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1.
ACS Nano ; 18(26): 17339-17348, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38905021

RESUMO

In recent years, two-dimensional (2D) transition metal dichalcogenides (TMDCs) have been widely recognized as an ideal platform for surface-enhanced Raman scattering (SERS). Given their rich structural phases, phase transformation in 2D TMDCs is an efficient strategy to tailor their SERS performance. In this paper, we present the great SERS performance of multilayer 2M-WS2 and then investigate the effect of its phase transformation on SERS performance. It is observed that multilayer 2M-WS2 nanosheets undergo a thermally induced single-crystal phase transition from 2M-WS2 to 2H-WS2 upon thermal annealing or laser treatment. Distinguishing from the commercially available pure 2H-WS2 (P-2H-WS2), 2H-WS2 obtained by annealing and laser treatment still retain SERS properties comparable to those of 2M-WS2, among which the detection limits for CV molecules (10-8 M) are 3 orders of magnitude lower than that of P-2H-WS2 and the Raman intensity enhancements are ∼10-37 times higher. In contrast to the charge transfer (CT) mechanism governed by the Fermi level in metallic-phase 2M-WS2, 2H-WS2 obtained by phase transition exhibits accelerated CT facilitated by the bandgap reduction and reorganization resulting from the abundance of vacancies. This study introduces an interesting perspective and potential avenue for enhancing SERS through metal-to-semiconductor phase transitions in 2D TMDCs materials.

2.
Chaos ; 34(6)2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38829789

RESUMO

This paper reports an important conclusion that self-diffusion is not a necessary condition for inducing Turing patterns, while taxis could establish complex pattern phenomena. We investigate pattern formation in a zooplankton-phytoplankton model incorporating phytoplankton-taxis, where phytoplankton-taxis describes the zooplankton that tends to move toward the high-densities region of the phytoplankton population. By using the phytoplankton-taxis sensitivity coefficient as the Turing instability threshold, one shows that the model exhibits Turing instability only when repulsive phytoplankton-taxis is added into the system, while the attractive-type phytoplankton-taxis cannot induce Turing instability of the system. In addition, the system does not exhibit Turing instability when the phytoplankton-taxis disappears. Numerically, we display the complex patterns in 1D, 2D domains and on spherical and zebra surfaces, respectively. In summary, our results indicate that the phytoplankton-taxis plays a pivotal role in giving rise to the Turing pattern formation of the model. Additionally, these theoretical and numerical results contribute to our understanding of the complex interaction dynamics between zooplankton and phytoplankton populations.


Assuntos
Modelos Biológicos , Fitoplâncton , Zooplâncton , Animais , Zooplâncton/fisiologia , Fitoplâncton/fisiologia , Simulação por Computador , Dinâmica não Linear , Ecossistema , Plâncton/fisiologia , Dinâmica Populacional
3.
Chem Sci ; 15(21): 8204-8215, 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38817556

RESUMO

Electrocatalytic nitrate (NO3-) reduction reaction (eNO3-RR) to ammonia under ambient conditions is deemed a sustainable route for wastewater treatment and a promising alternative to the Haber-Bosch process. However, there is still a lack of efficient electrocatalysts to achieve high NH3 production performance at wastewater-relevant low NO3- concentrations. Herein, we report a Pd74Ru26 bimetallic nanocrystal (NC) electrocatalyst capable of exhibiting an average NH3 FE of ∼100% over a wide potential window from 0.1 to -0.3 V (vs. reversible hydrogen electrode, RHE) at a low NO3- concentration of 32.3 mM. The average NH3 yield rate at -0.3 V can reach 16.20 mg h-1 cm-2. Meanwhile, Pd74Ru26 also demonstrates excellent electrocatalytic stability for over 110 h. Experimental investigations and density functional theory (DFT) calculations suggest that the electronic structure modulation between Pd and Ru favors the optimization of NO3- transport with respect to single components. Along the *NO3 reduction pathway, the synergy between Pd and Ru can also lower the energy barrier of the rate-determining steps (RDSs) on Ru and Pd, which are the protonation of *NO2 and *NO, respectively. Finally, this unique alloying design achieves a high-level dynamic equilibrium of adsorption and coupling between *H and various nitrogen intermediates during eNO3-RR.

4.
Sci Rep ; 14(1): 12379, 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38811664

RESUMO

Although the issue of embodied pollutants in China's supply chains has garnered increasing attention, the dynamic changes occurring within them are unclear. Several existing studies analyze one-year or short-term data in supply chain. China's overall CH4 emissions have risen from 41.1 Tg in 2000 to 60 Tg in 2020, so conducting long-term analyses can yield a deeper understanding of the dynamic changes across the entire supply chain from production to consumption. This study uses the environmentally extended input-output analysis (EEIOA) and structural path analysis (SPA) methods to investigate the dynamic variation of China's embodied CH4 emissions in 20 industry sectors from 2000 to 2020, aiming to determine the key supply chain and key sectors. The results reveal that from the final demand perspective, consumption, investment and export drove 52.1%, 32%, and 15.9% of embodied CH4 emissions in 2020. The sector with the highest embodied CH4 emissions has changed from "Agriculture" in 2000 to "Construction" in 2010 to "Other service and activities" in 2020. The top listed supply chain path of embodied CH4 emissions has also evolved (starting from production to consumption) from "Agriculture → Rural consumption" in 2000 to "Agriculture → Food and tobacco → Urban consumption" in 2010 to "Agriculture → Urban consumption" in 2020. Notably, the high-ranked path, "Agriculture → Food and tobacco → Rural consumption", shows that the embodied CH4 emission flowing between agriculture and the food industry cannot be ignored. The supply chain path "Coal Mining → Nonmetal Mineral Products → Construction → Capital Formation" has risen from 17th in 2000 to 3rd in 2020. Thus, it is necessary to control CH4 emissions from sectors upstream, which are predominantly influenced by the construction industry, and a coordinated effort between sectors is also required to effectively reduce emissions. By 2020, the CH4 emissions driven by urban consumption were 3.1 times that of rural consumption. This study provides a comprehensive analysis of China's supply chain over the past two decades. In particular, it suggests policy interventions by controlling critical supply chain paths and key sectors associated with embodied CH4 emission, thereby facilitating the coordinated reduction of anthropogenic CH4 emissions.

5.
Environ Int ; 187: 108627, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38636273

RESUMO

BACKGROUND: Despite increased literature focusing on the role of the built environment (BE) in health, few cohort studies have quantitatively analyzed neighborhood walkability environment in relation to the risk of death and cardiovascular disease (CVD). This longitudinal study aimed at evaluating the association between perceived BE attributeswith mortality and major CVD based on the Prospective Urban Rural Epidemiology study in China (PURE-China). METHODS: The PURE-China study recruited 47,931 participants aged 35-70 years from 12 provinces of China between 2005 and 2009. The perceived BE information, including land use, street, aesthetics, and safety, was collected using the neighborhood environment walkability scale (NEWS) questionnaire, with higher scores indicating a more favorable rating. Two primary outcomes are all-cause mortality and major CVD event. The Cox frailty model with random intercepts was used to assess the association between the perceived total BE/subscales score and outcomes. RESULTS: Of 32,163 participants included in this study, 19,253 (59.9 %) were women, and the mean (SD) age was 51.0 (9.5) years. After a median follow-up period of 11.7 years (IQR 9.4 - 12.2), we observed that one standard deviation higher of combined BE scores was related to a lower risk of all-cause mortality (HR = 0.85; 95 %CI, 0.80-0.90), and major CVD events (HR = 0.95; 95 %CI, 0.90-0.99). The subscales of perceived BE were related to a lower risk, although a few were not significant. Land use mix-diversity and safety from crime were the two most significant subscales. Stronger risks were observed among urban and female participants. CONCLUSION: Favorable perceived BE characteristics were linked with a lower risk of all-cause mortality and major CVD events in Chinese population, especially in urban areas and females. Our findings can be used by policymakers to take action to mitigate the adverse effect of poor community conditions on health, such as improving local amenities and transport connectivity, providing building paths for walking, running and cycling.


Assuntos
Ambiente Construído , Doenças Cardiovasculares , Humanos , Doenças Cardiovasculares/mortalidade , Doenças Cardiovasculares/epidemiologia , Pessoa de Meia-Idade , Feminino , China/epidemiologia , Masculino , Adulto , Estudos Prospectivos , Idoso , Ambiente Construído/estatística & dados numéricos , Inquéritos e Questionários , População Rural/estatística & dados numéricos , Estudos Longitudinais , Características de Residência/estatística & dados numéricos , Caminhada
6.
Sci Total Environ ; 923: 171406, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38432361

RESUMO

Global climate change has significantly impacted the production of various crops, particularly long-term fruit-bearing plants such as citrus. This study analyzed the fruit quality of 12 citrus orchards (Citrus Sinensis L.Osbeck cv. Bingtang) in a subtropical region in Yunnan, China from 2014 to 2022. The results indicated that high rainfall (>220 mm) and low cumulative temperature (<3150 °C) promoted increases in titratable acidity (>1.8 %) in young fruits. As the fruits further expanded (with a horizontal diameter increasing from 50 to 65 mm), excessive rainfall (300-400 mm), lower cumulative temperature (<2400 °C), and a reduced diurnal temperature range (<10 °C) hindered decreases in titratable acidity. Conversely, low rainfall (<220 mm), high cumulative temperature (>3150 °C), and a high diurnal temperature range (>14 °C) promoted the accumulation of soluble solids in young fruits (9 %) at 120 days after flowering (DAF). Furthermore, low rainfall (<100 mm) favored the accumulation of soluble solids (1.5 %) during fruit expansion (195-225DAF). To quantify the relationship between fruit acidity and climate variables at 120 DAF, we developed a regression model, which was further validated by actual measurements and accurately predicted fruit acidity in 2023. Our findings have the potential to assist citrus growers in optimizing cultivation techniques for the production of high-quality citrus under increasingly variable climatic conditions.


Assuntos
Citrus sinensis , Citrus , Mudança Climática , China , Temperatura Baixa , Frutas
7.
Phys Rev E ; 109(1-1): 014217, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38366501

RESUMO

In this paper, sufficient conditions of Turing instability are established for general delayed reaction-diffusion-chemotaxis models with no-flux boundary conditions. In particular, we address the difficulty brought about by the time delay in investigating the Turing instability. These models involve the time delay parameter τ and the general density (concentration) function in chemotaxis terms with the chemotaxis parameter χ. Theoretical results reveal that the time delay parameter τ could determine the stability of positive equilibrium for ordinary differential equations, while the chemotaxis parameter χ could describe the stability of positive equilibrium for partial differential equations. In this fashion, the general conditions of Turing instability are presented. To confirm their validity, the delayed chemotaxis-type predator-prey model and the phytoplankton-zooplankton model are considered. It is found that these two models admit Turing instability, and the numerical results are in good agreement with the theoretical analysis. The obtained results are helpful in the application of the Turing pattern in models with time delay and chemotaxis.

8.
Small ; 20(23): e2309371, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38169101

RESUMO

Construction of heterojunctions is an effective strategy to enhanced electrocatalytic oxygen evolution reaction (OER), but the structural evolution of the active phases and synergistic mechanism still lack in-depth understanding. Here, an FeOOH/Ni3S2 heterostructure supported on nickel foam (NF) through a two-step hydrothermal-chemical etching method is reported. In situ Raman spectroscopy study of the surface reconstruction behaviors of FeOOH/Ni3S2/NF indicates that Ni3S2 can be rapidly converted to NiOOH, accompanied by the phase transition from α-FeOOH to ß-FeOOH during the OER process. Importantly, a deep analysis of Ni─O bond reveals that the phase transition of FeOOH can regulate the lattice disorder of NiOOH for improved catalytic activity. Density functional theory (DFT) calculations further confirm that NiOOH/FeOOH heterostructure possess strengthened adsorption for O-containing intermediates, as well as lower energy barrier toward the OER. As a result, FeOOH/Ni3S2/NF exhibits promising OER activity and stability in alkaline conditions, requiring an overpotential of 268 mV @ 100 mA cm-2 and long-term stability over 200 h at a current density of 200 mA cm-2. This work provides a new perspective for understanding the synergistic mechanism of heterogeneous electrocatalysts during the OER process.

9.
Small ; 20(9): e2307506, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37857574

RESUMO

Main group element-based materials are emerging catalysts for ammonia (NH3 ) production via a sustainable electrochemical nitrogen reduction reaction (N2 RR) pathway under ambient conditions. However, their N2 RR performances are less explored due to the limited active behavior and unclear mechanism. Here, an aluminum-based defective metal-organic framework (MOF), aluminum-fumarate (Al-Fum), is investigated. As a proof of concept, the pristine Al-Fum MOF is synthesized by the solvothermal reaction process, and the defect engineering method namely solvent-assisted linker exchange, is applied to create the defective Al sites. The defective Al sites play an important role in ensuring the N2 RR activity for defective Al-Fum. It is found that only the defective Al-Fum enables stable and effective electrochemical N2 RR, in terms of the highest production rate of 53.9 µg(NH3 ) h-1 mgcat -1 (in 0.4 m K2 SO4 ) and the Faradaic efficiency of 73.8% (in 0.1 m K2 SO4 ) at -0.15 V vs reversible hydrogen electrode) under ambient conditions. Density functional theory calculations confirm that the N2 activation can be achieved on the defective Al sites. Such sites also allow the subsequent protonation process via the alternating associative mechanism. This defect characteristic gives the main group Al-based MOFs the ability to serve as promising electrocatalysts for N2 RR and other attractive applications.

10.
Int J Phytoremediation ; 26(3): 382-392, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37578385

RESUMO

Based on the growth-promoting effect of plant growth promoting bacteria on plants and the mobilization of Cd by citric acid, an experiment was designed in which the combined treatment of Bacillus megaterium and citric acid promoted ryegrass to repair Cd-contaminated soil. This study aimed to evaluate the effects of different treatments on the antioxidant enzyme activity, photosynthesis intensity, Cd accumulation, and rhizosphere cadmium migration under cadmium contamination conditions. And the soil morphology and structure changes were studied by infrared spectroscopy FourierTransformInfrared(FT-IR) and scanning electron microscope Energy Dispersive Spectrometer(SEM-EDS) before and after different treatments. The results show that the combined treatment of Bacillus megaterium and citric acid significantly improved the oxidative stress defense and plant photosynthesis and increased of rye biomass. rye biomass 1.28 times higher than CK treatment. Joint treatment significantly increased the amount of shoot accumulation of Cd, 2.31 times higher than CK treatment, increased the migration and accumulation of cadmium. FTIR and SEM-EDS also showed that the organic constituents such as O-H, C-O and C-N in soils as a major mechanism for mobilization of the heavy metal Cd. Thus, the combined treatment of Bacillus megaterium and citric acid can promote plant growth, improve the damage to ryegrass caused by single organic acid addition, and improve the plant extraction efficiency, which is a feasible way to repair Cd-contaminated soil through activated extraction system.


The novelty of this study is the combined application of bacteria and chelating agents to ryegrass to improve phytoremediation efficiency. Bacillus giganosus has a good role in promoting the growth of ryegrass. As citrate, a small molecule chelate, can activate heavy metal cadmium and detoxify heavy metals, so it was selected. This study revealed in detail the response of ryegrass to the heavy metal Cd after exogenous addition of Bacillus gigansus and citrate, which is important for the application of cadmium removal by phytoremediation.


Assuntos
Lolium , Metais Pesados , Poluentes do Solo , Cádmio/metabolismo , Biodegradação Ambiental , Lolium/metabolismo , Ácido Cítrico/farmacologia , Espectroscopia de Infravermelho com Transformada de Fourier , Poluentes do Solo/metabolismo , Metais Pesados/análise , Solo/química , Bactérias/metabolismo
11.
Angew Chem Int Ed Engl ; 63(11): e202319685, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38151975

RESUMO

Glycerol is a byproduct of biodiesel production. Selective photoelectrochemical oxidation of glycerol to high value-added chemicals offers an economical and sustainable approach to transform renewable feedstock as well as store green energy at the same time. In this work, we synthesized monoclinic WO3 nanosheets with exposed (002) facets, which could selectively oxidize glycerol to glyceric acid (GLYA) with a photocurrent density of 1.7 mA cm-2 , a 73 % GLYA selectivity and a 39 % GLYA Faradaic efficiency at 0.9 V vs. reversible hydrogen electrode (RHE) under AM 1.5G illumination (100 mW cm-2 ). Compared to (200) facets exposed WO3 , a combination of experiments and theoretical calculations indicates that the superior performance of selective glycerol oxidation mainly originates from the better charge separation and prolonged carrier lifetime resulted from the plenty of surface trapping states, lower energy barrier of the glycerol-to-GLYA reaction pathway, more abundant active sites and stronger oxidative ability of photogenerated holes on the (002) facets exposed WO3 . Our findings show great potential to significantly contribute to the sustainable and environmentally friendly chemical processes via designing high performance photoelectrochemical cell via facet engineering for renewable feedstock transformation.

12.
ACS Nano ; 17(23): 23637-23648, 2023 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-37979042

RESUMO

Electrocatalytic nitrate (NO3-)/nitrite (NO2-) reduction reaction (eNOx-RR) to ammonia under ambient conditions presents a green and promising alternative to the Haber-Bosch process. Practically available NOx- sources, such as wastewater or plasma-enabled nitrogen oxidation reaction (p-NOR), typically have low NOx- concentrations. Hence, electrocatalyst engineering is important for practical eNOx-RR to obtain both high NH3 Faradaic efficiency (FE) and high yield rate. Herein, we designed balanced NOx- and proton adsorption by properly introducing Cu sites into the Fe/Fe2O3 electrocatalyst. During the eNOx-RR process, the H adsorption is balanced, and the good NOx- affinity is maintained. As a consequence, the designed Cu-Fe/Fe2O3 catalyst exhibits promising performance, with an average NH3 FE of ∼98% and an average NH3 yield rate of 15.66 mg h-1 cm-2 under the low NO3- concentration (32.3 mM) of typical industrial wastewater at an applied potential of -0.6 V versus reversible hydrogen electrode (RHE). With low-power direct current p-NOR generated NOx- (23.5 mM) in KOH electrolyte, the Cu-Fe/Fe2O3 catalyst achieves an FE of ∼99% and a yield rate of 15.1 mg h-1 cm-2 for NH3 production at -0.5 V (vs RHE). The performance achieved in this study exceeds industrialization targets for NH3 production by exploiting two available low-concentration NOx- sources.

13.
Langmuir ; 39(34): 11946-11953, 2023 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-37590920

RESUMO

Two-dimensional (2D) transition-metal dichalcogenides (TMDs) have emerged as promising materials for surface-enhanced Raman scattering (SERS) due to their unique electronic, optical, and mechanical properties. In this Perspective, we briefly introduce the fundamental properties, crystal-phase configurations, and phase transition strategies of TMDs materials. We then discuss the importance of the crystal phase in determining the SERS effect of TMDs, highlighting recent advances in phase-engineering approaches to affording remarkable SERS performance. By considering the current challenges and future directions for improving the crystal-phase engineering of TMDs in SERS, we also offer new insights into the design and synthesis of more promising TMD-based SERS substrates.

14.
Small ; 19(45): e2303654, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37415518

RESUMO

Laser-driven phase transition of 2D transition metal dichalcogenides has attracted much attention due to its high flexibility and rapidity. However, there are some limitations during the laser irradiation process, especially the unsatisfied surface ablation, the inability of nanoscale phase patterning, and the unexploited physical properties of new phase. In this work, the well-controlled femtosecond (fs) laser-driven transformation from the metallic 2M-WS2 to the semiconducting 2H-WS2 is reported, which is confirmed to be a single-crystal to single-crystal transition without layer thinning or obvious ablation. Moreover, a highly ordered 2H/2M nano-periodic phase transition with a resolution of ≈435 nm is achieved, breaking through the existing size bottleneck of laser-driven phase transition, which is attributed to the selective deposition of plasmon energy induced by fs laser. It is also demonstrated that the achieved 2H-WS2 after laser irradiation contains rich sulfur vacancies, which exhibits highly competitive ammonia gas sensing performance, with a detection limit below 0.1 ppm and a fast response/recovery time of 43/67 s at room temperature. This study provides a new strategy for the preparation of the phase-selective transition homojunction and high-performance applications in electronics.

15.
Ecotoxicol Environ Saf ; 255: 114766, 2023 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-36924559

RESUMO

With the increase in cadmium (Cd) release into the environment, it is necessary to find appropriate solutions to reduce soil Cd pollution. Microorganisms are a green and effective means for the remediation of Cd-contaminated soil. In this study, in a Cd-contaminated farmland, we screened and identified novel Cd-resistant strains, Paenarthrobactor nitroguajacolicus, Lysinibacillus fusiformis, Bacillus licheniformis, and Methyllobacium brachiatum, with minimum inhibitory concentrations of 100, 100, 50, and 50 mg/L, respectively, and added them each to pots containing Cd-contaminated rape plants to explore their remediation ability. The results showed that treatment with each of the four strains significantly increased the abundance of Nitrospirae, Firmicutes, Verrucomicrobia, and Patescibacterium in the rhizosphere soil of the plants. This led to changes in soil physical and chemical indices; pH; and available phosphorus, urease, and catalase activities, which were significantly negatively correlated with bioavailable Cd, reducing 28.74-58.82 % Cd enrichment to plants and 23.72-43.79 % Cd transport within plants, and reducing 5.52-10.68 % available cadmium in soil, effectively reducing the biotoxicity of Cd. Thus, this study suggests microbial remediation as a reliable option, forming a basis for the remediation of Cd-contaminated soil.


Assuntos
Cádmio , Poluentes do Solo , Cádmio/análise , Biodegradação Ambiental , Poluentes do Solo/análise , Bactérias , Solo/química
16.
Scand J Gastroenterol ; 58(8): 908-914, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36799202

RESUMO

BACKGROUND: Studies on aspirin's effects on metabolic-associated fatty liver disease (MAFLD) are limited. The aim of this study was to assess the association between aspirin and all-cause and cardiovascular disease (CVD) mortality in individuals with MAFLD. METHODS: Data were acquired from the National Health And Nutrition Examination Survey (NHANES) III. MAFLD diagnosis was consistent with that of international expert consensus. The independent association between aspirin and all-cause and CVD mortality in participants with MAFLD was evaluated by multiple Cox regression. Stratified analyses and interaction tests were performed to investigate whether covariates modified the association between aspirin and MAFLD mortality. RESULTS: Of 4594 eligible participants, 3,162 (68.83%) never took aspirin (0 times/month), 962 (20.94%) took it occasionally (1-14 times/month) and 470 (10.23%) took it regularly (≥15 times/month). Multiple cox regression showed that aspirin was not associated with overall mortality for MAFLD individuals. Stratified analysis revealed that in middle-aged (45-59 years) participants with MAFLD, occasional aspirin use was associated with low all-cause mortality risk (HR = 0.61, 95% CI = 0.43-0.86), while there was no significant association between aspirin and all-cause mortality among the young or the elderly. CONCLUSIONS: We found that the association between aspirin and all-cause MAFLD mortality varies by both age and frequency of administration. More prospective studies are needed to explore aspirin's influence on MALFD mortality.


Assuntos
Doenças Cardiovasculares , Hepatopatia Gordurosa não Alcoólica , Idoso , Pessoa de Meia-Idade , Humanos , Inquéritos Nutricionais , Aspirina/efeitos adversos , Hepatopatia Gordurosa não Alcoólica/complicações
17.
Sci Total Environ ; 863: 160969, 2023 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-36549539

RESUMO

Adsorption has been an important method for removing heavy metals from industrial wastewater. However, there has been a lack of an environmentally friendly, low-cost, biodegradable and easily recyclable material. China produces bones are not fully utilized leads to a waste of resources Therefore, efficient application of bone meal (BM) for remediation of contaminants in water would provide a promising alternative for resource utilization of bones. In this paper, we use a combination of BM and sodium alginate (SA) to prepare a novel BM/SA/calcium ion (BM/SA/Ca2+) double cross-linked composite hydrogel (BMSAH). Enhance the mechanical structure of SA while making the BM easy to recycle and reuse. The morphology and structure of the BMSAH were characterized using FT-IR spectroscopy and SEM-EDS. suggesting that the BMSAH can provide a larger specific surface area and high number of adsorption sites. The effects of the solution pH, ionic strength and contact time on the adsorption capacity of the BMSAH were investigated in depth, Under different conditions, BMSAH has a strong adsorption capacity of >90 %. XPS and FT-IR analysis showed that Cd2+ was adsorbed mainly via coordination interactions and hydrogen bonds with the carboxyl groups and nitrogen atoms in the BMSAH. A pseudo-second-order kinetic model, particle diffusion model and Isothermal adsorption lines indicate that the surface of the BMSAH is non-uniform suggesting that the adsorption of heavy metal ions by the BMSAH involves a combination of surface adsorption and intraparticle diffusion mechanisms, which is an overall chemical-physical adsorption process. In addition, the adsorption capacity of BMSAH remained above 90 % after three desorption cycles. Our work provides a new method for the preparation of a low-cost, high mechanical performance, biodegradable and easily recyclable physical hydrogels used for the removal of heavy metal ions.


Assuntos
Metais Pesados , Poluentes Químicos da Água , Cádmio/análise , Hidrogéis/química , Adsorção , Espectroscopia de Infravermelho com Transformada de Fourier , Alginatos/química , Poluentes Químicos da Água/análise , Metais Pesados/química , Água/química , Cinética , Concentração de Íons de Hidrogênio
18.
J Biosoc Sci ; 55(4): 708-734, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36120813

RESUMO

This study tracked the longstanding effect of childhood adversities on health status over the course of a life. This study used the data from China Health and Retirement Longitudinal Study which was a nationally representative survey and documented the generation who had arrived in the middle- and old-age phase and experienced the difficult time in the early founding of PR China in their childhood. Results shown the significant associations between multiple forms of children adversities (economic distress, child neglect, child abuse, lack of friends, parental mental health problems) and health status in adolescence (from 0.068 to 0.102, p<0.01), and health status in mid and late adulthood, including self-rated general health problems (from 0.039 to 0.061, p<0.01), chronic conditions (from 0.014 to 0.120, p<0.01 except for lack of friends), body aches (from 0.016 to 0.062, p<0.01 except for child neglect), and depression (from 0.047 to 0.112, p<0.01). Meanwhile, results also shown an underlying pathway (i.e., health status in adolescence) linking childhood adversities and health status in mid and late adulthood. Results suggested that the experience of multiple forms of adversities in childhood represented a substantial source of health risk throughout life.


Assuntos
Nível de Saúde , Longevidade , Adolescente , Humanos , Criança , Adulto , Estudos Longitudinais , Inquéritos e Questionários , China , Fatores de Risco
19.
Brain Sci ; 12(9)2022 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-36138938

RESUMO

(1) Introduction: Tourette syndrome (TS) and chronic tic disorder (CTD) are common neurodevelopmental/-psychiatric disorders. The aetiological factors that contribute to the pathogenesis of TS/CTD are still poorly understood. The possible risk factors for TS/CTD are considered to be a combination of genetic, immunological, psychological and environmental factors. A comprehensive systematic review was conducted to assess the association between aetiological factors and TS/CTD. (2) Methods: Electronic databases, including PubMed, Embase, Web of Science, Wanfang data, and CNKI, were searched to identify the etiological factors of children and adolescents (≤18 years) with TS/CTD based on a case-control study. Quality assessments were performed according to the Newcastle-Ottawa scale (NOS). (3) Results: According to sample sizes and NOS values, recent evidence may support that genetic factors (BTBD9 and AADAC), immunological factors (streptococcus and mycoplasma pneumoniae infections), environmental factors (conflict, history of perinatal diseases, and family history of neurological and psychiatric diseases and recurrent respiratory infections) and psychological factors (major life events) are associated with the pathogenesis of TS/CTD. (4) Conclusions: Some risk factors in different categories may be the etiological factors of TS/CTD, but there is a lack of studies on the interaction among the factors, which may require more attention in the future.

20.
Nano Lett ; 22(16): 6590-6598, 2022 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-35969868

RESUMO

Herein, with two-dimensional (2D) borocarbonitride (BCN) as a metal- and plasmon-free surface-enhanced Raman scattering (SERS) platform, we demonstrate a band structure engineering strategy to facilitate the charge transfer process for an enhanced SERS response. Especially, when the conduction band of the BCN substrate is tuned to align with the LUMO of the target molecule, remarkable SERS performance is achieved, ascribed to the borrowing effect from the vibronic coupling of resonances through the Herzberg-Teller coupling term. Meanwhile, fluorescence quenching is achieved due to the efficient charge transfer between the BCN substrate and target molecule. Consequently, BCN can accurately detect 20 kinds of trace chemical and bioactive analytes. Moreover, BCN exhibits excellent thermal and chemical stability, which can not only withstand high-temperature (300 °C) heating in the air but also resist long-term corrosion in harsh acid (pH = 0, HCl) and base (pH = 14, NaOH). This work provides new insight into band structure engineering in promoting the SERS performance of plasmon- and metal-free semiconductor substrates.


Assuntos
Metais , Análise Espectral Raman , Metais/química , Semicondutores , Análise Espectral Raman/métodos , Vibração
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