Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 25
Filtrar
1.
Angew Chem Int Ed Engl ; : e202409642, 2024 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-39037894

RESUMO

Aqueous zinc-ion batteries (ZIBs) hold immense promise for large-scale energy storage, but their practical application is hindered by zinc anode limitations. We introduce diethylenetriamine pentaacetate sodium salt (DTPA-Na) as a novel electrolyte additive to address these challenges. DTPA-Na's unique dual functionality enables the formation of robust, multi-layered solid electrolyte interphases (SEI) on the zinc anode and stable cathode electrolyte interphases (CEI) on the MnOOH cathode. This synergistic SEI/CEI engineering approach effectively suppresses interfacial side reactions, promotes uniform zinc deposition, and inhibits dendrite growth, leading to exceptional cycling stability and self-discharge inhibition. Asymmetrical cells employing DTPA-Na achieve an unprecedented 32,000 cycles at a high charging rate of 50 mA/cm2, while symmetric cells demonstrate a lifespan of 160 hours with 95% zinc utilization. Full Zn||MnOOH cells exhibit remarkable stability, maintaining 98.61% capacity retention after 720 hours of self-discharge and negligible capacity decay over 5000 cycles. Our work highlights the transformative potential of DTPA-Na as a dual-functional electrolyte additive, paving the way for high-performance ZIBs for practical energy storage applications.

2.
Sci Total Environ ; 937: 173475, 2024 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-38795985

RESUMO

Diniconazole is a chiral pesticide that exists in two enantiomers, R-(-)-diniconazole and S-(+)-diniconazole, with the R-enantiomer being much more active than the S-enantiomer. Previous enantioselective toxicology studies of diniconazole focused mostly on simple environmental model organisms. In this study, we evaluated the toxicokinetics of the two diniconazole enantiomers in rats and mice to provide a more comprehensive risk assessment. The two enantiomers displayed clear differences in their stereoselective contents in vivo. The t1/2 of R-(-)-diniconazole was 7.06 ± 3.35 h, whereas that of S-(+)-diniconazole was 9.14 ± 4.60 h, indicating that R-(-)-diniconazole was eliminated faster in vivo. The excretion rates of R-(-)-diniconazole and S-(+)-diniconazole were 4.08 ± 0.50 % and 2.68 ± 0.58 %, respectively, indicating more excretion of R-(-)-diniconazole. S-(+)-diniconazole had a higher bioavailability than R-(-)-diniconazole (52.19 % vs. 42.44 %). S-(+)-Diniconazole was also found in relatively high abundance in tissues such as the stomach, large intestine, small intestine, cecum, liver, kidney, brain, and testes, with the abundance being 1.71-2.48-fold that of R-(-)-diniconazole. The selective degradation of both enantiomers in the tissues and their mutual conversion in vivo were not observed, and this could indicate that configuration conversion did not contribute to the differences in the content of enantiomers in the tissues. Instead, such differences were mainly caused by the differences in affinity of each enantiomer for the tissues. Furthermore, investigation of the interconversion between optically pure R-(-)-diniconazole and S-(+)-diniconazole monomers in soil revealed no interconversion. All of the above results indicated no interconversion between R-(-)-diniconazole and S-(+)-diniconazole in vivo and in the soil, and that S-(+)-diniconazole tends to have a greater potential to accumulate in vivo. Thus, if only R-(-)-diniconazole is used as a pesticide, the negative impact on mammals and the environment will be reduced, suggesting that in agriculture, the application of optically pure R-(-)-diniconazole may be a better strategy.


Assuntos
Toxicocinética , Triazóis , Animais , Triazóis/toxicidade , Triazóis/química , Camundongos , Estereoisomerismo , Ratos , Masculino , Fungicidas Industriais/toxicidade , Fungicidas Industriais/química
3.
ACS Appl Mater Interfaces ; 16(15): 18812-18823, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38573821

RESUMO

When considered as a cathode candidate for aqueous Zn-ion batteries, V2O3 faces several problems, such as inherently unsuitable structure, fast structural degradation, and sluggish charge transport kinetics. In this paper, we report the synthesis of a V2O3 intimately coupled carbon aerogel by a controllable ion impregnation and solid-state reaction strategy using bacterial cellulose and ammonium metavanadate as raw materials. In this newly designed structure, the carbonized carbon fiber network provides fast ion and electron transport channels. More importantly, the cellulose aerogel functions as a dispersing and supporting skeleton to realize the particle size reduction, uniform distribution, and amorphous features of V2O3. These advantages work together to realize adequate electrochemical activation during the initial charging process and shorter transport distance and faster transport kinetics of Zn2+. The batteries based on the V2O3/CNF aerogel exhibit a high-rate performance and an excellent cycling stability. At a current density of 20 A g-1, the V2O3/CNF aerogel delivers a specific capacity of 159.8 mAh g-1, and it demonstrates an exceptionally long life span over 2000 cycles at 12 A g-1. Furthermore, the electrodes with active material loadings as high as 10 mg cm-2 still deliver appreciable specific capacities of 257 mAh g-1 at 0.1 A g-1.

4.
J Colloid Interface Sci ; 657: 931-941, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38096776

RESUMO

Zinc-ion batteries (ZIBs) are rapidly emerging as safe, cost-effective, nontoxic, and environmentally friendly energy storage systems. However, mildly acidic electrolytes with depleted protons cannot satisfy the huge demand for proton reactions in MnO2 electrodes and also cause several issues in ZIBs, such as rapidly decaying cycling stability and low reaction kinetics. Herein, we propose a pH-buffering strategy in which KH2PO4 is added to the electrolyte to overcome the problems caused by low proton concentrations. This strategy significantly improves the rate and cycle stability performance of zinc-manganese batteries, delivering a high capacity of 122.5 mAh/g at a high current density of 5 A/g and enabling 9000 cycles at this current density, with a remaining capacity of 70 mAh/g. Ex-situ X-ray diffraction and scanning electron microscopy analyses confirmed the generation/dissolution of Zn3PO4·4H2O and Zn4(OH)6(SO4)·5H2O, byproducts of buffer products and proton reactions. In-situ pH measurements and chemical titration revealed that the pH change during the electrochemical process can be adjusted to a low range of 2.2-2.8, and the phosphate distribution varies with the pH range. Those results reveal that H2PO4- provides protons to the cathode through the chemical balance of HPO42-, HPO42-, and Zn3PO4·4H2O. This study serves as a guide for studying the influences and mechanisms of buffering additives in Zn-MnO2 batteries.

5.
J Agric Food Chem ; 71(49): 19804-19816, 2023 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-38038649

RESUMO

Six new alkaloids (compounds 1-6) were isolated from Portulaca oleracea L. The compounds were triple pair (1 and 2, 3 and 4, and 5 and 6) enantiomers, with 1, 3, and 5 in the R-configuration and 2, 4, and 6 in the S-configuration, and all could bind to SUR1 according to molecular docking analysis. Treatment of STC-1 cells with each compound led to an influx of intracellular Ca2+, eventually leading to the secretion of glucagon-like peptide-1 (GLP-1), with compound 3 giving the highest secretion, resulting in 24.3 ± 7.03% more GLP-1 than nateglinide-treated cells, suggesting that these alkaloids may be able to reduce blood glucose based on their ability to stimulate the release of GLP-1. Furthermore, compound 3 also exhibited slightly faster absorption than nateglinide, as shown by pharmacokinetic analysis conducted in rats. Therefore, the results showed that some purslane alkaloids (such as compound 3) had good pharmacological activity in vivo and may have preventive and therapeutic effects on diabetes.


Assuntos
Alcaloides , Portulaca , Ratos , Animais , Portulaca/metabolismo , Nateglinida , Peptídeo 1 Semelhante ao Glucagon/metabolismo , Simulação de Acoplamento Molecular , Alcaloides/farmacologia , Alcaloides/análise
6.
J Agric Food Chem ; 70(38): 12180-12188, 2022 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-36121774

RESUMO

Oxathiapiprolin is a chiral fungicide, and it can affect the metabolism of the cholesterol compounds by inhibiting oxysterol binding protein (OSBP) to exert its fungicidal effect. The application of oxathiapiprolin in agriculture is widespread, and its residue in the environment is a threat to both human and animal health. The two oxathiapiprolin enantiomers differ in their fungicidal activity, biotoxicity, and degradation by environmental forces. However, their biotoxicity has not been reported in animals. The toxicokinetics of a pesticide should be a crucial component for the evaluation of its toxicity in vivo. In this study, we investigated the absorption, bioavailability, tissue distribution, and excretion of the two oxathiapiprolin enantiomers in rats to verify their toxicokinetic process in animals. An ultrahigh-performance liquid chromatography triple quadrupole tandem mass spectrometry (UHPLC-QQQ/MS) method was established to quantify the two oxathiapiprolin enantiomers in vivo. The two oxathiapiprolin enantiomers were found to have approximately the same absorption rate and bioavailability, and both were excreted mainly in the feces. The half-life of R-(-)-oxathiapiprolin was nearly twice that of S-(+)-oxathiapiprolin. R-(-)-oxathiapiprolin also had greater distribution than S-(+)-oxathiapiprolin in the liver, lungs, heart, spleen, kidneys, stomach, large intestine, small intestine, brain, and pancreas, supporting the notion that R-(-)-oxathiapiprolin could better bind with OSBP. The stereoselectivity of S-(+)-oxathiapiprolin in these tissues may be responsible for it being readily metabolized in vivo. The molecular docking technique was subsequently used to verify the more superior binding between R-(-)-oxathiapiprolin and OSBP compared with the binding between S-(+)-oxathiapiprolin and OSBP. The findings of this study could provide more reliable data for determining the toxicokinetics of a single enantiomer of oxathiapiprolin in animals, thereby providing some theoretical basis for its subsequent toxicological study.


Assuntos
Fungicidas Industriais , Praguicidas , Animais , Cromatografia Líquida de Alta Pressão/métodos , Fungicidas Industriais/química , Hidrocarbonetos Fluorados , Simulação de Acoplamento Molecular , Praguicidas/análise , Pirazóis , Ratos , Receptores de Esteroides , Estereoisomerismo , Toxicocinética
7.
Front Chem ; 10: 899810, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35572102

RESUMO

Aqueous zinc-ion batteries (ZIBs) are currently receiving widespread attention due to their merits of environmental-friendly properties, high safety, and low cost. However, the absence of stable zinc metal anodes severely restricts their potential applications. In this work, we demonstrate a simple oxygen plasma treatment method to modify the surface state of carbon cloth to construct an ideal substrate for zinc deposition to solve the dendrite growth problem of zinc anodes. The plasma treated carbon cloth (PTCC) electrode has lower nucleation overpotential and uniformly distributed C=O zincophilic nucleation sites, facilitating the uniform nucleation and subsequent homogeneous deposition of zinc. Benefiting from the superior properties of PTCC substrate, the enhanced zinc anodes demonstrate low voltage hysteresis (about 25 mV) and stable zinc plating/stripping behaviors (over 530 h lifespan) at 0.5 mA cm-2 with 15% depth of discharge (DOD). Besides, an extended cycling lifespan of 480 h can also be achieved at very high DOD of 60%. The potential application of the enhanced zinc anode is also confirmed in Zn|V10O24·12H2O full cell. The cells with Zn@PTCC electrode demonstrate remarkable rate capability and excellent cycling stability (95.0% capacity retention after 500 cycles).

8.
Food Funct ; 13(6): 3308-3317, 2022 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-35254360

RESUMO

In Asia, the flower of Hosta plantaginea (Lam.) Aschers (hosta flower) is both an edible food and medicine. The hosta flower is often used as a material for cooking porridge and scented tea and in combination with other plants for alleviating pharyngitis. To clarify the anti-pharyngitis effect of the hosta flower and evaluate its potential active ingredients, an ethanol extract of the hosta flower was prepared and partially purified via chromatography on a column packed with D101 macroporous resin, which was eluted with different concentrations of ethanol. The anti-pharyngitis effect of the crude extract and the various partially purified fractions was examined in an ammonia-induced acute pharyngitis rat model. The 30% ethanol-eluted fraction significantly alleviated the severity of pharyngitis in the rat, as evaluated by changes in the levels of cytokines (IL-1ß, IL-6, and TNF-α) and histological changes in the pharynx tissues. Subsequent HPLC-QTOF/MS (high-performance liquid chromatography coupled with quadrupole-time of flight tandem mass spectrometry) analysis of this fraction revealed kaempferol and its glycosides as the main components. Three of the main components were isolated and identified by 1D NMR. Their pharmacokinetics were studied for the first time by UHPLC-QQQ/MS (ultrahigh-performance liquid chromatography coupled with mass spectrometry). The findings suggested that the 30% ethanol-eluted fraction of the hosta flower extract may be a potential functional food for treating pharyngitis.


Assuntos
Flavonoides/uso terapêutico , Glicosídeos/uso terapêutico , Hosta/química , Faringite/tratamento farmacológico , Extratos Vegetais/uso terapêutico , Animais , Flavonoides/química , Flavonoides/isolamento & purificação , Flavonoides/farmacocinética , Flores/química , Glicosídeos/química , Glicosídeos/isolamento & purificação , Glicosídeos/farmacocinética , Masculino , Faringite/patologia , Fitoterapia , Extratos Vegetais/química , Ratos , Ratos Sprague-Dawley
9.
Sheng Wu Gong Cheng Xue Bao ; 38(3): 1248-1256, 2022 Mar 25.
Artigo em Chinês | MEDLINE | ID: mdl-35355490

RESUMO

Natural medicinal chemistry is one of the important courses for students in pharmacy majors. Its experimental teaching focuses on fostering comprehensive experimental skills and innovative abilities of undergraduates. Liaoning University has explored ways to promote the experimental teaching of natural drug chemistry based on the graduate employment and practical teaching experience in the past decade. These explorations include three aspects, such as synchronizing experimental teaching with theoretical teaching, fostering students' awareness of experimental safety, and improving experimental teaching methods in natural drug chemistry experiments. The practices showed that the reform has achieved a good effect. A teaching system that can achieve the three expected aspects has been established, which improved the teaching effect and quality of natural medicinal chemistry experimental courses for undergraduates. Furthermore, these explorations may facilitate fostering pharmacy specialists who can meet the opportunities of developing Chinese medicine and natural drug research and meet the requirements of employment.


Assuntos
Química Farmacêutica , Estudantes , Química Farmacêutica/educação , Humanos , Universidades
10.
Food Chem ; 357: 129759, 2021 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-33878587

RESUMO

Garcinia mangostana L. (mangosteen) is a tropical fruit that is rich in xanthones and is thought to have an anti-diabetic effect. In this study, we screened for the xanthones in mangosteen that could inhibit the activity of protein tyrosine phosphatase 1B (PTP1B), an enzyme that is targeted by diabetic drugs. Mice were orally administered mangosteen extract and blood samples were screened for the presence of PTP1B-interacting xanthones. Six such compounds (1-6) were identified by UF-HPLC-QTOF-MS and their inhibition against PTP1B was confirmed by activity assay. Among them, garcinone E (5) was found to be the most effective PTP1B inhibitor (IC50 = 0.43 µM). Tissue distribution analysis showed that the six compounds were distributed in eleven tissues, including the liver, muscle, fat, stomach, large intestine, small intestine, brain, kidney, heart, lung, and spleen. The results demonstrated that mangosteen might be a promising source of natural compounds with high PTP1B-inhibitory activity.

11.
Environ Sci Pollut Res Int ; 28(17): 21396-21410, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33411270

RESUMO

The bio-char was prepared by co-pyrolysis of municipal sewage sludge and biomass with chemical activation. The alkaline activating agents of KOH and K2CO3 were used to develop multilevel pore structure without heavy metal. The proximate analysis, ultimate analysis, SEM, and surface area and porosity analyzer were applied to present the physico-chemical properties and multilevel pore structure of bio-char. After impregnation pretreatment, the KOH provided more functional ingredients and reacted with C to expand pore structure for bio-chars. It was confirmed the specific surface area reached 2122.43 m2/g, and micropore area was 1674.85 m2/g after co-pyrolysis at 800 °C. Through the pretreatment of alkaline activation, the novel evaluation of heavy metal immobilization behavior in bio-char matrix were investigated by BCR sequential extraction and leaching tests. The KOH activation showed prominent immobilization behavior relatively, and the K2CO3 activation had more noticeable effects on leaching behavior. For Cu, Ni, Cr, Cd, Pb, and Zn, after co-pyrolysis at 900 °C, the proportion of unstable fraction decreased significantly, and the residual fractions of heavy metals were above 89.44% according to BCR sequential extraction procedure. Under optimal pyrolysis temperature, the Er value of bio-char reduced to 41.93, and the potential ecological risks decreased from considerable risk to low risk to ensure the further eco-friendly application.


Assuntos
Carvão Vegetal , Metais Pesados , Pirólise , Esgotos
12.
Comput Struct Biotechnol J ; 18: 3415-3424, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33294136

RESUMO

To cope with their continually fluctuating surroundings, pathovars of the unicellular phytopathogen Pseudomonas syringae have developed rapid and sophisticated signalling networks to sense extracellular stimuli, which allow them to adjust their cellular composition to survive and cause diseases in host plants. Comparative genomic analyses of P. syringae strains have identified various genes that encode several classes of signalling proteins, although how this bacterium directly perceives these environmental cues remains elusive. Recent work has revealed new mechanisms of a cluster of bacterial signal transduction systems that mainly include two-component systems (such as RhpRS, GacAS, CvsRS and AauRS), extracytoplasmic function sigma factors (such as HrpL and AlgU), nucleotide-based secondary messengers, methyl-accepting chemotaxis sensor proteins and several other intracellular surveillance systems. In this review, we compile a list of the signal transduction mechanisms that P. syringae uses to monitor and respond in a timely manner to intracellular and external conditions. Further understanding of these surveillance processes will provide new perspectives from which to combat P. syringae infections.

13.
J Agric Food Chem ; 68(43): 11975-11986, 2020 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-33054205

RESUMO

Garcinia mangostana L. (mangosteen) is a famous tropical fruit that contains a large number of xanthones. Regular consumption of mangosteen may confer health benefits and prevent some diseases, such as malaria. Quinone reductase 2 (QR-2) is a cytosolic enzyme found in human red blood cells, and it is becoming a target for chemoprevention because it is involved in the mechanisms of several diseases, including malaria. To understand whether the xanthones present in mangosteen might inhibit the activity of QR-2, blood samples were collected from rat following the oral administration of mangosteen extract and then incubated with QR-2 followed by UF-HPLC-QTOF/MS analysis to rapidly screen for and identify the QR-2-inhibiting xanthones. A total of 16 xanthones were identified, and six of these (α-mangostin, γ-mangostin, 8-deoxyartanin, 1,3,7-trihydroxy-2,8-di(3-methylbut-2-enyl)xanthone, garcinone E, and 9-hydroxycalabaxanthone) were subjected to QR-2 inhibition assay. γ-Mangostin exhibited the strongest inhibition, achieving an IC50 value of 3.82 ± 0.51 µM. Its interaction with QR-2 was found to involve hydrogen bond and arene-arene interaction as revealed by molecular docking. The present study could provide new insight into the potential application of mangosteen as functional food ingredients for inhibiting the activity of QR-2. However, the extent of daily intake of mangosteen required and the exact contribution of mangosteen to the prevention and treatment of malaria remain subjects of further study.


Assuntos
Inibidores Enzimáticos/farmacocinética , Garcinia mangostana/química , Extratos Vegetais/farmacocinética , Quinona Redutases/antagonistas & inibidores , Administração Oral , Animais , Cromatografia Líquida , Inibidores Enzimáticos/administração & dosagem , Inibidores Enzimáticos/química , Frutas/química , Humanos , Simulação de Acoplamento Molecular , Estrutura Molecular , Extratos Vegetais/administração & dosagem , Extratos Vegetais/química , Quinona Redutases/química , Quinona Redutases/metabolismo , Ratos , Ratos Sprague-Dawley , Espectrometria de Massas em Tandem , Xantonas/administração & dosagem , Xantonas/química , Xantonas/farmacocinética
14.
Oncol Lett ; 20(3): 2493-2498, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32782568

RESUMO

The present study aimed to evaluate the therapeutic effect of transcatheter arterial chemoembolization (TACE) combined with radioactive I-125 (iodine-125) seed implantation on liver cancer. A total of 38 liver cancer patients in the combined treatment group were treated with lobaplatin-TACE combined with radioactive I-125 seed implantation, while 45 patients in the TACE group were treated only with lobaplatin-TACE. Patients were followed up for survival time, and the liver function, change in α-fetoprotein (AFP) and side effects were evaluated. The average survival time of patients was 6.1 months in the TACE group and 8.2 months in the combined treatment group, and the overall survival was significantly different between the two groups (P<0.05). The response rate of lesions in the combined treatment group was superior to that observed in the TACE group, and the change in AFP in the TACE group was smaller than that in the combined treatment group. Improvement in the effects on most liver function indices in the combined treatment group were better than those in the TACE group. In addition, there were no differences in the side effects experienced between the two groups. Results of this study indicate that the effect of TACE combined with radioactive I-125 seed implantation is superior to that of TACE alone for the treatment of liver cancer, which can further benefit patients.

15.
Nanomicro Lett ; 12(1): 152, 2020 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-34138177

RESUMO

Rechargeable aqueous zinc-ion batteries (ZIBs) have been gaining increasing interest for large-scale energy storage applications due to their high safety, good rate capability, and low cost. However, the further development of ZIBs is impeded by two main challenges: Currently reported cathode materials usually suffer from rapid capacity fading or high toxicity, and meanwhile, unstable zinc stripping/plating on Zn anode seriously shortens the cycling life of ZIBs. In this paper, metal-organic framework (MOF) materials are proposed to simultaneously address these issues and realize high-performance ZIBs with Mn(BTC) MOF cathodes and ZIF-8-coated Zn (ZIF-8@Zn) anodes. Various MOF materials were synthesized, and Mn(BTC) MOF was found to exhibit the best Zn2+-storage ability with a capacity of 112 mAh g-1. Zn2+ storage mechanism of the Mn(BTC) was carefully studied. Besides, ZIF-8@Zn anodes were prepared by coating ZIF-8 MOF material on Zn foils. Unique porous structure of the ZIF-8 coating guided uniform Zn stripping/plating on the surface of Zn anodes. As a result, the ZIF-8@Zn anodes exhibited stable Zn stripping/plating behaviors, with 8 times longer cycle life than bare Zn foils. Based on the above, high-performance aqueous ZIBs were constructed using the Mn(BTC) cathodes and the ZIF-8@Zn anodes, which displayed an excellent long-cycling stability without obvious capacity fading after 900 charge/discharge cycles. This work provides a new opportunity for high-performance energy storage system.

16.
Sci Total Environ ; 702: 134593, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31726349

RESUMO

With the extensive applications and ongoing world demand, more and more amine surfactants are discharged into natural environment. However, the database about toxicity of amine surfactants is incomplete, which is not beneficial to environmental protection process. In this paper, the toxicity of 20 amine surfactants on Daphnia magna were tested to extend the toxicity data of amine surfactants. Besides, 35 molecular structure descriptors including quantum parameters, physicochemical parameters and topological indices were chosen and calculated as independent variables to develop the quantitative structure-activity relationship (QSAR) model between the toxicity of amine surfactants and their molecular structure by genetic function approximation (GFA) algorithm. According to statistical analysis, a robust model was built with the determination coefficient of (R2) was 0.962 and coefficient determinations of cross-validation (Rcv2) was 0.794. Meanwhile, external validation was implemented to evaluate the QSAR model. The result of coefficient determinations of cross-validation (Rext2) for external validation was calculated as 0.942, illustrating the model has great goodness-of-fit and good prediction ability.


Assuntos
Aminas/toxicidade , Tensoativos/toxicidade , Poluentes Químicos da Água/toxicidade , Estrutura Molecular , Relação Quantitativa Estrutura-Atividade
17.
Nanomicro Lett ; 11(1): 49, 2019 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-34138004

RESUMO

Aqueous rechargeable Zn/MnO2 zinc-ion batteries (ZIBs) are reviving recently due to their low cost, non-toxicity, and natural abundance. However, their energy storage mechanism remains controversial due to their complicated electrochemical reactions. Meanwhile, to achieve satisfactory cyclic stability and rate performance of the Zn/MnO2 ZIBs, Mn2+ is introduced in the electrolyte (e.g., ZnSO4 solution), which leads to more complicated reactions inside the ZIBs systems. Herein, based on comprehensive analysis methods including electrochemical analysis and Pourbaix diagram, we provide novel insights into the energy storage mechanism of Zn/MnO2 batteries in the presence of Mn2+. A complex series of electrochemical reactions with the co-participation of Zn2+, H+, Mn2+, SO42-, and OH- were revealed. During the first discharge process, co-insertion of Zn2+ and H+ promotes the transformation of MnO2 into ZnxMnO4, MnOOH, and Mn2O3, accompanying with increased electrolyte pH and the formation of ZnSO4·3Zn(OH)2·5H2O. During the subsequent charge process, ZnxMnO4, MnOOH, and Mn2O3 revert to α-MnO2 with the extraction of Zn2+ and H+, while ZnSO4·3Zn(OH)2·5H2O reacts with Mn2+ to form ZnMn3O7·3H2O. In the following charge/discharge processes, besides aforementioned electrochemical reactions, Zn2+ reversibly insert into/extract from α-MnO2, ZnxMnO4, and ZnMn3O7·3H2O hosts; ZnSO4·3Zn(OH)2·5H2O, Zn2Mn3O8, and ZnMn2O4 convert mutually with the participation of Mn2+. This work is believed to provide theoretical guidance for further research on high-performance ZIBs.

18.
Mil Med ; 183(3-4): e97-e106, 2018 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-29514345

RESUMO

Introduction: Forward surgical teams (FSTs) have been used as highly mobile surgical facilities that provide "damage control" medical support in modern wars. FST regiments differ greatly in different armed services and nations. We systemically reviewed the utilization of FSTs around the world with an emphasis on the medical conditions and workloads encountered by FSTs in modern wars. Materials and Methods: We searched for terms related to FSTs, such as "Forward Surgical Team" and "Field Surgical Team," in the PubMed, EMBASE, Web of Science, and MEDLINE databases and collected any articles that provided numerical data on the organization of medical personnel combat casualty characteristics, including the casualty composition, injury types and locations, and mechanisms of injury, and surgical procedures performed. Technical articles, case reports of specific types of injury or disease, and literature reviews of previous experiences and logistical theories were discarded. Results: We identified 24 articles involving 29 FSTs that were included in the analysis. The FSTs were typically composed of 8-20 medical personnel and had limited medical capacity. Battle-related injuries constituted approximately two-thirds of all injury types treated by the FSTs. The extremities, torso, and head and neck were the three most frequently injured sites and accounted for approximately 51.1%, 16.6%, and 13.2% of all wounds, respectively. The three most frequent injury mechanisms were fragments or explosive injuries (44.8%), gunshot wounds (28.1%), and motor vehicle accidents/road traffic accidents (9.1%). Soft tissue surgeries (41.0%) and orthopedic operations (31.6%) were the two procedures that were most frequently performed by the FSTs. The average numbers of surgical procedures performed by small FSTs (1.27/unit·day) and full FSTs (1.28/unit·day) seemed to be comparable. Conclusion: Modern conflict may require more flexible small FSTs, especially during the initial phases of war. More orthopedic surgeons should be included in FSTs, and orthopedic skill training should be intensified before deployment. The utilization of FSTs and level III facilities must be evaluated within the context of the battlefield conditions, medical care requirements, and evacuation efficiency.


Assuntos
Cirurgia Geral/métodos , Medicina Militar/métodos , Guerra/estatística & dados numéricos , Campanha Afegã de 2001- , Cirurgia Geral/estatística & dados numéricos , Humanos , Internacionalidade , Medicina Militar/estatística & dados numéricos , Estudos Retrospectivos , Revisão da Utilização de Recursos de Saúde
19.
PLoS One ; 12(9): e0184430, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28877267

RESUMO

There have been many terms used to describe the One Health concept, including movement, strategy, framework, agenda, approach, among others. However, the inter-relationships of the disciplines engaged in the One Health concept have not been well described. To identify and better elucidate the internal feedback mechanisms of One Health, we employed a system dynamics approach. First, a systematic literature review was conducted via searches in PubMed, Web of Knowledge, and ProQuest with the search terms: 'One Health' and (concept* or approach*). In addition, we used the HistCite® tool to add significant articles on One Health to the library. Then, of the 2368 articles identified, 19 were selected for evaluating the inter-relationships of disciplines engaged in One Health. Herein, we report a visually rich, theoretical model regarding interactions of various disciplines and complex problem descriptors engaged in One Health problem solving. This report provides a conceptual framework for future descriptions of the interdisciplinary engagements involved in One Health.


Assuntos
Saúde Global , Promoção da Saúde/métodos , Teoria de Sistemas , Comportamentos Relacionados com a Saúde , Humanos , Modelos Teóricos
20.
Chem Commun (Camb) ; 53(51): 6872-6874, 2017 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-28604865

RESUMO

Zn-ion batteries have been widely investigated due to their low cost, high safety and eco-friendliness. We comprehensively evaluate the performance of oxides (MoO3, TiO2, and Fe3O4), sulfides (MoS2, WS2, and MnS) and borides (TiB2 and ZrB2) in zinc ion battery systems. It is found that MnS is a good alternative cathode material with a reversible capacity of 221 mA h g-1, while the other materials show different behaviours.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...