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1.
Inorg Chem ; 61(47): 18899-18906, 2022 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-36367771

RESUMO

The extreme magnetoresistance (XMR) of some compounds, challenging our understanding of magnetoresistance, is an interesting topic in condensed-matter and materials physics and future device applications. Here, we reported magnetotransport and magnetic properties of the as-grown and post-annealed TaCo2Te2 single crystals. The resistivity evolution with temperature in the two TaCo2Te2 single crystals shows a metallic behavior. Below 50 K, the XMR effect for the two crystals is found, and MR values at 3 K under 9 T are about 3.72 × 103% for the as-grown TaCo2Te2 and 5.71 × 102% for the annealed samples, larger than that of the previous report. The studies on the Hall effect of the two TaCo2Te2 single crystals indicate the multiband feature with high carrier mobilities from a two-band model. Electron and hole concentrations and mobilities of as-grown samples are comparable, while for the annealed sample, the hole concentration and mobility are larger than the electron concentration and mobility. The carrier mobilities for the two TaCo2Te2 single crystals have the same order of magnitude, ∼103 cm2 V-1 s-1. The XMR effect may be from high carrier mobilities. Magnetization of the as-grown TaCo2Te2 decreases with increasing temperature, and a weaker magnetic transition at ∼150 K is observed. The annealed TaCo2Te2 shows no magnetic transition and just a paramagnetic behavior with rising temperature. These results indicate that defects/deficiencies may play an important role in magnetotransport and magnetic properties of the two TaCo2Te2 single crystals. These results are helpful in deeply understanding the XMR mechanism and magnetic properties in TaCo2Te2 and offer a way to study the magnetic properties of the XMR Co-Te system.

2.
Sensors (Basel) ; 23(1)2022 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-36616881

RESUMO

The precise separation of rice particles is an important step in rice processing. In this paper, discrete element simulations of the motion of rice particles of different integrity in an indented cylinder separator were carried out using numerical simulation methods. The effects of single factors (cylinder rotation rate, cylinder axial inclination angle, and collection trough inclination angle) on the motion trajectories of particles are investigated and the probability distribution functions of particles are obtained. The statistical method of Kullback-Leibler divergence is used to quantitatively evaluate the differences in the probability distribution functions of the escape angles of particles of different degrees of integrity. The purpose of this paper is to determine the optimum parameters for an indent cylinder separator by understanding the material cylinder separating process from particle scale and to provide a basis for the numerical design of a grain particle cylinder separators.


Assuntos
Oryza , Movimento (Física)
3.
J Fluoresc ; 30(3): 687-694, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32378115

RESUMO

The influences of metal atoms on optimized geometry structures, relative energies, frontline molecular orbitals, and binding energies of metalloporphyrin-based fluorescent array sensor were systematically investigated by density functional theory (DFT) at B3LYP/LAN2DZ level. DFT calculated results reveal that the selected metal atoms in the center of the metalloporphyrin plane provide difference performances of metalloporphyrin-based fluorescent array sensor for the rapid determination of trimethylamine. The calculated binding energies have displayed in the following order at the most stable states: zinc porphyrin (ZnP) < copper porphyrin (CuP) < silver porphyrin (AgP) < iron porphyrin (FeP) < tin porphyrin (SnP) < cobalt porphyrin (CoP) < ruthenium porphyrin (RuP) < manganese porphyrin (MnP). Therefore, this theoretical study provides a design mechanism for how to choose a proper metal atom for low or high concentration trimethylamine. This research also suggests that theoretical results may be useful for the rapid detection of food containing trimethylamine.

4.
Spectrochim Acta A Mol Biomol Spectrosc ; 265: 120337, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34530201

RESUMO

A rapid method based on three-dimensional synchronous fluorescence spectroscopy was developed for emulsion oxidation evaluation. This method was selected because of its high sensitivity to dissolved organic matter typically occurring in the lipid oxidation. Spectral signal and chemical reference measurements were recorded for each emulsion sample as input and output data for the model construction. Characteristic values were extracted from the spectral data by the application of parallel factor (PARAFAC) analysis. Partial least squares regression (PLSR) was then used to construct a regression model for the rapid determination of emulsion oxidation. The correlation coefficient of the calibration and prediction sets were used as the performance parameters for the PLSR models as follows: R = 0.929, 0.973 for emulsion samples stored at 25℃; R = 0.897, 0.903 for emulsion samples stored at 70℃. The overall results demonstrated that the fluorescence spectroscopy, coupled with PARAFAC and PLSR algorithms, could be successfully used as a rapid method for the emulsion oxidation evaluation.


Assuntos
Espectroscopia de Luz Próxima ao Infravermelho , Calibragem , Emulsões , Estudos de Viabilidade , Análise dos Mínimos Quadrados , Espectrometria de Fluorescência
5.
Artigo em Inglês | MEDLINE | ID: mdl-21584197

RESUMO

We present a case of a 24-year-old man who presented hematuria after the orthopedic tuina, which has not been recorded previously in the literature. We review complications of tuina in the literature too.

6.
Food Chem ; 342: 128242, 2021 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-33069532

RESUMO

The purpose of this study was to construct a fusion model using probe-based and non-probe-based fluorescence spectroscopy and low-field nuclear magnetic resonance spectroscopy (Low-field NMR) for rapid quality evaluation of frying oil. Iron tetraphenylporphyrin (FeTPP) was selected as the probe to detect polar compounds in frying oil samples. Non-probe-based fluorescence spectroscopy and low-field NMR were employed to determine the fluorescence changes of antioxidants, triglycerides and fatty acids in frying oil samples. Compared to the models constructed using non-fusion data, the fusion-data models achieved a better regression prediction performance and correlation coefficients with values of 0.9837 and 0.9823 for the training and test sets, respectively. This study suggested that the multiple data fusion method was capable to construct better regression models to rapidly evaluate the quality of frying oil and other food with high oil contents.


Assuntos
Culinária , Espectroscopia de Ressonância Magnética , Óleos de Plantas/química , Espectrometria de Fluorescência , Ácidos Graxos/análise , Temperatura Alta , Triglicerídeos/análise
7.
Artigo em Inglês | MEDLINE | ID: mdl-30954795

RESUMO

This study attempted to develop a probe-based fluorescence technology as a rapid method to discriminate the oxidation degree of oil. The fluorescence probe was made by dissolving the selected probe in a chloroform solvent. A fluorescence landscape profile for each oil sample was obtained to discriminate fluorescence changes during the oxidation process. Parallel factor analysis (PARAFAC) was performed to extract characteristic fluorescence peaks. Then, these characteristic fluorescence peaks and chemical indicators were used to build regression models based on support vector regression (SVR). The correlation coefficients (R) and mean squared error (MSE) in the prediction sets were applied as the assessment parameters for the SVR models as follows: R = 0.9724, MSE = 0.0088 for an acid value. This research suggests that probe-based fluorescence spectroscopy is useful for oxidation evaluation of oil and perhaps other food containing high amounts of oil.


Assuntos
Corantes Fluorescentes/química , Análise de Alimentos/métodos , Contaminação de Alimentos/análise , Óleo de Palmeira/química , Clorofórmio , Análise Fatorial , Fluorescência , Qualidade dos Alimentos , Oxirredução , Solventes , Espectrometria de Fluorescência/métodos , Máquina de Vetores de Suporte
8.
Zhongguo Gu Shang ; 25(8): 674-7, 2012 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-25058962

RESUMO

OBJECTIVE: To compare therapeutic effects between suspine rotation and flexion manipulation for treating lumbar disc herniation. METHODS: From December 2008 to January 2011, 134 patients with lumbar disc herniation were treated, including 74 males and 60 females,ranging in age from 17 to 67 years,33 patients with age over 50 years old. According to diagnosis the ladder of the 9 cases bulging type, 74 hernia type, 51 cases free type. The patients were randomly divided into treatment group ( 69 cases) and control group (65 cases). All the patients were treated with the three-dimensional computer-controlled traction therapeutic apparatus,with continued traction for 20 minutes. After traction, flexion manipulation and rotat-ing manipulation were respectively adopted in treatment group and control group (on alternate days one time, 3 times as a course of treatment). The symptoms and signs (including back pain and discomfort, lower limb pain and numbness, powerless urination and defecation,numbness in perineum, straight-leg raising degree,ability of lower extremity walking,work and live) of patients were observed after treatment. RESULTS: All patients were followed up for 0.5 to 6 months with an average of 1.1 months. After treatment, the symptoms and signs of patients have significantly improved (P < 0.01), but the symptomes of powerless urination and defecation,numbness in perineum was not improved obviously (P>0.05). Forty-two of 69 patients in treatment group got excellent result, moderate in 20, poor in 7; Twenty of 65 patients in control group got excellent result, moderate in 25,poor in 20. CONCLUSION: The whole effect of lumbar backwards rotation manipulation is more satisfactory than flexsion manipulation for treating lumbar intervertebral disc herniation. But spinning force and times should be noticed.


Assuntos
Deslocamento do Disco Intervertebral/terapia , Vértebras Lombares , Manipulação Ortopédica/métodos , Rotação , Adolescente , Adulto , Idoso , Estudos de Casos e Controles , Feminino , Humanos , Deslocamento do Disco Intervertebral/fisiopatologia , Vértebras Lombares/fisiopatologia , Masculino , Pessoa de Meia-Idade , Recuperação de Função Fisiológica , Adulto Jovem
9.
Zhongguo Gu Shang ; 23(8): 626-8, 2010 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-20860145

RESUMO

OBJECTIVE: To study the clinical efficacy of the frog shape four-step pulling method for the treatment of sacroiliac joint subluxation, and to explore the rationality of the method. METHODS: Among 92 patients diagnosed as sacroiliac joint subluxation, 19 patients were male and 73 patients were female,ranging in age from 14 to 61 years, with an average of 38.7 years. The course of disease ranged from 1 month to 96 months,with an average of 18.4 months. All the patients were treated with the frog shape four-step pulling method. The therapeutic effects were observed. RESULTS: The treatment times ranged from 1 to 10 (averaged 4.3 times). According to evaluation standard of sacroiliac joint subluxation, 71 patients got an excellent result, 19 good, 1 fair and 1 bad. CONCLUSION: The frog shape four-step pulling method had many advantages such as simplicity of operation, targeted, high rate of success, not easy rebound and less pain for patients and so on.


Assuntos
Luxações Articulares/terapia , Manipulação Ortopédica/métodos , Articulação Sacroilíaca/lesões , Adolescente , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
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