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1.
ChemSusChem ; 12(10): 2286-2293, 2019 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-30802352

RESUMO

Recently, the ternary spinel selenide MgSc2 Se4 was proposed to have high magnesium ion mobility and is therefore an interesting potential candidate as a solid electrolyte in magnesium secondary batteries. To test the properties of the material, a modified solid-state reaction was used to synthesize pure MgSc2 Se4 . Electrochemical characterizations identified detrimental high electronic conductivities, which limit its application as a Mg-conducting solid electrolyte. Two methods were attempted to lower electronic conductivities, including the implementation of Se-rich phases and aliovalent doping, however, with no sufficient improvement. Based on the mixed conducting properties of MgSc2 Se4 , a reversible insertion/extraction of Mg2+ into the spinel structure could be demonstrated.

2.
Chem Sci ; 9(2): 457-462, 2018 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-30310560

RESUMO

The core-shell structure of endohedral fullerenes results in good protection of the encapsulated spin carriers from the environment. In this research, the quantum coherence behavior of the endohedral fullerene Sc3C2@C80 in CS2 solution is characterized from 5 K to room temperature. Below the critical temperature of around 140 K, the inner group is hindered, and the EPR spectrum consists of a single broad line. The spin carriers display a maximum phase memory time of 17.2(7) µs at 10 K. In the high temperature region, the inner group is mobile, and the EPR spectrum consists of 22 homogeneously broadened lines due to isotropic hyperfine coupling. The maximum phase memory time for each transition is around 139(1) ns at 200 K which allows arbitrary superposition state manipulations to be performed. This research demonstrates that Sc3C2@C80 displays temperature-crossover behaviour due to weak interaction between the Sc3C2 core and the C80 shell.

3.
ACS Appl Mater Interfaces ; 10(21): 18005-18011, 2018 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-29717868

RESUMO

The poor contact between the solid-state electrolyte and cathode materials leads to a high interfacial resistance, severely limiting the rate capability of solid Li metal batteries. Herein, an integrative battery design is introduced with a gradiently polymerized solid electrolyte (GPSE), a microchannel current collector array, and nanosized cathode particles. An in situ formed GPSE encapsulates cathode nanoparticles in the microchannel with ductile inclusions to lower the interfacial impedance, and the stiff surface layer of GPSE toward anode suppresses the Li dendrite growth. The Li metal batteries based on GPSE and the Li-free hydrogenated V2O5 (V2O5-H) cathode exhibit an outstanding high rate response of up to 5 C (the capacity ratio of 5 C/1 C is 90.3%) and an ultralow capacity fade rate of 0.07% per cycle over 300 cycles. The other Li-containing cathodes such as LiFePO4 and LiNi0.5Mn0.3Co0.2O2 can also operate effectively at the rates of 5 and 2 C, respectively. Such an ingenious design may provide new insights into other solid metal batteries through an interfacial engineering manipulation at the micro- and nanolevel.

4.
Chin J Nat Med ; 15(1): 62-70, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28259254

RESUMO

Boiling processing is commonly used in post-harvest handling of White Paeony Root (WPR), in order to whiten the herbal materials and preserve the bright color, since such WPR is empirically considered to possess a higher quality. The present study was designed to investigate whether and how the boiling processing affects overall quality of WPR. First, an ultra-high performance liquid chromatography quadrupole/time-of-flight mass spectrometry-based metabolomics approach coupled with multivariate statistical analysis was developed to compare the holistic quality of boiled and un-boiled WPR samples. Second, ten major components in WPR samples boiled for different durations were quantitatively determined using high performance liquid chromatography to further explore the effects of boiling time on the holistic quality of WPR, meanwhile the appearance of the processed herbal materials was observed. The results suggested that the boiling processing conspicuously affected the holistic quality of WPR by simultaneously and inconsistently altering the chemical compositions and that short-time boiling processing between 2 and 10 min could both make the WPR bright-colored and improve the contents of major bioactive components, which were not achieved either without boiling or with prolonged boiling. In conclusion, short-term boiling (2-10 min) is recommended for post-harvest handling of WPR.


Assuntos
Medicamentos de Ervas Chinesas/normas , Temperatura Alta , Paeonia/química , Cromatografia Líquida de Alta Pressão/métodos , Medicamentos de Ervas Chinesas/química , Espectrometria de Massas/métodos , Raízes de Plantas/química , Tecnologia Farmacêutica , Água
5.
J Pharm Biomed Anal ; 98: 424-33, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25011060

RESUMO

In this study, a improved high performance liquid chromatography-diode array detector (HPLC-DAD) method for simultaneous quantification of twelve major components belonging to three chemical types was developed and validated, and was applied to quantitatively compare the quality of Radix Paeoniae Alba (RPA) sulfur-fumigated with different durations and purchased from commercial herbal markets. The contents of paeoniflorin, benzoylpaeoniflorin, oxypaeoniflorin, benzoic acid and paeonol decreased whereas that of paeoniflorin sulfonate increased in RPA with the extending of sulfur-fumigation duration. Different levels of paeoniflorin sulfonate were determined in ten of seventeen commercial RPA samples, indicating that these ten samples may be sulfur-fumigated with different durations. Moreover, the relative standard deviation of the contents of each component was higher in the commercial sulfur-fumigated RPA samples than that in commercial non-fumigated RPA samples, and the percentage of the total average content of monoterpene glycosides in the determined analytes was higher in the decoctions of commercial sulfur-fumigated RPA than that in commercial non-fumigated RPA samples. All these results suggested that the established method was precise, accurate and sensitive enough for the global quality evaluation of sulfur-fumigated RPA, and sulfur-fumigation can not only change the proportions of bioactive components, but also cause the reduction of the quality consistency of both raw materials and aqueous decoctions of RPA.


Assuntos
Paeonia/química , Enxofre/química , Acetofenonas/química , Ácido Benzoico/química , Cromatografia Líquida de Alta Pressão/métodos , Medicamentos de Ervas Chinesas/química , Fumigação/métodos , Glucosídeos/química , Glicosídeos/química , Medicina Herbária/métodos , Monoterpenos/química , Raízes de Plantas/química
6.
Chemphyschem ; 15(13): 2780-4, 2014 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-25045089

RESUMO

Sc(2)S@C(84) has recently been detected but not structurally characterized.1 Density functional theory calculations on C(84) and Sc(2)S@C(84) show that the favored isomer of Sc(2)S@C84 shares the same parent cage as Sc(2)C2@C(84), whereas Sc(2)S@C(84):51383, which violates the isolated-pentagon rule, is the second lowest energy isomer with the widest HOMO-LUMO gap and shows high kinetic stability. The analysis shows that Sc(2)S@C(84):51575 is favored when the temperature exceeds 2,800 K and it can transform into the most favorable isomer Sc(2)S@C(84):51591. Molecular orbital analysis indicates that both Sc(2)S and Sc(2)C(2) formally transfer four electrons to the cage, and quantum theory of atoms in molecules analysis demonstrates that there is a covalent interaction between Sc(2)S and C(84):51591. The IR spectra of Sc(2)S@C(84) are provided to aid future structural identification.

7.
Chem Commun (Camb) ; 50(71): 10307-10, 2014 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-25058657

RESUMO

C60 fullerenol was found to be a highly active, selective and stable catalyst for cycloaddition between CO2 and epoxides to produce various cyclic carbonates with excellent yields (89-99%). A solid/liquid interfacial hydrogen-bond assisted mechanism was proposed to account for its high efficiency.

8.
Chem Asian J ; 9(5): 1265-9, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24596336

RESUMO

Nanometer-sized flakes of MnV2O6 were synthesized by a hydrothermal method. No surfactant, expensive metal salt, or alkali reagent was used. These MnV2O6 nanoflakes present a high discharge capacity of 768 mA h g(-1) at 200 mA g(-1), good rate capacity, and excellent cycling stability. Further investigation demonstrates that the nanoflake structure and the specific crystal structure make the prepared MnV2O6 a suitable material for lithium-ion batteries.

9.
Bioprocess Biosyst Eng ; 37(9): 1789-97, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24577738

RESUMO

Polysaccharides and ganoderic acids (GAs) are the major bioactive constituents of Ganoderma species. However, the commercialization of their production was limited by low yield in the submerged culture of Ganoderma despite improvement made in recent years. In this work, twelve Ganoderma strains were screened to efficiently produce polysaccharides and GAs, and Ganoderma lucidum 5.26 (GL 5.26) that had been never reported in fermentation process was found to be most efficient among the tested stains. Then, the fermentation medium was optimized for GL 5.26 by statistical method. Firstly, glucose and yeast extract were found to be the optimum carbon source and nitrogen source according to the single-factor tests. Ferric sulfate was found to have significant effect on GL 5.26 biomass production according to the results of Plackett-Burman design. The concentrations of glucose, yeast extract and ferric sulfate were further optimized by response surface methodology. The optimum medium composition was 55 g/L of glucose, 14 g/L of yeast extract, 0.3 g/L of ferric acid, with other medium components unchanged. The optimized medium was testified in the 10-L bioreactor, and the production of biomass, IPS, total GAs and GA-T enhanced by 85, 27, 49 and 93 %, respectively, compared to the initial medium. The fermentation process was scaled up to 300-L bioreactor; it showed good IPS (3.6 g/L) and GAs (670 mg/L) production. The biomass was 23.9 g/L in 300-L bioreactor, which was the highest biomass production in pilot scale. According to this study, the strain GL 5.26 showed good fermentation property by optimizing the medium. It might be a candidate industrial strain by further process optimization and scale-up study.


Assuntos
Fermentação , Ganoderma/metabolismo , Polissacarídeos/metabolismo , Triterpenos/metabolismo , Reatores Biológicos , Meios de Cultura , Modelos Teóricos
10.
J Nanosci Nanotechnol ; 12(3): 2254-60, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22755045

RESUMO

By means of the density functional theory calculations, two C88(D2:35)-based endohedral fullerenes, Lu3C2@C88(D2:35) and Lu3N@C88(D2:35) which encapsulate tri-lutetium carbide and tri-lutetium nitride cluster were investigated. For the cores in Lu3C2@C88 and Lu3N@C88, the trivalent C2 and N respectively template a butterfly-shaped endohedral moiety and a planar tri-lutetium cluster within the same D2-symmetric C88 cage. Moreover, Lu3N@C88 - D2 has a closed-shell electronic structure but for LuC3C2@C88 - D2, it owns an unpaired electron mainly localized on the internal Lu3C2 cluster. These results clearly showed that the core unit C2(3) as well as N3- play an important role in constructing molecular structures and electronic features of metallofullerenes. Furthermore, the electrochemical redox potentials, and vibrational frequencies of the two endofullerenes agree well with our experimental results. The electronic structures, ionization energies, electron affinities, inner clusters' dynamic motions of them have been predicted to further disclose the characters of these two metallofullerenes.

11.
Nanoscale ; 4(12): 3669-72, 2012 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-22617872

RESUMO

A FAR over-expressed tumor targeting multifunctional imaging probe has been fabricated based on gadofulleride nanoplatform. The combination of highly efficient MRI contrast enhancement and sensitive fluorescence imaging along with the preferential uptake toward FAR tumor cells suggest that the obtained multifunctional imaging probe possesses complementary capabilities for anatomical resolution and detection sensitivity.

12.
J Am Chem Soc ; 132(46): 16362-4, 2010 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-21047077

RESUMO

The endohedral fullerene Sc(3)NC@C(80)-I(h) has been synthesized and characterized; it has an unprecedented planar quinary cluster in a fullerene cage. It is also the first chemical compound in which the presence of an unprecedented (NC)(3-) trianion has been disclosed. The fascinating intramolecular dynamics in Sc(3)NC@C(80)-I(h) enables the whole molecule to display high polarity and promising ferroelectricity. This finding inspires the possibility that such a planar quinary cluster may be useful in constructing many other endohedral fullerenes.

13.
J Am Chem Soc ; 131(46): 16646-7, 2009 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-19877678

RESUMO

For the first time, we have produced the stable compound Sc(4)C(2)@C(80)-I(h) and characterized it as a metal carbide endofullerene by FTIR and Raman spectroscopies in combination with DFT calculations. Furthermore, DFT calculations have demonstrated that this molecule has a Russian-doll-type structure, C(2)@Sc(4)@C(80).

15.
Zhongguo Zhong Yao Za Zhi ; 33(5): 553-6, 2008 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-18536382

RESUMO

OBJECTIVE: Observe the effects of Goutengsan on SOD, MAO-B, GSH-PX, NO, LDH, index of brain, rate of death and so on in rats to study therapeutic effects and mechanism of Goutengsan on Alzheimer dementia (AD) model. METHOD: One hundred and twenty rats were randomly divided into 6 groups, 3 experimental groups of which were daily administrated with Goutengsan extract whereas the model and control groups were given NS (0.01 mL x g(-1)). Aniracetam at 0.1 g x kg(-1) served as a positive control. At the 5th day after administration, all groups except the control were administrated (ip) with AlCl3 (100 mg x kg(-1) ) for successive 50 days at 1 day interval. After administration, the death rate, body weight, training scores, brain index, MAO-B, SOD, GSH-Px in brain and NO, LDH in serum were determined. RESULT: The brain index, SOD, GSH-Px activities as well as NO content of drug-treated groups were strikingly higher that of model group, and had not obvious difference from that of normal group except content of LDH was higher. CONCLUSION: Goutengsan could increase the brain index, cut down the rate of death, stable increase of body weight, promote the endogenous antioxidant activity, enhance the clearance of lipid peroxide and other metabolic waste, inhibit the MAO-B activity, reduced the leakage of LDH and maintain the content of NO at a normal level. Therefore Goutengsan could protect cells, delay senile, improve symptoms of AD.


Assuntos
Compostos de Alumínio/farmacologia , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/metabolismo , Cloretos/farmacologia , Medicamentos de Ervas Chinesas/farmacologia , Cloreto de Alumínio , Doença de Alzheimer/induzido quimicamente , Animais , Peso Corporal/efeitos dos fármacos , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Modelos Animais de Doenças , Feminino , Glutationa Peroxidase/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Masculino , Malondialdeído/metabolismo , Memória/efeitos dos fármacos , Óxido Nítrico/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Pirrolidinonas/farmacologia , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Superóxido Dismutase/metabolismo
16.
Bioconjug Chem ; 19(3): 651-5, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18254583

RESUMO

Water-soluble gadofullerides exhibited high efficiency as magnetic resonance imaging (MRI) contrast agents. In this paper, we report the conjugation of the newly synthesized gadofulleride, Gd@C82O6(OH) 16(-)(NHCH2CH2COOH)8, with the antibody of green fluorescence protein (anti-GFP), as a model for "tumor targeted" imaging agents based on endohedral metallofullerenes. In this model system, the activity of the anti-GFP conjugate can be conveniently detected by green fluorescence protein (GFP), leading to in vitro experiments more direct and facile than those of tumor antibodies. Objective-type total internal reflection fluorescence microscopy revealed that each gadofulleride aggregate conjugated on average five anti-GFPs, and the activity of anti-GFPs was preserved after conjugation. In addition, the gadofulleride/antibody conjugate exhibited higher water proton relaxivity (12.0 mM (-1) s (-1)) than the parent gadofulleride aggregate (8.1 mM (-1) s (-1)) in phosphate buffered saline at 0.35 T, as also confirmed by T1-weighted images of phantoms. These observations clearly indicate that the synthesized gadofulleride/antibody conjugate not only has targeting potential, but also exhibits higher efficiency as an MRI contrast agent.


Assuntos
Anticorpos/química , Meios de Contraste/síntese química , Gadolínio/química , Imagem por Ressonância Magnética/métodos , Biotina/química , Fenômenos Químicos , Físico-Química , Proteínas de Fluorescência Verde/imunologia , Indicadores e Reagentes , Conformação Molecular , Peso Molecular , Soroalbumina Bovina/química , Solubilidade , Espectrometria de Fluorescência , Estreptavidina/química , Água
17.
J Phys Chem B ; 111(51): 14223-6, 2007 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-18047312

RESUMO

Two new water-soluble Gd-containing endohedral metallofullerenes [ScxGd3-xN@C80OmOHn (x = 1, 2; m approximately 12; n approximately 26)] were synthesized in a simple one-step reaction and characterized by Fourier transform (FT)-IR as well as X-ray photoelectron spectroscopy (XPS). Their observed longitudinal relaxivities (R1) for water protons are 20.7 and 17.6 mM(-1) s(-1), respectively, which are significantly higher than that of the commercial magnetic resonance imaging (MRI) contrast agent (Gd-DTPA, 3.2 mM(-1) s(-1)). These results indicate these trimetallic nitride endohedral fullerenols are potential next-generation high-efficiency MRI contrast agents.

19.
J Nanosci Nanotechnol ; 7(7): 2487-93, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17663269

RESUMO

We report a facile hydrothermal synthetic approach to selectively produce 1-dimensional, 2-dimensional, or 3-dimensional MnO2 nanomaterials reliably and conveniently. The influences of reaction conditions on the morphology and crystallographic forms and the formation mechanism of the as-obtained MnO2 nanostructures have been studied in this work. And the materials produced by this method have excellent crystalline nature. Preliminary electrochemical study indicates that the as-prepared 2-dimensional MnO2 nanomaterials are excellent cathode materials using in lithium batteries.


Assuntos
Cristalização/métodos , Eletroquímica/métodos , Compostos de Manganês/química , Nanoestruturas/química , Nanoestruturas/ultraestrutura , Nanotecnologia/métodos , Óxidos/química , Condutividade Elétrica , Instalação Elétrica/instrumentação , Instalação Elétrica/métodos , Substâncias Macromoleculares/química , Teste de Materiais , Conformação Molecular , Tamanho da Partícula , Propriedades de Superfície
20.
Org Lett ; 9(10): 2011-3, 2007 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-17447779

RESUMO

We report a combined experimental and theoretical investigation on the regiochemistry of a series of TNT endohedral fullerenes ScxGd3-xN@C80 (x = 0-3) in 1,3-dipolar cycloadditions, which demonstrates that the regioselectivity of the TNT-based endohedral fullerenes ScxGd3-xN@C80 (x = 0-3) in the exohedral cycloadditions depends remarkably on the size of the encaged cluster.

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