimicrobial substances that could potentially inhibit the growth of pathogenic and food spoilage microorganisms. Lacticaseibacillus rhamnosus XN2, isolated from yak yoghurt, demonstrated antibacterial activity against Bacillus subtilis, B. cereus, Micrococcus luteus, Brochothrix thermosphacta, Clostridium butyricum, S. aureus, Listeria innocua CICC 10416, L. monocytogenes, and Escherichia coli. The antibacterial activity was estimated to be 3200 AU/mL after 30 h cultivation. Time-kill kinetics curve showed that the semi-purified cell-free supernatants (CFS) of strain XN2 possessed bactericidal activity. Flow cytometry analysis indicated disruption of the sensitive bacteria membrane by semi-purified CFS, which ultimately caused cell death. Interestingly, sub-lethal concentrations of semi-purified CFS were observed to reduce the production of α-haemolysin and biofilm formation. We further investigated the changes in the transcriptional level of luxS gene, which encodes signal molecule synthase (Al-2) induced by semi-purified CFS from strain XN2. In conclusion, L. rhamnosus XN2 and its bacteriocin showed antagonistic activity at both cellular and quorum sensing (QS) levels. Finally, bacteriocin was further purified by reversed-phase high-performance liquid chromatography (RP-HPLC), named bacteriocin XN2. The amino acid sequence was Met-Lue-Lys-Lys-Phe-Ser-Thr-Ala-Tyr-Val.


Assuntos
Bacteriocinas , Lacticaseibacillus rhamnosus , Animais , Antibacterianos , Bovinos , Staphylococcus aureus , Iogurte
7.
Indoor Air ; 31(4): 1072-1083, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33569809

RESUMO

BACKGROUND: Household air pollution (HAP) from residential combustion considerably affects human health in rural China. Large-scale population migration and rural lifestyle changes during the Spring Festival are supposed to change the household air pollution and health risks; however, limited field study has determined its impacts on HAP and short-term health outcomes. METHODS: A field study was conducted in rural areas of Southern China before and during the Spring Festival to explore the associations between HAP and blood pressure considering different factors such as cooking fuel, heating fuel, and smoking. Stationary real-time PM2.5 monitors were used to measure PM2.5 concentrations of the kitchen, living room, and yard of 156 randomly selected households. Personal exposure to PM2.5 was calculated based on the results of stationary samplers and corresponding time local residents spent in different microenvironments, and one adult resident was recruited of each family for the blood pressure measurement. RESULTS: Both personal exposure to PM2.5 and blood pressures of local residents increased during Spring Festival compared to the days before the holiday. Based on generalized linear model coupled with dominance analysis approach, it was found that personal PM2.5 exposure was positively associated with the factors of population size and the types of cooking and heating fuels with the relative contributions of approximately 82%, and systolic blood pressure (SBP, 100-120 mmHg as normal range for adults) was positively and significantly associated with personal PM2.5 exposures with the relative contribution of 11%. CONCLUSION: The findings in this study demonstrated that Spring Festival can give rise to increase of HAP and hypertension risks, also related to tremendous solid fuel use, suggesting further policy making on promoting cleaner energy in rural areas and more attention on large population migration during national holidays.


Assuntos
Poluentes Atmosféricos , Poluição do Ar em Ambientes Fechados , Poluição do Ar , Adulto , Poluentes Atmosféricos/análise , Poluição do Ar/análise , Poluição do Ar em Ambientes Fechados/análise , Pressão Sanguínea , China , Culinária , Monitoramento Ambiental , Férias e Feriados , Humanos , Material Particulado/análise , População Rural
8.
Ecotoxicol Environ Saf ; 211: 111959, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33486383

RESUMO

Indoor biomass burning produces large amounts of small particles and hazardous contaminants leading to severe air pollution and potentially high health risks associated with inhalation exposure. Personal samplers provide more accurate estimates of inhalation exposure. In this study, inhalation exposure to size-segregated particles and particulate polycyclic aromatic hydrocarbons (PAHs) for the biomass user was studied by deploying personal samplers. The study found that daily PM2.5 inhalation exposure level was as high as 121 ± 96 µg/m3, and over 84% was finer PM1.0. For PAHs, the exposure level was 113 ± 188 ng/m3, with over 77% in PM1.0. High molecular weight PAHs with larger toxic potentials enriched in smaller particles resulting in much high risks associated with PAHs inhalation exposure. Indoor exposure contributed to ~80% of the total inhalation exposure as a result of high indoor air pollution and longer residence spent indoor. The highest exposure risk was found for the male smoker who conducted cooking activities at home.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar/estatística & dados numéricos , Monitoramento Ambiental , Exposição por Inalação/estatística & dados numéricos , Material Particulado/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Poluição do Ar/análise , Poluição do Ar em Ambientes Fechados/análise , Biomassa , Carvão Mineral/análise , Culinária , Poeira , Habitação , Humanos , Exposição por Inalação/análise , Tamanho da Partícula , População Rural , Tibet
9.
Langmuir ; 30(14): 3949-56, 2014 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-24650361

RESUMO

A new monitoring technique, which combines real-time in-situ CCD camera observation and reflectance spectra measurement, has been developed to study the growing and drying processes of evaporation-induced self-assembly (EISA). Evolutions of the reflectance spectrum and CCD camera images both reveal that the entire process of polystyrene (PS) EISA contains three stages: crack-initiation stage (T1), crack-propagation stage (T2), and crack-remained stage (T3). A new phenomenon, the red-shift of stop-band, is observed when the crack begins to propagate in the monitored window of CCD camera. Deformation of colloidal spheres, which mainly results in the increase of volume fraction of spheres, is applied to explain the phenomenon. Moreover, the modified scalar wave approximation (SWA) is utilized to analyze the reflectance spectra, and the fitting results are in good agreement with the evolution of CCD camera images. This new monitoring technique and the analysis method provide a good way to get insight into the growing and drying processes of PS colloidal self-assembly, especially the crack propagation.

10.
Biosens Bioelectron ; 248: 115997, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38183792

RESUMO

Real-time sensing of reactive oxygen species (ROS) and timely scavenging of excessive ROS in physiological environments are critically important in the diagnosis and prevention of ROS-related diseases. To solve the mismatch problem between conventional rigid ROS biosensors and biological tissues in terms of both modulus and composition, here, we present a flexible ferrocene-based hydrogel biosensor designed for oxidative stress detection and antioxidation treatment. The hydrogel was fabricated through a supramolecular assembly of ferrocene-grafted polyethylenimine (PEI-Fc), sodium alginate (SA), and polyvinyl alcohol (PVA). Multiple non-covalent interactions, including electrostatic interactions between PEI-Fc and SA, hydrophobic interactions and π-π stacking among ferrocene groups, and the PVA crystalline domain, synergistically improve the mechanical properties of the PVA/SA/PEI-Fc hydrogel. The flexible PVA/SA/PEI-Fc hydrogel biosensor exhibited a broad detection range for hydrogen peroxide (H2O2), from 0 to 120 µM, using the differential pulse voltammetry method. Furthermore, the hydrogel demonstrated effective ROS scavenging and oxygen generation performance, desirable biocompatibility, and satisfactory antibacterial activity, making it suitable for biological interfaces. In vitro studies revealed that the PVA/SA/PEI-Fc hydrogel could monitor H2O2 concentration in the proximity of inflammatory cells, and effectively scavenge ROS to protect cells from oxidative stress damage. This all-in-one multifunctional hydrogel, integrating both sensing and treatment functions, holds great promise for clinical applications in the diagnosis and management of ROS-related diseases.


Assuntos
Técnicas Biossensoriais , Compostos Ferrosos , Hidrogéis , Hidrogéis/química , Antioxidantes , Peróxido de Hidrogênio , Metalocenos , Espécies Reativas de Oxigênio , Técnicas Biossensoriais/métodos , Estresse Oxidativo , Alginatos/química
11.
J Hazard Mater ; 470: 134238, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38608586

RESUMO

China, as one of the largest global producers and consumers of per- and poly-fluoroalkyl substances (PFASs), faces concerning levels of PFAS pollution in soil. However, knowledge of their occurrence in agricultural soils of China on the national scale remains unknown. Herein, the first nationwide survey was done by collecting 352 soil samples from 31 provinces in mainland China. The results indicated that the Σ24PFASs concentrations were 74.3 - 24880.0 pg/g, with mean concentrations of PFASs in decreasing order of legacy PFASs > emerging PFASs > PFAS precursors (640.2 pg/g, 340.7 pg/g, and 154.9 pg/g, respectively). The concentrations in coastal eastern China were distinctly higher than those in inland regions. Tianjin was the most severely PFASs-contaminated province because of rapid urban industrialization. This study further compared the PFAS content in monoculture and multiple cropping farmland soils, finding the concentrations of PFASs were high in soils planted with vegetable and fruit monocultures. Moreover, a positive matrix factorization (PMF) model was employed to identify different sources of PFASs. Fluoropolymer industries and aqueous film-forming foams were the primary contributors. The contributions from different emission sources varied across the seven geographical regions. This study provides new baseline data for prevention and control policies for reducing pollution.

12.
Int J Biol Macromol ; 268(Pt 1): 131582, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38631589

RESUMO

Matrix metalloproteinase 9 (MMP-9) plays an important role in wound healing. However, overexpression of MMP-9 leads to the degradation of the newly formed extracellular matrix, which delays wound healing, ultimately leading to chronic wounds. Therefore, timely monitoring of the MMP-9 activity using simple, cost-effective methods is important to prevent the formation of chronic wounds. In this work, ferrocene-modified MMP-9 cleavage peptide (Fc-MG) modified carboxymethyl chitosan hydrogels were prepared as electrochemical biosensors. In the presence of MMP-9, the peptide chain is sheared, and the electrochemically active ferrocene segment is released. Therefore, analyzing the electrochemical activity of hydrogels using differential pulse voltammetry (DPV) can be used to determine MMP-9 activity. The results showed that the DPV peaks were correlated with the MMP-9 concentration in phosphate-buffered saline (PBS, pH 7.4) and Dulbecco's modified Eagle's medium (DMEM). Specifically, the corresponding coefficient of determination (R2) were 0.918 and 0.993. The limit of detections were 73.08 ng/mL and 131.71 ng/mL, respectively. Compared with the enzyme-linked immunosorbent assay, the hydrogel biosensor determined the concentration of MMP-9 in solution with simpler steps. This study demonstrates a novel strategy based on Fc-MG-modified hydrogels to monitor MMP-9 activity in cell secretion samples and shows the potential application in chronic wounds.


Assuntos
Técnicas Biossensoriais , Quitosana , Técnicas Eletroquímicas , Compostos Ferrosos , Hidrogéis , Metaloproteinase 9 da Matriz , Metalocenos , Quitosana/química , Quitosana/análogos & derivados , Metaloproteinase 9 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/análise , Metalocenos/química , Hidrogéis/química , Compostos Ferrosos/química , Técnicas Biossensoriais/métodos , Técnicas Eletroquímicas/métodos , Humanos
13.
Adv Mater ; : e2401965, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38631703

RESUMO

Tailorable lithium (Li) nucleation and uniform early-stage plating is essential for long-lifespan Li metal batteries. Among factors influencing the early plating of Li anode, the substrate is critical, but a fine control of the substrate structure on a scale of ≈10 nm has been rarely achieved. Herein, a carbon consisting of ordered grids is prepared, as a model to investigate the effect of substrate structure on the Li nucleation. In contrast to the individual spherical Li nuclei formed on the flat graphene, an ultrauniform and nuclei-free Li plating is obtained on the ordered carbon with a grid size smaller than the thermodynamical critical radius of Li nucleation (≈26 nm). Simultaneously, an inorganic-rich solid-electrolyte-interphase is promoted by the cross-sectional carbon layers of such ordered grids which are exposed to the electrolyte. Consequently, the carbon grids with a grid size of ≈10 nm show a favorable cycling stability for more than 1100 cycles measured at 2 mA cm-2 in a half cell. With LiNi0.8Co0.1Mn0.1O2 as cathode, the assembled full cell with a cathode capacity of 3 mAh cm-2 and a negative/positive ratio of 1.67 demonstrates a stable cycling for over 130 cycles with a capacity retention of 88%.

14.
J Hazard Mater ; 470: 134284, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38615648

RESUMO

Neonicotinoid insecticide (NEO) residues in agricultural soils have concerning and adverse effects on agroecosystems. Previous studies on the effects of farmland type on NEOs are limited to comparing greenhouses with open fields. On the other hand, both NEOs and microplastics (MPs) are commonly found in agricultural fields, but their co-occurrence characteristics under realistic fields have not been reported. This study grouped farmlands into three types according to the covering degree of the film, collected 391 soil samples in mainland China, and found significant differences in NEO residues in the soils of the three different farmlands, with greenhouse having the highest NEO residue, followed by farmland with film mulching and farmland without film mulching (both open fields). Furthermore, this study found that MPs were significantly and positively correlated with NEOs. As far as we know this is the first report to disclose the association of film mulching and MPs with NEOs under realistic fields. Moreover, multiple linear regression and random forest models were used to comprehensively evaluate the factors influencing NEOs (including climatic, soil, and agricultural indicators). The results indicated that the random forest model was more reliable, with MPs, farmland type, and total nitrogen having higher relative contributions.

15.
Zookeys ; 1203: 173-187, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38855786

RESUMO

Based on a molecular phylogenetic analysis and morphological comparison, a new species of mountain pitviper, Ovophisjenkinsi sp. nov., is described. The new species was collected in Yingjiang County, Yunnan Province, China. It can be distinguished from congeneric species by the following characters: (1) internasals in contact or separated by one small scale; (2) second supralabial entire and bordering the loreal pit; (3) dorsal scales in 23 (25)-21 (23, 25)-19 (17, 21) rows; (4) 134-142 ventrals; (5) 40-52 pairs of subcaudals; (6) third supralabial larger than fourth in all examined specimens of Ovophisjenkinsi sp. nov.; (7) deep orange-brown or dark brownish-grey markings on dorsal head surface; (8) background color of dorsal surface deep orange-brown or dark brownish-grey; (9) both sides of dorsum display dark brown trapezoidal patches; (10) scattered small white spots on dorsal surface of tail.

16.
Sci Total Environ ; 933: 173080, 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38735320

RESUMO

In light of the pressing need to reduce carbon emissions, the biomass power generation industry has gained significant attention and has increasingly become a crucial focus in China. However, there are still considerable gaps in the historical background, status, and prospects of biomass power generation. Herein, the historical and current status of biomass power generation in China are systematically reviewed, with a particular emphasis on supportive policies, environmental impacts, and future projections. By 2022, the newly installed capacity for biomass power generation reached 3.34 MW with a total installed capacity of 41 MW. The power produced from biomass power generation is 182.4 billion kWh in China. The total installed capacity and generated power in 2022 were 1652 and 1139 folds higher than in 2006 when the first biomass generation plant was established. However, disparities in the distribution of biomass resources and power generation were observed. Key drivers of the industry development include tax, finance, and subsidy policies. Under the implementation of the 14th Five-Year Plan for renewable energy development and the goal of carbon neutrality, biomass power generation may achieve great success through more targeted policy support and advanced technologies that reduce air pollutant emissions. If combined with Bioenergy with Carbon Capture and Storage (BECCS) technology, biomass power generation will make its contribution to carbon neutrality in China.


Assuntos
Biomassa , China , Carbono/análise , Centrais Elétricas , Poluição do Ar/prevenção & controle , Poluição do Ar/estatística & dados numéricos , Poluentes Atmosféricos/análise , Energia Renovável
17.
Environ Int ; 186: 108641, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38621323

RESUMO

People generally spend most of their time indoors, making a comprehensive evaluation of air pollution characteristics in various indoor microenvironments of great significance for accurate exposure estimation. In this study, field measurements were conducted in Kunming City, Southwest China, using real-time PM2.5 sensors to characterize indoor PM2.5 in ten different microenvironments including three restaurants, four public places, and three household settings. Results showed that the daily average PM2.5 concentrations in restaurants, public spaces, and households were 78.4 ± 24.3, 20.1 ± 6.6, and 18.0 ± 4.3 µg/m3, respectively. The highest levels of indoor PM2.5 in restaurants were owing to strong internal emissions from cooking activities. Dynamic changes showed that indoor PM2.5 levels increased during business time in restaurants and public places, and cooking time in residential kitchens. Compared with public places, restaurants generally exhibit more rapid increases in indoor PM2.5 due to cooking activities, which can elevate indoor PM2.5 to high levels (5.1 times higher than the baseline) in a short time. Furthermore, indoor PM2.5 in restaurants were dominated by internal emissions, while outdoor penetration contributed mostly to indoor PM2.5 in public places and household settings. Results from this study revealed large variations in indoor PM2.5 in different microenvironments, and suggested site-specific measures for indoor PM2.5 pollution alleviation.


Assuntos
Poluição do Ar em Ambientes Fechados , Cidades , Monitoramento Ambiental , Material Particulado , Humanos , Poluição do Ar em Ambientes Fechados/efeitos adversos , Poluição do Ar em Ambientes Fechados/análise , Poluição do Ar em Ambientes Fechados/prevenção & controle , Culinária , Habitação , Material Particulado/efeitos adversos , Material Particulado/análise , Material Particulado/química , Material Particulado/classificação , Restaurantes , Inquéritos e Questionários , Fatores de Tempo , Saúde da População Urbana/estatística & dados numéricos
18.
Animals (Basel) ; 14(3)2024 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-38338043

RESUMO

Guanidinoacetic acid (GAA) functions as a precursor for creatine synthesis in the animal body, and maintaining ample creatine reserves is essential for fostering rapid growth. This study aimed to explore the impact of GAA supplementation on growth performance, rumen fermentation, blood indices, nutrient digestion, and nitrogen metabolism in Angus steers through two experiments: a feeding experiment (Experiment 1) and a digestive metabolism experiment (Experiment 2). In Experiment 1, thirty-six Angus steers (485.64 ± 39.41 kg of BW) at 16 months of age were randomly assigned to three groups: control (CON), a conventional dose of GAA (CGAA, 0.8 g/kg), and a high dose of GAA (HGAA, 1.6 g/kg), each with twelve steers. The adaptation period lasted 14 days, and the test period was 130 days. Weighing occurred before morning feeding on days 0, 65, and 130, with rumen fluid and blood collected before morning feeding on day 130. Experiment 2 involved fifteen 18-month-old Angus steers (575.60 ± 7.78 kg of BW) randomly assigned to the same three groups as in Experiment 1, with a 7-day adaptation period and a 3-day test period. Fecal and urine samples were collected from all steers during this period. Results showed a significantly higher average daily gain (ADG) in the CGAA and HGAA groups compared to the CON group (p = 0.043). Additionally, the feed conversion efficiency (FCE) was significantly higher in the CGAA and HGAA groups than in the CON group (p = 0.018). The concentrations of acetate and the acetate:propionate ratio were significantly lower in the CGAA and HGAA groups, while propionate concentration was significantly higher (p < 0.01). Serum concentration of urea (UREA), blood ammonia (BA), GAA, creatine, and catalase (CAT) in the CGAA and HGAA groups were significantly higher than in the CON group, whereas malondialdehyde (MDA) concentrations were significantly lower (p < 0.05). Digestibility of dry matter (DM) and crude protein (CP) and the nitrogen retention ratio were significantly higher in the CGAA and HGAA groups than in the CON group (p < 0.05). In conclusion, dietary addition of both 0.8 g/kg and 1.6 g/kg of GAA increased growth performance, regulated rumen fermentation and blood indices, and improved digestibility and nitrogen metabolism in Angus steers. However, higher doses of GAA did not demonstrate a linear stacking effect.

19.
Adv Mater ; : e2402324, 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38696823

RESUMO

Rechargeable all-solid-state lithium metal batteries (ASSLMBs) utilizing inorganic solid-state electrolytes (SSEs) are promising for electric vehicles and large-scale grid energy storage. However, the Li dendrite growth in SSEs still constrains the practical utility of ASSLMBs. To achieve a high dendrite-suppression capability, SSEs must be chemically stable with Li, possess fast Li transfer kinetics, and exhibit high interface energy. Herein, a class of low-cost, eco-friendly, and sustainable oxyhalide-nitride solid electrolytes (ONSEs), denoted as LixNyIz-qLiOH (where x = 3y + z, 0 ≤ q ≤ 0.75), is designed to fulfill all the requirements. As-prepared ONSEs demonstrate chemically stable against Li and high interface energy (>43.08 meV Å-2), effectively restraining Li dendrite growth and the self-degradation at electrode interfaces. Furthermore, improved thermodynamic oxidation stability of ONSEs (>3 V vs Li+/Li, 0.45 V for pure Li3N), arising from the increased ionicity of Li─N bonds, contributes to the stability in ASSLMBs. As a proof-of-concept, the optimized ONSEs possess high ionic conductivity of 0.52 mS cm-1 and achieve long-term cycling of Li||Li symmetric cell for over 500 h. When coupled with the Li3InCl6 SSE for high-voltage cathodes, the bilayer oxyhalide-nitride/Li3InCl6 electrolyte imparts 90% capacity retention over 500 cycles for Li||1 mAh cm-2 LiCoO2 cells.

20.
Appl Opt ; 52(11): 2312-9, 2013 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-23670760

RESUMO

We have designed a single thin planar diffractive optical element (DOE) based on the principle of diffractive optics to simultaneously split and concentrate the incident light into several energy ranges for lateral multijunction solar cells. A prototype with the maximum thickness of 6.95 µm and 32 quantized levels in depth was fabricated by photolithographic technology. The spectrum-splitting and concentrating performance of the prototype, which were measured quantitatively, show good agreement with the simulation results. As mass production of a DOE can be produced by imprint technology, our design provides a feasible means for low-cost, large-scale, and high-efficiency photovoltaic applications.

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