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1.
J Food Sci ; 89(3): 1337-1346, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38258896

RESUMEN

To investigate the effect of hawthorn polyphenols on the physicochemical properties and digestibility of corn starch, different proportions (1%, 2%, 3%, and 4% [w/w]) of hawthorn polyphenol extracts (HPEs) were mixed with corn starch, and their physicochemical properties and digestive properties were characterized by X-ray diffraction, Fourier transform infrared spectroscopy, Rapid Visco Analysis, differential scanning calorimetry, and in vitro/in vivo analysis. Results indicated that small V-type crystal starch tended to be formed in the samples, and the addition of HPEs reduced the viscosity, prolonged the gelatinization temperature of corn starch, and increased the proportion of slowly digestible starch and resistant starch of the corn starch, which accounted for 36.32% ± 1.05% and 33.32% ± 4.07%, respectively. Compared with the raw corn starch, the postprandial blood glucose of mice that were administered the hawthorn polyphenols decreased significantly: the blood glucose peak (30 min) decreased from 14.30 ± 1.52 to 11.77 ± 1.21 mmol/L. Our study might provide some basic theoretical support for the application of hawthorn polyphenols in healthy starchy food processing.


Asunto(s)
Crataegus , Almidón , Animales , Ratones , Almidón/química , Zea mays , Polifenoles , Glucemia , Difracción de Rayos X , Viscosidad , Espectroscopía Infrarroja por Transformada de Fourier
2.
Int J Biol Macromol ; 260(Pt 1): 129525, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38237832

RESUMEN

Nano starch exhibits many advantages for application in diverse fields. Amaranth starch consisted of starch particle aggregates, isolated amaranth starch, and few natural nano starch (NNS), while NNS (0.92 ± 0.12 µm) was successfully isolated for the first time. Compared with the isolated amaranth starch, NNS showed smaller particle size but larger molecular weight, suggesting that the molecules arranged densely. NNS had a weak A-type crystal structure because of its more content of short starch chains, but higher amylose content resulted in the increase of its gelatinization temperature. The special NNS, owning several different physicochemical properties from amaranth starch, can open new ways for the production and application of nano biomass materials.


Asunto(s)
Amaranthus , Almidón , Almidón/química , Amilosa/química , Tamaño de la Partícula , Temperatura , Amaranthus/química
3.
Int J Biol Macromol ; 253(Pt 7): 127474, 2023 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-37858640

RESUMEN

The effects of ferulic acid (FA), protocatechuic acid (PA), and gallic acid (GA) on the physicochemical characteristics, structural properties, and in vitro digestion of gelatinized potato starch (PS) were investigated. Rapid viscosity analysis revealed that the gelatinized viscosity parameters of PS decreased after complexing with different phenolic acids. Dynamic rheology results showed that phenolic acids could reduce the values of G' and G″ of PS-phenolic acid complexes, demonstrating that the addition of phenolic acids weakened the viscoelasticity of starch gel. Fourier-transform infrared spectra and X-ray diffraction results elucidated that phenolic acids primarily reduced the degree of short-range ordered structure of starch through non-covalent interactions. The decrease in thermal stability and the more porous microstructure of the complexes confirmed that phenolic acids could interfere with the gel structure of the starch. The addition of different phenolic acids decreased the rapidly digestible starch (RDS) content and increased the resistant starch (RS) content, with GA exhibiting the best inhibitory capacity on starch in vitro digestibility, which might be associated with the number of hydroxy groups in phenolic acids. These results revealed that phenolic acids could affect the physicochemical characteristics of PS and regulate its digestion and might be a potential choice for producing slow digestibility starch foods.


Asunto(s)
Solanum tuberosum , Solanum tuberosum/química , Almidón/química , Difracción de Rayos X , Viscosidad , Ácido Gálico , Digestión
4.
Int J Biol Macromol ; 253(Pt 2): 126675, 2023 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-37660848

RESUMEN

Starch plays a pivotal role in food and other industries, necessitating the exploration of new starch sources to cater the substantial requirement. This study delved into the variations in the physicochemical properties, structure attributes and in vitro digestibility of seed starches extracted from five distinct loquat cultivars (Eriobotrya japonica L.). The starch extraction yield of loquat seeds was found to be 45.2 % as an average. Loquat seed starches were designated as having high-amylose starch (>50 %). The starch granules exhibited similar shapes, but granular size significantly varied across the cultivars. Loquat starches presented a C-type crystalline pattern with relative crystallinity from 17.14 % to 21.06 %. The short-range ordered structure of the starches differed with loquat cultivars. The swelling power, solubility and amylose leaching of loquat starches increased with increasing temperature, significantly varying among different cultivars. Gelatinization parameters exhibited significant variations among the loquat starches. Different loquat starches exhibited pronounced variations in paste clarity, water and oil absorption capacity. Marked differences were detected in proportions of rapidly digestible starch (RDS), slowly digestible starch (SDS), and resistant starch (RS) across the five cultivars, with RS being particularly prominent fraction with an average of 84.30 %. These compressive findings offer valuable insights into the potential application of loquat seed starches in the formulation of foods and various industrial products.


Asunto(s)
Amilosa , Eriobotrya , Amilosa/química , Almidón/química , Semillas , Almidón Resistente
5.
Int J Biol Macromol ; 248: 125912, 2023 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-37479207

RESUMEN

To investigate the effect of heat-moisture treatment (HMT) on the physiochemical properties and in vitro digestibility of corn starch, the pasting behavior, viscoelasticity, thermal properties, long/short range structure, morphology and in vitro digestion of corn starch treated with different HMT conditions (HMT-20, 25, 30, 35 and 40 %) were characterized. Results indicated that after HMT, the pasting and disintegration behaviors of corn starch were affected and correlated with the moisture content. The dynamic viscoelasticity of corn starch was changed, and when glassy conditions were reached, the elastic properties decreased with increasing moisture while the viscous properties increased, especially for the HMT-40 %. The thermal stability of starch was improved by HMT, although the enthalpy of pasting (ΔH) was reduced. Additionally, the HMT processing also promoted the conversion of RDS to SDS and/or RS (SDS and RS increased to 39.80 % and 31.68 % for HMT-40 %, respectively), which might attribute to the rearrangement of free starch molecules. The present work provides a potential approach to make functional starches with healthy properties.


Asunto(s)
Almidón , Zea mays , Almidón/química , Zea mays/química , Calor , Termodinámica , Digestión
6.
Molecules ; 28(9)2023 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-37175311

RESUMEN

Neohesperidin (NH), a natural flavonoid, exerts multiple actions, such as antioxidant, antiviral, antiallergic, vasoprotective, anticarcinogenic and anti-inflammatory effects, as well as inhibition of tumor progression. In this study, the NH-taro starch complex is prepared, and the effects of NH complexation on the physicochemical properties, structure and in vitro digestibility of taro starch (TS) are investigated. Results showed that NH complexation significantly affected starch gelatinization temperatures and reduced its enthalpy value (ΔH). The addition of NH increased the viscosity and thickening of taro starch, facilitating shearing and thinning. NH binds to TS via hydrogen bonds and promotes the formation of certain crystalline regions in taro starch. SEM images revealed that the surface of NH-TS complexes became looser with the increasing addition of NH. The digestibility results demonstrated that the increase in NH (from 0.1% to 1.1%, weight based on starch) could raise RS (resistant starch) from 21.66% to 27.75% and reduce RDS (rapidly digestible starch) from 33.51% to 26.76% in taro starch. Our work provided a theoretical reference for the NH-taro starch complex's modification of physicochemical properties and in vitro digestibility with potential in food and non-food applications.


Asunto(s)
Colocasia , Hesperidina , Almidón/química , Colocasia/química , Temperatura
7.
Parasitol Res ; 122(7): 1695-1699, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37199766

RESUMEN

Due to the increasing number of returnees from malaria endemic areas, imported malaria has become a public health challenge in China. To better understand the characteristics of imported Plasmodium species and adjust appropriate strategies for malaria prevention and control in Eastern China, we conducted molecular detection and species identification on 1282 imported malaria cases in Shandong Province between 2012 and 2018. The findings showed that P. falciparum was predominant, particularly in cases imported from Africa. P. vivax was the dominant species imported from Asian countries. Additionally, imported P. ovale and P. malariae emerged in the province. Further surveillance and control of imported malaria among returnees from Africa and Southeast Asia is needed to be strengthened in Eastern China.


Asunto(s)
Malaria Falciparum , Malaria Vivax , Malaria , Plasmodium , Humanos , Malaria/diagnóstico , Malaria/epidemiología , Malaria/prevención & control , Plasmodium/genética , África , China/epidemiología
8.
Infect Dis Poverty ; 12(1): 54, 2023 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-37217956

RESUMEN

BACKGROUND: Soil-transmitted helminths (STHs) were previously endemic in Shandong Province, China. This study aimed to analyze the STHs prevalence trend and the natural, social, and human cognitive and behavioural factors influencing the discrepancies between high and low infection levels from 2016 to 2020 in Shandong Province in eastern China. METHODS: STHs surveillance data of Shandong Province from 2016 to 2020 were obtained from China Information Management System for Prevention and Control of Parasitic Diseases. STHs infections were detected by modified Kato-Katz method. Comprehensive information on the natural and social factors, STHs-related knowledge and behaviours were collected through questionnaire surveys. Retrospective spatial scan analysis was performed using SaTScan v10.1 to evaluate any identified spatial clusters of STHs infection for statistical significance and Bayes discriminant analysis was used to discriminate the high or low infection groups of the villages. RESULTS: In total, 72,160 participants were involved in our survey from 2016 to 2020. The overall STHs prevalence rate was 1.13%, with the eastern region of Shandong Province having the highest rate (2.02%). The predominant species was T. trichiura, with the prevalence rate of 0.99% and the ≥ 70-year age group possessed the highest rate of 2.21%. The STHs prevalence rate showed an annual linear downward trend from 2016 to 2020 ([Formula: see text] = 127.600, P < 0.001). Respondents aged ≥ 60 years had the lowest awareness level of STHs-related prevention knowledge (all P < 0.05), and were the most likely to adopt the practice of fertilizing with fresh stool (χ2 = 28.354, P < 0.001). Furthermore, the southern region demonstrated the highest temperature and rainfall level and the lowest GNP and annual net income per capita (all P < 0.05). CONCLUSIONS: There is a remarkable declining in STHs prevalence in Shandong Province from 2016 to 2020. However, the prevalence rates of STHs especially T. trichiura in the southern and eastern regions were still high, and the elderly were more susceptible to be infected with STHs owning to their low awareness level of STHS-related prevention knowledge and high adoption rate of dangerous production and living behaviours. Integrated approaches of health education, environment improvement and behaviour change should be strengthened to obtain a further reduction of STHs prevalence in China.


Asunto(s)
Helmintiasis , Helmintos , Anciano , Animales , Humanos , Suelo/parasitología , Prevalencia , Teorema de Bayes , Estudios Retrospectivos , Helmintiasis/epidemiología , China/epidemiología , Heces/parasitología
9.
J Colloid Interface Sci ; 635: 105-116, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36580693

RESUMEN

Tin based materials are widely investigated as a potential anode material for lithium-ion batteries. Effectively dispersing SnO2 nanocrystals in carbonaceous supporting skeleton using simplified methods is both promising and challenging. In this work, water soluble chitosan (CS) chains are employed to modulate the redox coprecipitation reaction between stannous chloride (SnCl2) and few-layered graphene oxide (GO), where the excessive restacking of the corresponding reduced graphene oxide sheets (RGO) has been effectively inhibited and the grain size of the in-situ formed SnO2 nanoparticles have been significantly controlled. In particular, the CS molecules are gradually detached from the RGO sheets with the GO deoxygenation process, leaving only a small quantity of CS remnants in the intermediate SnO2@CS@RGO sample. The final SnO2/CSC/RGO sample with significantly improved microstructure is synthesized after a simple thermal treatment, which delivers a high specific capacity of 842.9 mAh g-1 at 1000 mA·g-1 for 1000 cycles in half cells and a specific capacity of 410.5 mAh g-1 at 200 mA·g-1 for 100 cycles in full cells. The reasons for the good lithium-ion storage performances for the SnO2/CSC/RGO composite have been studied.

10.
Food Chem ; 402: 134502, 2023 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-36303392

RESUMEN

To investigate the multi-scale structural changes and digestibility of parboiled rice, the side chain distribution, helical structure, short/long-range ordered structure, and lamellar structure were systematically characterized and an in vivo postprandial blood glucose test was applied. The results indicate that parboiling has little effect on the side chain distribution, double helix content and helical structure order of parboiled rice. The crystal type of rice starch changed from type A to A + V or B + V after parboiling and the relative crystallinity decreased from 30.45 % to a minimum of 6.87 %. The in vivo study also indicated that parboiling significantly reduces the glycaemic index of rice to medium level. Our work is the first to focus on the parboiling conditions, multi-scale structural changes and in vivo digestibility of parboiled rice, which might provide guidance for the design of less digestible parboiled rice in the future.


Asunto(s)
Oryza , Oryza/química , Culinaria/métodos , Almidón/química , Glucemia , Digestión
11.
Food Chem ; 403: 134153, 2023 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-36358064

RESUMEN

Annealing treatment on the physicochemical properties and hydrolysis of maize, potato and pea starch were investigated in present study. Results indicated that annealing treatment did not change the morphology of the starch. However, the relative crystallinity of maize and potato starch showed a peak trend as the annealing time extended, while pea starch showed a lower relative crystallinity. Besides, all the annealed starch showed a decrease in peak viscosity and an increase in pasting time. Little difference in the rapidly digestive starch (RDS) and resistant starch (RS) contents of annealed maize starch and pea starch were observed after annealing, while annealed potato starch (72 h) showed an increased RS content (23.37 ± 5.36 %) and a decreased RDS content (52.60 ± 6.14 %), respectively. The obtained results may provide a better understanding of the physicochemical properties and enzymatic hydrolysis of annealed starch with different semi crystalline type.


Asunto(s)
Solanum tuberosum , Almidón , Almidón/química , Hidrólisis , Solanum tuberosum/química , Viscosidad , Zea mays/química , Amilosa/química
12.
J Colloid Interface Sci ; 630(Pt B): 86-98, 2023 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-36327742

RESUMEN

Fe based metal organic framework (MOF) materials are being extensively investigated as a precursor sample for engineering carbon supported iron containing nanoparticles composites. Rational design and engineering Fe-containing MOFs with optimized structures using economic and eco-friendly methods is a challenging task. In this work, 1,3,5-benzenetricarboxylic acid (C9H6O6, trimesic acid, H3BTC) and metal Fe are employed to synthesize a MOF sample Fe-BTC in a mild hydrothermal condition. Moreover, with the addition of a small quantity of graphene oxide (GO) as dispersant, a redox coprecipitation reaction has taken place where small Fe-BTC domains well dispersed by reduced graphene oxide (RGO). The Fe-BTC/RGO intermediate sample is finally converted to the hierarchical Fe3O4@C/RGO composite, which delivers an ultrahigh specific capacity of 1262.61 mAh·g-1 at 200 mA·g-1 after 150 cycles and a superior reversible capacity of 910.65 mAh·g-1 at 1000 mA·g-1 after 300 cycles in half cells. The full cell performance for the Fe3O4@C/RGO composite have been studied. It is also revealed that the improved structural stability, high pseudocapacitive contribution and enhanced lithium-ion and electron transportation conditions jointly guarantee the outstanding lithium-ion storage performances for the Fe3O4@C/RGO composite over long-time cycling. The synthesized samples have good potential for wider application.

13.
Malar J ; 21(1): 369, 2022 Dec 04.
Artículo en Inglés | MEDLINE | ID: mdl-36464686

RESUMEN

BACKGROUND: Artemisinin-based combination therapy (ACT) has been recommended as the first-line treatment by the World Health Organization to treat uncomplicated Plasmodium falciparum malaria. However, the emergence and spread of P. falciparum resistant to artemisinins and their partner drugs is a significant risk for the global effort to reduce disease burden facing the world. Currently, dihydroartemisinin-piperaquine (DHA-PPQ) is the most common drug used to treat P. falciparum, but little evidence about the resistance status targeting DHA (ACT drug) and its partner drug (PPQ) has been reported in Shandong Province, China. METHODS: A retrospective study was conducted to explore the prevalence and spatial distribution of Pfk13 and Pfcrt polymorphisms (sites of 72-76, and 93-356) among imported P. falciparum isolates between years 2015-2019 in Shandong Province in eastern China. Individual epidemiological information was collected from a web-based reporting system were reviewed and analysed. RESULTS: A total of 425 P. falciparum blood samples in 2015-2019 were included and 7.3% (31/425) carried Pfk13 mutations. Out of the isolates that carried Pfk13 mutations, 54.8% (17/31) were nonsynonymous polymorphisms. The mutant alleles A578S, Q613H, C469C, and S549S in Pfk13 were the more frequently detected allele, the mutation rate was the same as 9.7% (3/31). Another allele Pfk13 C580Y, closely associated with artemisinin (ART) resistance, was found as 3.2% (2/31), which was found in Cambodia. A total of 14 mutant isolates were identified in Western Africa countries (45.2%, 14/31). For the Pfcrt gene, the mutation rate was 18.1% (77/425). T76T356 and T76 were more frequent in all 13 different haplotypes with 26.0% (20/77) and 23.4% (18/77). The CVIET and CVIKT mutant at loci 72-76 have exhibited a prevalence of 19.5% (15/77) and 3.9% (3/77), respectively. The CVIET was mainly observed in samples from Congo (26.7%, 4/15) and Mozambique (26.7%, 4/15). No mutations were found at loci 97, 101 and 145. For polymorphisms at locus 356, a total of 24 isolates were identified and mainly from Congo (29.2%, 7/24). CONCLUSION: These findings indicate a low prevalence of Pfk13 in the African isolates. However, the emergence and increase in the new alleles Pfcrt I356T, reveals a potential risk of drug pressure in PPQ among migrant workers returned from Africa. Therefore, continuous molecular surveillance of Pfcrt mutations and in vitro susceptibility tests related to PPQ are necessary.


Asunto(s)
Artemisininas , Malaria Falciparum , Humanos , Plasmodium falciparum/genética , Estudios Retrospectivos , Artemisininas/farmacología , Malaria Falciparum/epidemiología , China/epidemiología
14.
J Colloid Interface Sci ; 628(Pt B): 1-13, 2022 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-35973253

RESUMEN

A straightforward and eco-friendly method is demonstrated to engineer magnetite (Fe3O4) nanoparticles well dispersed by an amorphous amylose-derived carbon (AMC) and reduced graphene oxide (RGO) framework. Naturally available amylose (AM) serves as both reducing agent for few-layered graphene oxide (GO) in the first mild redox coprecipitation system and precursor for small-sized pyrolytic AMC in the following thermal treatment. In particular, the presence of the AM molecules effectively limits the crystal growth kinetics for the akaganeite (FeOOH) in the intermediate FeOOH@AM/RGO sample, which contributes to the transformation to Fe3O4 nanoparticles with significantly controlled size in the final Fe3O4@AMC/RGO composite. As a result, both Fe3O4 nanoparticles and AMC domains are adjacently anchored on the larger sized RGO sheets, and a unique hierarchical structure has been engineered in the Fe3O4@AMC/RGO sample. Compared with the controlled Fe3O4@RGO sample, the Fe3O4@AMC/RGO composite exhibits remarkably enhanced initial coulombic efficiency, superior cycling stability and rate performance for lithium-ion storage. The mechanisms of the interaction between GO sheets and AM molecules as well as the inspiring electrochemical behaviors of the Fe3O4@AMC/RGO electrode have been revealed. The Fe3O4@AMC/RGO sample possesses good potential for scaling-up and finding applications in wider fields.


Asunto(s)
Litio , Nanopartículas de Magnetita , Litio/química , Nanopartículas de Magnetita/química , Amilosa , Carbono , Óxido Ferrosoférrico/química , Sustancias Reductoras , Iones
15.
Foods ; 11(8)2022 Apr 09.
Artículo en Inglés | MEDLINE | ID: mdl-35454674

RESUMEN

To investigate the physicochemical, structural, and rheological characteristics of starch from wheat cultivars varying in grain hardness index employed in making jiuqu and to interrelate grain hardness index with physicochemical and structural properties of starch. Starch extracted therefrom was investigated for structural and physicochemical properties. Starch granules showed relatively wide granule size distribution; large size granules showed lenticular shapes while medium and small size granules exhibited spherical or irregular shapes. Starch from wheat with a lower grain hardness index exhibited a relatively higher degree of crystallinity. Chain-length profiles of amylopectin showed distinct differences; among the fractions of fa, fb1, fb2, and fb3 representing the weight-based chain-length proportions in amylopectin, the fa fractions ranged from 19.7% to 21.6%, the fb1 fractions ranged from 44.4% to 45.6%, the fb2 fractions ranged from 16.2% to 17.0%, and the fb3 fractions ranged from 16.1% to 18.8%, respectively. To, Tp, Tc, and ∆H of starch ranged from 57.8 to 59.7 °C, 61.9 to 64.2 °C, 67.4 to 69.8 °C, and 11.9 to 12.7 J/g, respectively. Peak viscosity, hot pasting viscosity, cool pasting viscosity, breakdown, and setback of starch ranged from 127 to 221 RVU, 77 to 106 RVU, 217 to 324 RVU, 44 to 116 RVU, and 137 to 218 RVU, respectively. Both G' and G" increased in the frequency range of 0.628 to 125.6 rad/s; the wheat starch gels were more solid-like during the whole range of frequency sweep.

16.
Food Funct ; 13(8): 4331-4343, 2022 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-35302147

RESUMEN

Depression remains one of the most prevalent psychiatric disorders, and it has been confirmed that it is related to the dysfunction of the microbiota-gut-brain axis. Manipulation of the gut microenvironment by probiotics might improve mental health and prevent stress-related psychiatric disorders. The present study aimed to determine whether Lactobacillus rhamnosus (L. rhamnosus) zz-1 could prevent the occurrence of depression and its potential mechanisms using a mouse model with chronic unpredictable mild stress (CUMS). The results indicated that L. rhamnosus zz-1 intervention ameliorated CUMS-induced depression-like behaviors of mice with reduced body growth rate, lowered sucrose preference, increased immobility time, as well as decreased curiosity and mobility. Moreover, L. rhamnosus zz-1 significantly inhibited hormones released due to hyperactivity of the hypothalamic-pituitary-adrenal (HPA) axis, alleviated CUMS-induced deficits of monoamine neurotransmitters, and increased the expression of brain-derived neurotrophic factor (BDNF) and tyrosine kinase receptor B (TrkB). These benefits were partially linked to the regulation of the intestinal microenvironment. L. rhamnosus zz-1 alleviated intestinal damage and reduced intestinal inflammation of the depressed mice. Meanwhile, L. rhamnosus zz-1 effectively adjusted the dysbiosis of mouse gut microbiota induced by CUMS, such as changes in the abundance of the Lachnospiraceae NK4A136 group, Bacteroides, and Muribaculum. Taken together, these results demonstrated that L. rhamnosus zz-1 was effective in preventing depression from chronic stress, adding new evidence to support the mental benefits of probiotics.


Asunto(s)
Lacticaseibacillus rhamnosus , Animales , Factor Neurotrófico Derivado del Encéfalo/genética , Factor Neurotrófico Derivado del Encéfalo/metabolismo , Depresión/metabolismo , Modelos Animales de Enfermedad , Humanos , Sistema Hipotálamo-Hipofisario , Lacticaseibacillus rhamnosus/metabolismo , Sistema Hipófiso-Suprarrenal/metabolismo , Estrés Psicológico/metabolismo
17.
J Colloid Interface Sci ; 608(Pt 1): 768-779, 2022 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-34689109

RESUMEN

In this work, a rapid coprecipitation reaction is developed to obtain nano-sized Zn-doped tin oxide samples (Zn-SnO-II or Zn-SnO2-IV) for the first time by simply mixing tin ion (Sn2+ or Sn4+) and zinc ion (Zn2+) containing salts in a mild aqueous condition. Characterization results illustrate the Zn-SnO-II sample is constituted by an overwhelming quantity of Zn-doped SnO nanobelts and a small quantity of Zn-doped SnO2 nanoparticles. The redox reaction between the Sn2+ ions from the Zn-SnO-II sample and the surface oxygen-containing functional groups from functionalized carbon nanotube (F-CNT) and graphene oxide (GO) leads to the formation of the final Zn-SnO2/CNT@RGO composites. As an anode active material for lithium-ion batteries, the Zn-SnO2/CNT@RGO product showed superior electrochemical performance than the controlled Zn-SnO2/CNT and Zn-SnO2/RGO samples, which had a high gravimetric capacity of 901.3 mAh·g-1 at a high charge and discharge current of 1000 mA·g-1 after 300 cycles and excellent rate capability. The reaction mechanism for the successful synthesis of the Zn-doped tin oxide samples has been proposed, and the insight into the outstanding lithium-ion storage performance for the Zn-SnO2/CNT@RGO composite has been revealed. The synthetic processes for both the Zn-doped tin oxides and derived carbon supported composites are straightforward and involve no harsh conditions nor complicated treatment, which have good potential for massive production and application in wider fields.

18.
Parasitol Res ; 121(1): 461-464, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34750654

RESUMEN

Malaria is one of the most important parasitic diseases that causes a serious public health problem. The genetic diversity of malaria parasites may affect malaria transmission and malaria control strategies. In China, imported malaria was significantly increased in recent years, among which numerous migrant workers were infected with Plasmodium falciparum from Africa. However, little was known about genetic diversity of these populations in China. In this study, we evaluated genetic polymorphism and allele frequencies of msp1, msp2, and glurp genes in P. falciparum among Chinese migrant workers returnee from Africa between 2013 and 2017. Of the 381 P. falciparum isolates, 89.0% for msp1 gene, 71.7% for msp2 gene, and 78.0% for glurp gene were successfully genotyped. In msp1, 29 different alleles were observed, among which the K1 allelic family (71.7%) was predominant. In msp2, 21 different alleles were detected, of which the 3D7 allelic family (91.2%) was more frequent than FC27 allelic family (72.5%). For glurp, 12 individual alleles were detected in the samples. Taken together, the findings showed a high genetic diversity of these isolates, which provided the baseline data for African P. falciparum population imported to China.


Asunto(s)
Malaria Falciparum , Migrantes , África , Alelos , Antígenos de Protozoos , China , Variación Genética , Genotipo , Humanos , Plasmodium falciparum/genética , Proteínas Protozoarias/genética
19.
J Colloid Interface Sci ; 608(Pt 2): 1707-1717, 2022 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-34742085

RESUMEN

Immobilizing nanosized electrochemically active materials with supportive carbonaceous framework usually brings in improved lithium-ion storage performance. In this work, magnetite nanoparticles (Fe3O4) are stabilized by both porous carbon domains (PC) and reduced graphene oxide sheets (RGO) to form a hierarchical composite (Fe3O4@PC/RGO) via a straightforward approach. The PC confined iron nanoparticle intermediate sample (Fe@PC) was first fabricated, where sodium carboxymethylcellulose (Na-CMC) was employed not only as a cross-linker to trap ferric ions for synthesizing a Fe-CMC precursor sample, but also as the carbon source for PC domains and iron source for Fe nanoparticles in a pyrolysis process. The final redox reaction between Fe@PC and few-layered graphene oxide (GO) sheets contributed to the formation of Fe3O4 nanoparticles with reduced size, avoiding any severe aggregation or excessive exposure. The Fe3O4@PC/RGO sample delivered a specific capacity of 522.2 mAh·g-1 under a current rate of 1000 mA·g-1 for 650 cycles. The engineered Fe@PC and Fe3O4@PC/RGO samples have good prospects for application in wider fields.

20.
Materials (Basel) ; 16(1)2022 Dec 29.
Artículo en Inglés | MEDLINE | ID: mdl-36614658

RESUMEN

In this work, magnetite nanoparticles (Fe3O4) that are well dispersed by a submicron sized carbon framework in a pomegranate shape are engineered using a flexible one-step spray pyrolysis strategy. Under inert gas atmosphere, the homogeneously mixed Fe3+ ions and chitosan (CS) molecules are in situ transformed to Fe3O4 nanoparticles and spherical nitrogen-doped carbon coating domains, respectively. Moreover, the obtained Fe3O4@C composite exhibits a unique submicron sized pomegranate configuration, in which favorable electric/ionic pathways have been constructed and the Fe3O4 nanoparticles have been effectively dispersed. When used as an anode electrochemical active material, the Fe3O4@C composite exhibits impressive lithium-ion storage capabilities, and maintains a reversible capacity of 500.2 mAh·g-1 after 500 cycles at a high current density of 1000 mA·g-1 as well as good rate capability. The strategy in this work is straightforward and effective, and the synthesized Fe3O4@C material has good potential in wider applications.

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