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1.
Nano Lett ; 24(19): 5714-5721, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38695488

RESUMO

The structure of solvated Li+ has a significant influence on the electrolyte/electrode interphase (EEI) components and desolvation energy barrier, which are two key factors in determining the Li+ diffusion kinetics in lithium metal batteries. Herein, the "solvent activity" concept is proposed to quantitatively describe the correlation between the electrolyte elements and the structure of solvated Li+. Through fitting the correlation of the electrode potential and solvent concentration, we suggest a "low-activity-solvent" electrolyte (LASE) system for deriving a stable inorganic-rich EEI. Nano LiF particles, as a model, were used to capture free solvent molecules for the formation of a LASE system. This advanced LASE not only exhibits outstanding antidendrite growth behavior but also delivers an impressive performance in Li/LiNi0.8Co0.1Mn0.1O2 cells (a capacity of 169 mAh g-1 after 250 cycles at 0.5 C).

2.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 41(7): 776-782, 2024 Jul 10.
Artigo em Zh | MEDLINE | ID: mdl-38946357

RESUMO

OBJECTIVE: To retrospectively analyze the clinical characteristics of 193 Chinese patients with McCune-Albright syndrome (MAS). METHODS: By using keywords "McCune-Albright syndrome", "Albright syndrome", or " fibrous dysplasia " as the search terms, 193 cases of MAS reported in China from January 1990 to November 2022 from the Wanfang data, CNKI, VIP, PubMed, and Embase databases were obtained, and their clinical data was retrospectively analyzed. Intergroup comparisons were carried out by using t test, Mann-Whitney U test, and X2 test. RESULTS: The 193 MAS patients had included 42 males and 151 females, with the median first-visit age of females being younger than males. The typical triad group had accounted for 46.1% of patients, and the middle first-visit and diagnosis age was younger than the atypical group. The primary reason for first-visit in males of MAS was fibrous dysplasia (FD), whilst that in females of MAS was peripheral precocious puberty (PPP). FD has occurred in 84.5% of the patients, with an average age of onset age being 6.1 years old, and 90% was ≤ 16 years of age. Endocrine hyperfunction was found in 79.3% of the patients, with a higher proportion in females compared with males (P < 0.05). Pituitary involvement was seen in 21.8% of the patients, and the incidence of craniofacial FD and cranial nerve compression was significantly higher in those with elevated growth hormone (GH) than without (P < 0.05). Café-au-Lait Spots were noted in 86.5% of the patients, and 28.3% (28/99) had located on the different side of FD. CONCLUSION: Most MAS patients had atypical manifestations and multi-systemic involvement. It is more common and occurs earlier in females. The most common reasons for initial diagnosis in male and female patients were FD and PPP, respectively. Patients with elevated GH should be examined for cranial nerve compression.


Assuntos
Displasia Fibrosa Poliostótica , Humanos , Displasia Fibrosa Poliostótica/genética , Masculino , Feminino , Criança , Adolescente , China , Pré-Escolar , Adulto , Estudos Retrospectivos , Adulto Jovem , Lactente , Povo Asiático/genética , Pessoa de Meia-Idade , População do Leste Asiático
3.
Waste Manag ; 183: 174-183, 2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-38759275

RESUMO

Solid-phase residues from pyrolysis of oily wastes (OS) are widely used due to their rich pore structure and strong adsorption capacity. In this study, pyrolysis residues (OS-P) were obtained from the pyrolysis treatment of four typical OS in Karamay, Xinjiang. The results indicate that the crystalline substances in OS-P mainly were SiO2, BaSO4, and graphite. The heavy metals of OS-P were higher than that of OS in the following order: Zn > Cu > Ni > Cr > Pb > Cd. The results of the improvement of Community Bureau of Reference (BCR) sequential extraction showed that the proportion of Cu, Ni and Cr in OS1-P in the residual fraction was higher than that of the other three OS. The residual fraction of Cu, Ni, and Cr in OS1-P increased from 16.0 %, 30.0 %, and 11.0 % to 66.1 %, 81.9 %, and 89.2 %, respectively. After pyrolysis treatment, the leaching concentration of heavy metals in the residue was reduced. Referring to the requirements for heavy metal control limits (GB 4284-2018), all heavy metals in OS-P showed low risk. Their potential ecological risk indices were 4.11, 3.13, 4.87 and 5.35, respectively, indicating that the potential ecological hazards of heavy metals from OS-P were slight. There was no significant effect on the histopathological changes of kidney, lung, liver, ovary and testis of mice, showing that the rational use of OS-P in production will not produce toxic effects on target animals. Based on risk assessment and safety evaluation, the application of OS-P is controllable, safe and reliable for resource utilization.


Assuntos
Metais Pesados , Pirólise , Metais Pesados/análise , Medição de Risco/métodos , Animais , Camundongos , China , Eliminação de Resíduos/métodos
4.
ACS Nano ; 16(10): 16898-16908, 2022 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-36169299

RESUMO

A solid electrolyte interphase (SEI) with robust mechanical property and high ionic conductivity is imperative for high-performance lithium metal batteries since it can efficiently impede the growth of notorious lithium dendrites. However, it is difficult to form such a SEI directly from an electrolyte. In this work, a crowding dilutant modified ionic liquid electrolyte (M-ILE) has been developed for this purpose. Simulations and experiments indicate that the 1,2-difluorobenzene (1,2-dfBen) dilutant not only creates a crowded electrolyte environment to promote the interaction of Li+-FSI-, leading to abundant aggregate ion pairs (AGGs), but also participates in the reduction to construct a robust and high ionic-conductive SEI. With this M-ILE, Li/LiFePO4 cells achieve a capacity retention of 96% over 250 cycles with 9.5 mg cm-2 mass loading, and Li/LiNi0.5Co0.2Mn0.3O2 cells also deliver a discharge capacity of 132 mAh g-1 with a high retention of 88% after 100 cycles. Therefore, the use of a crowding diluent is considered to be an efficient way to construct an advanced SEI for a Li anode.

5.
Mar Pollut Bull ; 131(Pt A): 515-524, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29886977

RESUMO

Effect of digestion methods on fluorescence intensity of fluorescent polystyrene (PS) beads was poorly understood, which may affect the accuracy of toxicity test of the fluorescent PS beads exposed to marine organisms. Therefore, six digestion approaches were compared on fluorescence intensities and properties of three commercial fluorescent PS beads. Among all the protocols, the digestion using KOH (10% w/v, 60 °C) (KOH-digestion) had no effect on the fluorescence intensity, morphology and composition of the three fluorescent PS beads. Moreover, the extraction efficiency ≥ 95.3 ±â€¯0.2% of fluorescent PS beads in Daphnia magna and zebrafish, confirming its feasibility in fluorescent PS beads quantitative analysis. However, the fluorescence intensities of fluorescent PS beads digested by other five protocols were significantly decreased, as well as the change of morphology and composition on fluorescent PS beads. Overall, the KOH-digestion is an optimal protocol for extracting fluorescent PS beads in biological samples.


Assuntos
Corantes/química , Poliestirenos/química , Poluentes Químicos da Água/química , Animais , Organismos Aquáticos , Fracionamento Químico/métodos , Corantes/análise , Daphnia/efeitos dos fármacos , Digestão , Fluorescência , Conteúdo Gastrointestinal/química , Hidróxidos/química , Poliestirenos/análise , Compostos de Potássio/química , Espectrometria de Fluorescência/métodos , Poluentes Químicos da Água/análise , Peixe-Zebra
6.
Huan Jing Ke Xue ; 39(8): 3927-3936, 2018 Aug 08.
Artigo em Zh | MEDLINE | ID: mdl-29998703

RESUMO

Marine microalgae, Platymonas helgolondica var. tsingtaoensis, were used as experimental subjects to study the acute toxic effects of graphene oxide (GO) and dibutyl phthalate (DBP), both individually and together. The growth of algae cells, production of photosynthetic pigments, cell permeability, and oxidative stress were investigated. The effects of GO on the algal toxicity of DBP were evaluated. The results showed that low concentrations of GO (0.1-10 mg·L-1) had no significant effect on algae density and chlorophyll production of Platymonas helgolondica var. tsingtaoensis (P<0.05). However, the algae cell permeability increased significantly with GO concentration (P<0.05) and reached 2.2 times that of the control group at 10 mg·L-1. The EC50, 96 h value of DBP for Platymonas helgolondica var. tsingtaoensis was (11.14±0. 80) mg·L-1, which, in terms of toxicity, was much higher than that of GO (EC50, 96 h>100 mg·L-1). At a GO concentration of 1 mg·L-1, the EC50, 96 h value of DBP decreased to (4.93±2.14) mg·L-1, showing that low concentrations of GO enhanced the algae toxicity of DBP. When 1 mg·L-1 of GO was added, low concentrations of DBP (0.1-2 mg·L-1) did not have any significant effect on algae density, chlorophyll production, cell permeability, ROS, and SOD. However, the inhibitory effects of high concentrations of DPB (4 mg·L-1) on algae density and chlorophyll production were enhanced by GO, thereby increasing the average ROS and SOD in algae cells by 21% and 7%, respectively. SEM images showed that GO was the primary factor responsible for increasing the coverage and packing of, and the aggregation effect on, algae cells, which could be the reasons for the increased toxicity of DBP. The results of our study can provide data to reveal the risk of novel carbon nanomaterial pollutants to marine organisms.


Assuntos
Clorófitas/efeitos dos fármacos , Dibutilftalato/toxicidade , Grafite/toxicidade , Nanopartículas/toxicidade , Clorofila/química , Óxidos
7.
Ultrasound Med Biol ; 32(3): 377-86, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16530096

RESUMO

Previously we described a video signal analysis (VSA) method for measuring backscatter and attenuation from B-Mode image data. VSA computes depth-dependent ratios of the mean echo intensity from a sample to the mean echo intensity from a reference phantom imaged using identical scanner settings. The slope of a line-fit of this ratio (expressed in dB) versus depth is related to the attenuation of the sample. This paper investigates conditions for which the echo intensity ratio versus depth is independent of transducer pulsing characteristics and instrument settings, and depends only on the properties of the sample and the reference. A theoretical model is described for the echo signal power versus depth from a uniform medium containing scatterers. The model incorporates bandwidth, frequency and media attenuation. Results show that the sample-to-reference echo intensity ratio versus depth is a curve, the departure of which from a straight line is a function of the relative attenuation of the two media, the imaging system bandwidth and the initial frequency. The model also leads to a depth-dependent "effective frequency" determination in the VSA method. Model predictions are verified using RF signals computed by an acoustic pulse-echo simulation program.


Assuntos
Simulação por Computador , Interpretação de Imagem Assistida por Computador , Ultrassonografia , Humanos , Modelos Estatísticos , Espalhamento de Radiação , Processamento de Sinais Assistido por Computador , Gravação em Vídeo
8.
Ultrason Imaging ; 29(1): 15-30, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17491296

RESUMO

Many studies have shown that atherosclerosis changes the ultrasonic attenuation properties of the vessel wall and plaque. Accurate estimation of the attenuation coefficient slope could therefore provide an early indication of atherosclerosis and the differentiation between low, mild and highly-attenuating plaque within the vessel. However, the traditional reference phantom method that fits the power spectrum in a region of interest fails to accurately estimate the attenuation coefficient for small irregular shaped ex-vivo plaque specimens. This discrepancy was primarily due to partial volume effects and the unknown backscatter coefficient of the plaque sample. We have developed a method based on the reference-phantom method that utilizes the difference in the acoustic power above and below the sample to accurately compute values of the attenuation coefficient ex vivo. Our results demonstrate that this approach overcomes the two drawbacks mentioned earlier and provides accurate estimates of the attenuation coefficient slope for small excised tissue samples.


Assuntos
Aterosclerose/diagnóstico por imagem , Aumento da Imagem/métodos , Ultrassonografia/métodos , Algoritmos , Humanos , Técnicas In Vitro , Modelos Estatísticos , Imagens de Fantasmas
9.
J Acoust Soc Am ; 117(5): 3307-18, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-15957797

RESUMO

Previous reports have shown that the variance in ultrasound attenuation measurements is reduced when spatial and frequency compounding were applied in data acquisition and analysis. This paper investigates factors affecting the efficiency of compound attenuation imaging methods. A theoretical expression is derived that predicts the correlation between attenuation versus frequency slope (beta) estimates as a function of the increment between measurement frequencies (deltaf ) and the angular separation between beam lines (Delta (theta)). Theoretical results are compared with those from attenuation measurements on tissue-mimicking phantoms and from simulation data. Both predictions and measurement results show that the correlation between beta estimates as a function of (Delta f ) is independent of the length of the radio frequency (rf) data segment over which beta is derived. However, it decreases with an increase in the length of the data segment used in power spectra estimates. In contrast, the correlation between beta estimates as a function of delta(theta) decreases when the rf data segment length is longer or the frequency of the signal is higher. O 2005 Acoustical Society of America.


Assuntos
Acústica , Modelos Teóricos , Ultrassom
10.
Ultrason Imaging ; 25(4): 245-61, 2003 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15074512

RESUMO

A method that combines both spatial and frequency compounding is described for measuring attenuation in tissue. The technique applies a reference phantom to account for imaging system dependencies of echo signals. Emphasis is given to local attenuation estimates, to reduce the variance of the attenuation measurements over small regions of interest (ROI) and to enable coarse attenuation imaging. Experiments using a uniform phantom show that the standard deviation of local attenuation estimates within a ROI drops when greater degrees of compounding are applied. Attenuation images of a specially designed phantom containing inclusions with attenuation contrast illustrate the accuracy and precision of the technique.


Assuntos
Ultrassonografia/métodos , Imagens de Fantasmas
11.
Zhonghua Xue Ye Xue Za Zhi ; 25(4): 202-4, 2004 Apr.
Artigo em Zh | MEDLINE | ID: mdl-15182555

RESUMO

OBJECTIVE: To observe the efficacy and side effect of DA/HA regimen chemotherapy for the treatment of refractory and relapsed paroxysmal nocturnal hemoglobinuria (PNH). METHODS: Eight patients with refractory and relapsed PNH were treated with DA/HA regimen chemotherapy. Three patients were treated with DA (DNR 40 mg/d, i.v.drip, the first and the second day; 20 mg/d, i.v.drip, the third day; Ara-C 100 mg/d, i.v.drip, for 5 days) and 5 patients with HA (HHT 2 - 3 mg/d, i.v.drip, for 5 days; Ara-C 100 mg/d, i.v.drip, for 5 days). RESULTS: All the 8 patients responded well: the PNH clone was diminished in five patients. Hemolysis was remitted in 6 cases. Five patients showed improvement in hematological parameters. The dosage of corticosteroid was decreased in all of them. No serious side effect was revealed. CONCLUSION: DA/HA regimen chemotherapy was safe and effective for refractory and relapsed PNH patients.


Assuntos
Hemoglobinúria Paroxística/tratamento farmacológico , Adolescente , Adulto , Citarabina/administração & dosagem , Daunorrubicina/administração & dosagem , Quimioterapia Combinada , Feminino , Glicosilfosfatidilinositóis/análise , Harringtoninas , Humanos , Masculino
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