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1.
Langmuir ; 39(40): 14384-14395, 2023 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-37770467

RESUMEN

The high content of nitrogen and sulfur-doped carbon dots (N, S-CDs) was designed to prevent the corrosion of X65 steel in an acidic medium. The corrosion-inhibiting abilities of related nanomaterials for X65 steel were acquired by electrochemical experiments, and the corroded products were investigated by FT-IR, XPS, and Raman analysis. The conclusions confirm that the N, S-CDs are a high-efficiency inhibitor. When the concentration is 200 mg/L, the inhibitive efficiency of X65 steel can reach up to 99.1% and it interacts with X65 steel through chemical and physical adsorption. Additionally, results from the spectroscopic studies show that the S-group is the main contributor to the chemical adsorption process.

2.
BMC Cancer ; 21(1): 355, 2021 Apr 06.
Artículo en Inglés | MEDLINE | ID: mdl-33823834

RESUMEN

BACKGROUND: The long non-coding (lnc) RNA activated by small nucleolar RNA host gene 16 (SNHG16), which has been reported to play a vital role in a number of different types of cancer, is a novel lncRNA. However, following an osteosarcoma (OS) study, the expression pattern, biological roles, clinical values and potential molecular mechanism of SNHG16 remain unclear. In the current study, we aimed to examine its expression and possible function in osteosarcoma (OS). METHOD: Cell proliferation was measured by colony formation assay and Cell Counting Kit-8 (CCK-8) in vitro, and xenograft transplantation assay in vivo. Meanwhile, we used transwell chambers to test cell migration and invasion was evaluated. Cell cycle and apoptosis was evaluated by flow cytometry assay. Immunoblotting and qPCR analysis was carried out to detect protein and gene expression, respectively. Luciferase reporter assay was used to predict the potential downstream genes. RESULTS: The present study demonstrated that SNHG16 is highly expressed in both the tissues of patients with OS, as well as OS cell lines, and its expression level was positively correlated with clinical stage and poor overall survival. Functional assays revealed that the depletion of SNHG16 inhibits OS growth, OS cell progression and promotes apoptosis both in vivo and in vitro. In addition, the present study revealed that microRNA-1285-3p expression levels can be decreased by SNHG16 acting as a 'sponge', and that this pathway takes part in OS tumor growth in vivo, and OS cell proliferation, invasion, migration and apoptosis in vitro. CONCLUSIONS: The results from the present study demonstrate the role of lncRNA SNHG16 in OS progression, which is SNHG16 might exert oncogenic role in osteosarcoma (OS) by acting as a ceRNA of miR-1285-3p, and it may become a novel target in OS therapy.


Asunto(s)
MicroARNs/metabolismo , Osteosarcoma/genética , ARN Largo no Codificante/genética , Animales , Línea Celular Tumoral , Proliferación Celular , Progresión de la Enfermedad , Humanos , Masculino , Ratones , Ratones Desnudos , Transfección
3.
Phys Chem Chem Phys ; 22(8): 4592-4601, 2020 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-32048667

RESUMEN

In order to explore the effects of the structures of organic molecules on their performance and develop high-efficiency self-assembly monolayers (SAMs), two heterocycle-based indole compounds, namely FYBI and TYBI, have been synthesized by a simple route. Herein, we show that FYBI and TYBI can effectively self-assemble on a copper surface and form strong anti-corrosive monolayers to protect copper in acid medium. The compositions, morphologies, and thicknesses of the SAMs have been investigated by XPS, FTIR, SEM and ellipsometry analyses. The optimal self-assembly conditions and inhibition performance of the SAMs with O- or S-heterocycles have been studied by electrochemical tests. According to the results, TYBI displays more powerful inhibition performance than FYBI. Furthermore, the high-resolution XPS and quantum calculation results reveal that the S-heterocycle indole (TYBI) can readily donate electrons to the empty d orbital of Cu and form more robust, hydrophobic, and anti-corrosive SAMs than the O-heterocycle indole (FYBI). The inhibited corrosion is achieved by inhibiting the generation of Cu2+. This systematic study on the performance of various heterocycle-based organic compounds gives a fresh perspective for forming SAMs with certain characteristics, such as anti-corrosion ability or super-hydrophobicity.

4.
Am J Ther ; 24(3): e290-e297, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-26035033

RESUMEN

There are several therapeutic strategies available for the treatment of an acute gout attack and the prevention of recurrent gout flares, and they include nonsteroid anti-inflammatory drugs. This prospective study was aimed at evaluating the efficiency and safety of diacerein in combination with febuxostat on urate control, global assessments of disease activity, self-monitored gouty acute flare times, inflammatory markers, and clinical symptoms associated with their life quantity in patients with refractory gout. A total of 64 patients with refractory gout were sequentially recruited and prescribed with oral febuxostat alone or febuxostat plus diacerein daily for 12 weeks. The intensity of joint pain, numbers of acute flare, disease activity and the levels of serum amyloid A, mature IL-1ß, IL-18, C-reactive protein, and urate in individual subjects were routine analyzed. In comparison with that treatment with febuxostat alone, treatment with both drugs for 12 weeks had a better therapeutic effect on reducing the values of visual analog scales, acute flares, and healthy assessment questionnaire scores in these gout patients. Furthermore, treatment with both drugs also significantly reduced the mean daily dose of etoricoxib and the levels of serum IL-1ß and serum amyloid A. There was no significant difference in the frequency of patients with adverse effect between these 2 groups of patients. In conclusion, combination of diacerein and febuxostat had better therapeutic effect on reducing acute gout flares, inflammation, and clinical symptoms in patients with refractory gout.


Asunto(s)
Antraquinonas/administración & dosificación , Febuxostat/administración & dosificación , Supresores de la Gota/administración & dosificación , Gota/tratamiento farmacológico , Adulto , Antraquinonas/efectos adversos , Antraquinonas/farmacología , Antiinflamatorios/administración & dosificación , Antiinflamatorios/efectos adversos , Antiinflamatorios/farmacología , Proteína C-Reactiva/metabolismo , Estudios de Casos y Controles , Quimioterapia Combinada , Etoricoxib , Febuxostat/efectos adversos , Febuxostat/farmacología , Femenino , Estudios de Seguimiento , Gota/fisiopatología , Supresores de la Gota/efectos adversos , Supresores de la Gota/farmacología , Humanos , Interleucina-18/sangre , Interleucina-1beta/sangre , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Piridinas/administración & dosificación , Sulfonas/administración & dosificación , Resultado del Tratamiento , Ácido Úrico/metabolismo
5.
Small ; 11(31): 3782-8, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25865036

RESUMEN

Antibody-conjugated nanomaterials have attracted much attention because of their applications in nanomedicine and nanotheranostics, and amplification of detection signals. For many of these applications, the nanoconjugates must bind with a cell membrane receptor (antigen) specifically before entering the cells and reaching the final target, which is thus important but not well understood. Here, a plasmonic imaging study of the binding kinetics of antibody-conjugated gold nanoparticles with antigen-expressing cells is presented, and the results are compared with that of the nanoparticle-free antibody. It is found that the nanoconjugates can significantly affect the binding kinetics compared with free antibody molecules, depending on the density of the antibody conjugated on the nanoparticles, and expressing level of the antigen on the cell membrane. The results are analyzed in terms of a transition from monovalent binding model to a bivalent binding model when the conjugation density and expressing level increase. These findings help optimize the design of functional nanomaterials for drug delivery and correct interpretation of data obtained with nanoparticle signal amplification.


Asunto(s)
Anticuerpos Monoclonales/química , Oro/química , Nanopartículas del Metal/química , Línea Celular , Línea Celular Tumoral , Membrana Celular/metabolismo , Sistemas de Liberación de Medicamentos , Humanos , Cinética , Nanoconjugados/química , Nanomedicina , Nanoestructuras/química , Perfusión , Unión Proteica , Receptor ErbB-2/química , Propiedades de Superficie , Trastuzumab/química
6.
J Fluoresc ; 25(6): 1559-66, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26344376

RESUMEN

A series of new asymmetric chromophores containing aromatic substituents and possessing the excellent π-extension in space were prepared through multi-steps routes. One-photon and two-photon spectral properties of these new chromophores could be tuned by these substituents finely and simultaneously. The linear correlation of the wave numbers of the one-photon absorption and emission maxima to Hammett parameters of these substituents was presented. Near infrared two-photon absorption emission integrated areas of the target chromophores were correlated linearly to Hammett constants of these substituted groups.


Asunto(s)
Colorantes Fluorescentes/química , Hidrocarburos Aromáticos/química , Fotones , Modelos Lineales , Fenómenos Ópticos , Espectrometría de Fluorescencia
7.
Nanotechnology ; 25(44): 445704, 2014 Nov 07.
Artículo en Inglés | MEDLINE | ID: mdl-25319748

RESUMEN

Despite various electrochemically active materials, such as metals, metal oxides and sulfides, which have been widely utilized for lithium storage, these materials still encounter unsatisfied electrochemical performances including low reversible capacity, slow charge-discharge capability and poor cycle performance. Here, we demonstrate a simple approach to fabricate one-dimensional CoO nanowires vertically aligned on a 3D graphene network (denoted as a 3D CoO/graphene network) via a wet chemistry process. The resulting CoO/graphene network possesses an interconnected graphene network, hierarchical pores and a carpet-like structure. This unique network can (1) facilitate the easy access of the electrolyte, (2) prevent the aggregation of CoO nanowires, (3) accommodate the volume change of CoO during the cycle processes, (4) maintain a high electrical conductivity for the overall electrode and (5) give rise to a high content of CoO in the composite (∼92 wt%). As a result, the 3D CoO/graphene network can be directly used as an anode material without any binder or conductive additives for lithium storage, and it exhibits a high capacity of 857 mAh g(-1), an excellent rate capability and good cycle performance. We believe that such a simple but efficient protocol will provide a new pathway for the fabrication of various 3D metal or metal oxide-graphene networks for wide applications in such fields as energy storage, sensors and catalysts.

8.
Nano Lett ; 13(11): 5408-13, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24148090

RESUMEN

Various two-dimensional (2D) materials have recently attracted great attention owing to their unique properties and wide application potential in electronics, catalysis, energy storage, and conversion. However, large-scale production of ultrathin sheets and functional nanosheets remains a scientific and engineering challenge. Here we demonstrate an efficient approach for large-scale production of V2O5 nanosheets having a thickness of 4 nm and utilization as building blocks for constructing 3D architectures via a freeze-drying process. The resulting highly flexible V2O5 structures possess a surface area of 133 m(2) g(-1), ultrathin walls, and multilevel pores. Such unique features are favorable for providing easy access of the electrolyte to the structure when they are used as a supercapacitor electrode, and they also provide a large electroactive surface that advantageous in energy storage applications. As a consequence, a high specific capacitance of 451 F g(-1) is achieved in a neutral aqueous Na2SO4 electrolyte as the 3D architectures are utilized for energy storage. Remarkably, the capacitance retention after 4000 cycles is more than 90%, and the energy density is up to 107 W·h·kg(-1) at a high power density of 9.4 kW kg(-1).


Asunto(s)
Capacidad Eléctrica , Nanoestructuras/química , Compuestos de Vanadio/química , Electrodos , Electrólitos , Diseño de Equipo , Agua/química
9.
Small ; 9(17): 2905-10, 2013 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-23589515

RESUMEN

Micrometer-sized electrochemical capacitors have recently attracted attention due to their possible applications in micro-electronic devices. Here, a new approach to large-scale fabrication of high-capacitance, two-dimensional MoS2 film-based micro-supercapacitors is demonstrated via simple and low-cost spray painting of MoS2 nanosheets on Si/SiO2 chip and subsequent laser patterning. The obtained micro-supercapacitors are well defined by ten interdigitated electrodes (five electrodes per polarity) with 4.5 mm length, 820 µm wide for each electrode, 200 µm spacing between two electrodes and the thickness of electrode is ∼0.45 µm. The optimum MoS2 -based micro-supercapacitor exhibits excellent electrochemical performance for energy storage with aqueous electrolytes, with a high area capacitance of 8 mF cm(-2) (volumetric capacitance of 178 F cm(-3) ) and excellent cyclic performance, superior to reported graphene-based micro-supercapacitors. This strategy could provide a good opportunity to develop various micro-/nanosized energy storage devices to satisfy the requirements of portable, flexible, and transparent micro-electronic devices.

10.
Polymers (Basel) ; 15(23)2023 Nov 22.
Artículo en Inglés | MEDLINE | ID: mdl-38231934

RESUMEN

High-performance flexible actuators, integral components of soft robotics, hold promise for advancing applications in safe human-robot interactions, healthcare, and various other fields. Notable among these actuators are flexible electrochemical systems, recognized for their merits in low-voltage manipulation, rapid response speed, and cost-effectiveness. However, the optimization of output strain, response speed, and stability presents a significant challenge in this domain. Despite the application of diverse electrochemically active materials to enhance actuation performance, a critical need persists for corresponding electrical-mechanical models to comprehensively grasp actuation mechanisms. In this study, we introduce a novel electrochemical actuator that utilizes conductive polymer ionogel as active electrodes. This ionogel exhibits exceptional properties, including high conductivity, flexibility, and electrochemical activity. Our electrochemical actuators exhibit noteworthy bending strain capabilities and rapid response rates, achieving frequencies up to 10 Hz at a modest voltage of 1 V. An analytical model integrating ion migration and dynamic processes has been established to elucidate actuator behavior. Simulation results highlight that electrodes characterized by low resistance and high capacitance are optimal for simultaneous enhancement of bending strain and blocking force. However, the augmentation of Young's modulus, while increasing blocking force, compromises bending strain. Furthermore, a larger aspect ratio proves beneficial for unidirectional stress output, leading to increased bending strain, while actuator blocking force diminishes with greater length. These findings underscore the intricate interplay between material properties and dimensions in optimizing the performance of flexible electrochemical actuators. This work provides important practical and theoretical guidance for the manufacture of high-performance flexible actuators and the search for new smart materials.

11.
Materials (Basel) ; 16(2)2023 Jan 12.
Artículo en Inglés | MEDLINE | ID: mdl-36676509

RESUMEN

As a wide bandgap semiconductor material, silicon carbide has promising prospects for application. However, its commercial production size is currently 6 inches, and the difficulty in preparing larger single crystals increases exponentially with size increasing. Large-size single crystal growth is faced with the enormous problem of radial growth conditions deteriorating. Based on simulation tools, the physical field of 8-inch crystal growth is modeled and studied. By introducing the design of the seed cavity, the radial temperature difference in the seed crystal surface is reduced by 88% from 93 K of a basic scheme to 11 K, and the thermal field conditions with uniform radial temperature and moderate temperature gradient are obtained. Meanwhile, the effects of different processing conditions and relative positions of key structures on the surface temperature and axial temperature gradients of the seed crystals are analyzed in terms of new thermal field design, including induction power, frequency, diameter and height of coils, the distance between raw materials and the seed crystal. Meanwhiles, better process conditions and relative positions under experimental conditions are obtained. Based on the optimized conditions, the thermal field verification under seedless conditions is carried out, discovering that the single crystal deposition rate is 90% of that of polycrystalline deposition under the experimental conditions. Meanwhile, an 8-inch polycrystalline with 9.6 mm uniform deposition was successfully obtained after 120 h crystal growth, whose convexity is reduced from 13 mm to 6.4 mm compared with the original scheme. The results indicate that the optimized conditions can be used for single-crystal growth.

12.
Comput Intell Neurosci ; 2022: 3442610, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35747715

RESUMEN

The development of information technology has been deployed in almost all sectors and is making life easier. In this development, the sports sector has seen tremendous expansion. In traditional table tennis training, the coach and the players have to meet daily to take appropriate training for the game. This process is time-consuming in a complex environment, and it will have a significant impact on the reformation and development of table tennis training. The utilization of improved technologies can overcome this challenge by performing training of the game online with an intelligent wireless system with advanced training mechanisms. Carrying the traditional and heavier intelligent wireless devices will be difficult for the players. In this research, the fine-grained evaluation (FGE) system is incorporated into the deep learning model to analyze the player's body postures during the training and event sessions and make them develop after each session through online training in any circumstance. The proposed FGE was compared with the traditional statistical model, and it was observed that the proposed FGE had obtained higher precision and recall values of 70% and 98.9% than the statistical model.


Asunto(s)
Deportes , Tenis , Inteligencia Artificial , Modelos Estadísticos
13.
RSC Adv ; 12(31): 19936-19945, 2022 Jul 06.
Artículo en Inglés | MEDLINE | ID: mdl-35865196

RESUMEN

The excellent physical properties of SiC as an electronic material determine its important application prospects, especially in the new-energy industry, but the preparation of large-sized materials with high quality is not easy. Therefore, the physical fields in the growth process were modeled and studied with the help of the numerical simulation software Virtual Reactor, and its accuracy was verified by the agreement between morphology of the experimental crystal and the simulation. Additionally, the effects of thermal insulation adjustment of crystal growth thermal fields, application of seed crystals with different diameters, and shelter structure on the crystal growth process were also studied. By optimizing the crystal growth conditions, a nearly flat and slightly convex crystal growth interface was obtained successfully in our lab. Crystal quality was significantly improved, and a 6-inch SiC crystal with single polytype, high quality and low defects was successfully prepared.

14.
Materials (Basel) ; 15(22)2022 Nov 18.
Artículo en Inglés | MEDLINE | ID: mdl-36431674

RESUMEN

Silicon carbide (SiC) is a wide-bandgap (WBG) semiconductor material, and its preparation process has strict requirements on the purity of raw materials. A self-developed medium-frequency induction heating furnace was used to carry out powder heat treatment and purification experiments on SiC powder to improve the purity of the powder. Samples with 3.5N purity were analyzed using XRD and GDMS characterization methods. It was found that under conditions of high-temperature (2200 °C) and long-time (50 h) processing, the impurity removal effect was quite good, but the powder loss was as high as 53.42%. The powder loss during the low-temperature (less than 2050 °C) and short-time process was less than 1.5%, but the purification effect was not substantial. After a prolonged processing time, the purification effect of low-temperature heat treatment conditions was improved, but the powder loss was also increased to 30%. In contrast, segmented purification processing at a low temperature in the early stage and a high temperature in the later stage achieved a good purification effect. On the premise of maintaining the utilization rate of raw materials, a 5N-purity SiC source was successfully prepared. The test results show that the contents of free Si, free C and free oxygen impurities were reduced to less than 0.01%, and the contents of Al, B, Fe, Mg, Na, Ti and other impurities were less than 1.15 ppm, which is close to the ppb level.

15.
Front Surg ; 9: 938565, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36684312

RESUMEN

Background: Nontraumatic osteonecrosis of the femoral head (ONFH) can be corticosteroid-induced, alcohol-induced, and idiopathic ONFH (IONFH). Although corticosteroid- and alcohol-induced ONFH has been investigated extensively regarding its relationship with blood lipids and coagulation factor levels. However, the effect of blood lipid metabolism and coagulation function on IONFH has rarely been studied. Therefore, this study aimed to analyse the relationship of IONFH with blood lipid and coagulation indicators. Methods: Total 680 patients diagnosed with IONFH in our institution during January 2011-June 2019 who met the inclusion criteria composed the case group; 613 healthy persons who underwent physical examination at our institution during the same period composed the control group. Propensity scores were used for baseline feature matching, and two matching groups each with 450 patients were established. After the matching, blood lipid and coagulation factor levels of both groups were comparatively analysed. Results: The case group showed significantly higher total cholesterol (TC), triglyceride (TG), low-density lipoprotein (LDL) levels, low-density/high-density lipoprotein (LDL/HDL) ratio, and apolipoprotein B (Apo-B) levels than the control group (p < 0.05). Conversely, the HDL and apolipoprotein A (Apo-AI) levels in the case group were significantly lower than those in the control group (p < 0.05). Regarding coagulation indicators, the activated partial thromboplastin time and prothrombin time were lower in the case group than in the control group; however, the differences were insignificant (p > 0.05). Furthermore, fibrinogen (FIB) levels and thrombin time (TT) in the case group were higher than those in the control group. There were significant differences between the two groups only in terms of FIB levels (p < 0.05), while TT was not significantly different (p > 0.05). Conclusions: IONFH has strong associations with blood lipid metabolism and coagulation function, which provide an avenue for exploring the mechanism of IONFH.

16.
Materials (Basel) ; 16(1)2022 Dec 28.
Artículo en Inglés | MEDLINE | ID: mdl-36614620

RESUMEN

SiC substrates have outstanding advantages over traditional materials in power device application, and are mainly prepared by a physical vapor transport method (PVT). Whether the PVT furnace works by resistance heating or induction heating, both face the problem of the deterioration of growth conditions during a long-term process. The relative position of the thermal field directly affects the crystal growth conditions, but the law of specific influence and the change in physical environment inside the thermal field have not been made sufficiently clear and lack systematic research. Therefore, SiC single crystal growth, with different directions and rates in the direction of movement of the heating module, was modeled using a simulation method, and the law of variation of the physical field, including heat flux, temperature, powder porosity and growth rate parameters under different schemes, was analyzed. The study indicates that the decay of raw materials is the primary reason why growth conditions cannot be maintained. The results verified that different coils' modes of movement have different effects on the improvement or adjustment of SiC crystals' growth conditions. Under the same temperature control conditions, the coils' movement rates of 200 µm/h, 0, -200 µm/h and -400 µm/h correspond to the average growth rates of 140, 152, 165 and 172 µm/h, respectively. The results show that downward displacement of the coils is beneficial in compensating for the deterioration of growth conditions, but it is easier to form convex surfaces and is not conducive to expanding diameter growth. This also verifies that the desired crystal growth state can be obtained by adjusting the position of the thermal field.

17.
Rev Assoc Med Bras (1992) ; 68(5): 605-609, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35584482

RESUMEN

OBJECTIVE: The purpose of this study was to compare arterial stiffness and ultrasound indices in patients with and without chronic obstructive pulmonary disease. METHODS: In our retrospective study, 83 chronic obstructive pulmonary disease patients were assigned to the chronic obstructive pulmonary disease group and 80 healthy controls were enrolled. Pearson's correlation analysis software was used to analyze the correlation between arterial stiffness (including brachial ankle pulse wave velocity and ankle-brachial blood pressure index) and ultrasound index (including resistance index, pulsatility index, and intima-media thickness) at the carotid artery in chronic obstructive pulmonary disease patients. RESULTS: The ultrasound resistance index and pulsatility index level of chronic obstructive pulmonary disease group were lower than those of control group (t=6.326, 8.321, p<0.001). Compared with the control group, the chronic obstructive pulmonary disease group had higher intima-media thickness, total plaque area, and number of plaques (t=4.574, 7.493, 5.093, p<0.001). The arterial stiffness and ankle-brachial blood pressure index level in the chronic obstructive pulmonary disease group were higher than those in the control group (t=6.392, 5.109, p<0.001). Moreover, arterial stiffness in patients with chronic obstructive pulmonary disease was negatively correlated with the ankle-brachial blood pressure index, resistance index, and pulsatility index levels (p<0.05), while it is positively correlated with intima-media thickness, total plaque area, and number of plaques (p<0.05). CONCLUSION: Our results indicated that patients with chronic obstructive pulmonary disease have stiffer arteries compared with healthy control subjects; the ultrasound index could be used as an auxiliary indicator for clinical prediction of arterial stiffness, which is helpful to improve the accuracy of prediction and thus better guide clinical interventions in high-risk groups of chronic obstructive pulmonary disease in time.


Asunto(s)
Placa Aterosclerótica , Enfermedad Pulmonar Obstructiva Crónica , Rigidez Vascular , Índice Tobillo Braquial , Grosor Intima-Media Carotídeo , Humanos , Enfermedad Pulmonar Obstructiva Crónica/diagnóstico por imagen , Análisis de la Onda del Pulso , Estudios Retrospectivos
18.
J Colloid Interface Sci ; 607(Pt 1): 45-52, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34492352

RESUMEN

The property of an active material is not only influenced by its morphology and size, but also by its crystal phase. The present phase regulation of nickel sulfide is mainly achieved by controlling the participation of sulfur source in reaction. Thus, new perspectives direct at phase control need to be explored and supplemented. Herein, we proposed a novel coordination agent-dominated phase modulation strategy assisted by a hydrothermal process. It is found that increasing the amount of coordination agent can drove the phase transformation from the initial composite of ß-NiS/α-NiS/Ni3S4 to ß-NiS/α-NiS, and then to pure ß-NiS. The mechanism of phase regulation has been proposed, and the general application of this method has been demonstrated. By employing coordination agent, the size of resulted products is reduced, and the morphology is optimized. As a result, all of the pure ß-NiS electrodes indicate significantly enhanced specific capacity than the pristine ß-NiS/α-NiS/Ni3S4 composite. Notably, the sample synthesized with 3 mmol of urea (S11) shows uniform morphology and smallest size, and it gives a highest specific capacity of 223.8 mAh g-1 at 1 A g-1, almost 1.5 times of the original sample. The fabricated S11//rGO device delivers a high energy density of 56.6 Wh·kg-1 at a power density of 407.5 W·kg-1, and keeps an impressive capacity retention of 84% after 20,000 cycles. This work put forwards a new prospect for controlling the phase and composition of nickel sulfide based on coordination chemistry.

19.
J Colloid Interface Sci ; 609: 838-851, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34838315

RESUMEN

2,5-dihydroxy-1,4-dithiane (DDD) and 2,5-dimethy- [1.4] dithiane-2,5-diol (DTDD) two food flavors as environmentally-friendly inhibitors for Cu in 0.5 mol/L H2SO4 media were researched via theoretical calculation and experimental ways. Electrochemical measurement data showed that DDD and DTDD can exhibit high level anti-corrosion feature. The anti-corrosion efficiency of DDD and DTDD were as high as 99.6% and 98.9%, respectively. The atomic force microscope (AFM) and scanning electron microscope (SEM) tests showed that the Cu specimens were immersed in the H2SO4 with 5 mM DDD and DTDD for 30 h at the 298 K, and the Cu specimen surface was still smooth. Besides, the adsorption of DDD and DTDD at the interface of Cu/solution was comply with Langmuir adsorption. Theoretical calculation data showed that DDD exhibit more ascendant anti-corrosion feature than DTDD.


Asunto(s)
Cobre , Acero , Corrosión , Ácidos Sulfúricos
20.
J Fluoresc ; 21(1): 327-38, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-20945081

RESUMEN

This paper presents the molecular geometry optimization, two-photon absorption and electrochemistry of new dyes containing benzophenone part, including 4-(p-benzoyl-benzyloxy)yl-4'-nitro-diphenylethylene (C1), 4-[N-methyl-N-(2-(p-benzoyl-benzyloxy)yl-ethyl]-4'-nitro-diphenylethylene (C2), 4-[N-ethyl-N-(2-(p-benzoyl-benzyloxy)yl-ethyl]-4'-nitro-diphenylethylene (C3), and 4-N, N-bis[(2-(p-benzoyl-benzyloxy)yl-ethyl]-4'-nitro-diphenyl ethylene (C4). The molecular structural parameters show that the coplanarity of diphenylethylene moiety is diminished in the excited state for C1, while it is enhanced for C2, C3 and C4. The electron density distribution of frontier orbital suggests that the derivatives exhibit (π, π) transition with internal charge transfer character, and the extent of charge transfer of C2, C3 and C4 is larger than that of C1. The derivatives display remarkable two-photon absorption (TPA) induced up-converted emission under 800 nm Ti: Sapphire femtosecond laser excitation. The maximal TPA emission wavelength of C2, C3 and C4 is red-shifted with respect to that of C1. TPA cross sections of C2, C3 and C4 are larger than those of C1. The cyclic voltammograms and the fluorescence lifetimes of the derivatives were determined and discussed.


Asunto(s)
Benzoquinonas/química , Etilenos/química , Fotones , Electroquímica , Estructura Molecular , Espectrofotometría Ultravioleta
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