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1.
Angew Chem Int Ed Engl ; 63(22): e202403695, 2024 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-38436549

RESUMEN

Aqueous zinc ion batteries (AZIBs) show a great potential for next-generation energy storage due to their high safety and high energy density. However, the severe side reactions of zinc negative electrode largely hinder the further application of AZIBs. Herein, trace tris(hydroxymethyl)aminomethane (Tris) additive with rich lone-pair-electrons and zincophilic sites is firstly introduced to achieve long-term and highly reversible Zn plating/stripping. Specifically, Tris not only regulates the solvation structure of Zn2+, but is also adsorbed vertically on the Zn anode surface with a changed coordination intensity during the plating/stripping process of Zn to generate an in situ dynamic adsorption layer for the first time. The dynamic adsorption layer could successively attract the solvated Zn2+ and then promote the de-solvation of the solvated Zn2+ owing to the orientation polarization with regularly-changed applied electric field, the volume rejection effect, and strong intermolecular force towards H2O of the vertically-adsorbed Tris. Therefore, an improved Zn2+-transport kinetics as well as the inhibition of side reactions of Zn anode are successfully realized. Accordingly, the Zn||Zn symmetric cell provides an ultra-long cycle life of 2600 h. Furthermore, the Zn||MnO2 full cell with Tris could demonstrate a high capacity and structural stability for practical applications.

3.
Angew Chem Int Ed Engl ; 62(11): e202217458, 2023 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-36640120

RESUMEN

Constructing efficient artificial solid electrolyte interface (SEI) film is extremely vital for the practical application of lithium metal batteries. Herein, a dense artificial SEI film, in which lithiophilic Zn/Lix Zny are uniformly but nonconsecutively dispersed in the consecutive Li+ -conductors of Lix SiOy , Li2 O and LiOH, is constructed via the in situ reaction of layered zinc silicate nanosheets and Li. The consecutive Li+ -conductors can promote the desolvation process of solvated-Li+ and regulate the transfer of lithium ions. The nonconsecutive lithiophilic metals are polarized by the internal electric field to boost the transfer of lithium ions, and lower the nucleation barrier. Therefore, a low polarization of ≈50 mV for 750 h at 2.0 mA cm-2 in symmetric cells, and a high capacity retention of 99.2 % in full cells with a high lithium iron phosphate areal loading of ≈13 mg cm-2 are achieved. This work offers new sights to develop advanced alkali metal anodes for efficient energy storage.

4.
Guang Pu Xue Yu Guang Pu Fen Xi ; 37(1): 172-6, 2017 01.
Artículo en Chino | MEDLINE | ID: mdl-30196582

RESUMEN

It is important to understand heat loss from human head because human head produces much heat for its high metabolism, it also functions as a heat radiator to keep body heat balance. Heat loss from human head is closely related to its skin temperature. Therefore, skin surface temperature of human head changes with ambient temperature is studied. In this research, several positions were sampled and the advanced infrared detectors (the infrared thermal imager and the infrared thermometer) were used as tools for measurement. For the sake of comparison, the young volunteers were grouped into the boys team and the girls team. Results showed that, firstly, between the groups, there was only a little difference in that girls' head temperature was a little higher; secondly, head temperature of either girls or boys rises with air temperature till about 30 ℃; and thirdly, exercise has only a little effect on the head temperature variation. This research is practical for further investigation on head heat flow and referential for health diagnosing by comparing the data recorded in this experiment.


Asunto(s)
Temperatura Cutánea , Regulación de la Temperatura Corporal , Ejercicio Físico , Femenino , Humanos , Rayos Infrarrojos , Temperatura
5.
Biomed Rep ; 5(4): 413-416, 2016 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-27699007

RESUMEN

Epilepsy is a common neurodegenerative disease with an increasing morbidity. Clinical treatment of epilepsy includes symptomatic treatment, etiological treatment, surgery and prevention. The aim of the present study was to determine the effects of antiepileptic drugs (AEDs) on serum folate and vitamin B12 in various epileptic patients, and to examine the correlation between these effects and secondary cerebrovascular events. A total of 68 epileptic patients, diagnosed between May 2012 and May 2014, were included in the present study. The study included 8 cases of autonomic seizures, 10 cases of absence seizures, 13 cases of complex partial seizures, 28 cases of generalized tonic-clonic seizures, and 9 cases of simple partial seizures. The patients received appropriate AED treatment according to the characteristics of epileptic seizure and the treatment guidance. The differences in the serum levels of folate and vitamin B12 in these patients, and the differences in the secondary cerebrovascular events in these patients after 1 year follow-up were analyzed. The difference in the AEDs used by various epileptic patients was statistically significant (P<0.05). The proportion of AED monotherapy in the autonomic seizure group and petit mal group was highest, and the proportion of two AED in combination with the psychomotor seizure, grand mal and simple partial seizure groups was highest. The serum levels of folate and vitamin B12 in these patients following treatment were significantly lower than those prior to treatment (P<0.05). The differences in the serum levels of folate and vitamin B12 in these groups following treatment were not statistically significant (P>0.05). The difference in the incidence of cerebrovascular events in these groups at follow up was not statistically significant (P>0.05). The multifactorial logistic regression analysis revealed that the serum levels of folate and vitamin B12 were the independent risk factors for epilepsy with secondary cerebrovascular events [folate: odds ratio (OR)=0.536, P=0.039; vitamin: OR=0.382, P=0.041]. In conclusion, various AEDs may decrease the serum levels of folate and vitamin B12 and affect the secondary cerebrovascular events in various epileptic patients. Thus, regular supplementation of folate and vitamin B12 may be an option.

6.
Rev Sci Instrum ; 86(9): 093701, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26429442

RESUMEN

Blind source separation (BSS) based x-ray image denoising from an image sequence is proposed. Without priori knowledge, the useful image signal can be separated from an x-ray image sequence, for original images are supposed as different combinations of stable image signal and random image noise. The BSS algorithms such as fixed-point independent component analysis and second-order statistics singular value decomposition are used and compared with multi-frame averaging which is a common algorithm for improving image's signal-to-noise ratio (SNR). Denoising performance is evaluated in SNR, standard deviation, entropy, and runtime. Analysis indicates that BSS is applicable to image denoising; the denoised image's quality will get better when more frames are included in an x-ray image sequence, but it will cost more time; there should be trade-off between denoising performance and runtime, which means that the number of frames included in an image sequence is enough.

7.
Guang Pu Xue Yu Guang Pu Fen Xi ; 35(5): 1316-9, 2015 May.
Artículo en Chino | MEDLINE | ID: mdl-26415452

RESUMEN

To optimize color rendering of mixed-color LEDs, the Gaussian model was used to analyze the color-mixed LED's spectrum power distribution. The peak wavelength "λm", spectral half width "Δλ" and amplitude "A" were basic parameters for optimizing color rendering R9, which is very important for objects to be colorful and vivid under the white light LED's'illuminating. The typical methods for color mixing were used to get white light LEDs. Result was that to get the satisfied color rendering index, one of the color primaries should be certain and then other color primaries would be analyzed through changing three basic parameters step by step. It was concluded that the analysis in this paper would be referential to optimize the color-mixed white LED's color rendering.

8.
Guang Pu Xue Yu Guang Pu Fen Xi ; 35(3): 825-8, 2015 Mar.
Artículo en Chino | MEDLINE | ID: mdl-26117905

RESUMEN

X-ray medical image can examine diseased tissue of patients and has important reference value for medical diagnosis. With the problems that traditional X-ray images have noise, poor level sense and blocked aliasing organs, this paper proposes a method for the introduction of multi-spectrum X-ray imaging and independent component analysis (ICA) algorithm to separate the target object. Firstly image de-noising preprocessing ensures the accuracy of target extraction based on independent component analysis and sparse code shrinkage. Then according to the main proportion of organ in the images, aliasing thickness matrix of each pixel was isolated. Finally independent component analysis obtains convergence matrix to reconstruct the target object with blind separation theory. In the ICA algorithm, it found that when the number is more than 40, the target objects separate successfully with the aid of subjective evaluation standard. And when the amplitudes of the scale are in the [25, 45] interval, the target images have high contrast and less distortion. The three-dimensional figure of Peak signal to noise ratio (PSNR) shows that the different convergence times and amplitudes have a greater influence on image quality. The contrast and edge information of experimental images achieve better effects with the convergence times 85 and amplitudes 35 in the ICA algorithm.


Asunto(s)
Algoritmos , Procesamiento de Imagen Asistido por Computador , Radiografía/métodos , Humanos , Valores de Referencia , Relación Señal-Ruido , Rayos X
9.
J Hazard Mater ; 154(1-3): 476-83, 2008 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-18054157

RESUMEN

Qualitative theoretical analysis about air pressure influence upon the gas concentration of a fire plume was given, different scale n-heptane pool fires were conducted in a small and a standard compartment room in Lhasa and Hefei, respectively. The experimental results show that, in Lhasa, the average mass burning rates in the small room and the standard room both decrease, burning time increases at about 53% in small room and 45% in standard room more than in Hefei. Whereas for maximum changes of CO concentration, in the small room, in Lhasa, CO concentrations reach about twice bigger peak values at larger increase rates than in Hefei. While in the standard room, in Lhasa and Hefei, there are no significant changes for CO concentration, which agrees well with the theoretical analysis results.


Asunto(s)
Monóxido de Carbono/análisis , Incendios , Heptanos , Presión Atmosférica , Oxígeno/análisis
10.
Guang Pu Xue Yu Guang Pu Fen Xi ; 27(3): 610-3, 2007 Mar.
Artículo en Chino | MEDLINE | ID: mdl-17554935

RESUMEN

By combining X-ray imaging technology and low light level imaging technology, the authors' research group designed the novel combined X-ray image intensifier. Different from the imported conventional one, it is an X-ray screen lens coupled with a brightness intensifier, and is a non-vacuum device. In this paper, the novel combined X-ray image intensifier is described in terms of its structure, imaging principle and imaging performance, and the comparisons of the structure, imaging principle and imaging performance between the novel combined one and the conventional one are given in detail. It is clear that the conventional medical tube is a little better than the novel combined one in imaging performance, whereas the novel combined one has a very high cost effectiveness and the satisfied imaging performance, and moreover, the quality disparity between the novel combined one and the imported medical one is being shortened. The novel combined one meets the X-ray imaging standard in many science and research fields and is convenient to be accepted by the usual users and has wide application fields such as industrial detection, nondestructive test and airport security check.

11.
Guang Pu Xue Yu Guang Pu Fen Xi ; 25(7): 1162-4, 2005 Jul.
Artículo en Chino | MEDLINE | ID: mdl-16241082

RESUMEN

In the intelligent traffic system, the automatic recognition system of the car plate is an important development field. This system must satisfy the requirement of all-day long inspection. In the course of inspection, the lack of natural light(such as at night, in rainy day...) could be a problem, that is to say there could be backlighting problem, and this problem can be solved by using compensatory light. By now, the high-power floodlight has been adopted. Because of its own characteristics of the floodlight, the satisfied result cannot be obtained. In the present thesis, how to select the right light is analyzed, including car lights' spectra and visual response, and so on. The results of the practices are very satisfied.


Asunto(s)
Automóviles , Luz , Análisis Espectral/métodos , Ritmo Circadiano , Humanos , Iluminación , Procesamiento de Señales Asistido por Computador , Percepción Visual
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