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1.
Nat Commun ; 12(1): 4876, 2021 08 12.
Artigo em Inglês | MEDLINE | ID: mdl-34385436

RESUMO

While the printed circuit board (PCB) has been widely considered as the building block of integrated electronics, the world is switching to pursue new ways of merging integrated electronic circuits with textiles to create flexible and wearable devices. Herein, as an alternative for PCB, we described a non-printed integrated-circuit textile (NIT) for biomedical and theranostic application via a weaving method. All the devices are built as fibers or interlaced nodes and woven into a deformable textile integrated circuit. Built on an electrochemical gating principle, the fiber-woven-type transistors exhibit superior bending or stretching robustness, and were woven as a textile logical computing module to distinguish different emergencies. A fiber-type sweat sensor was woven with strain and light sensors fibers for simultaneously monitoring body health and the environment. With a photo-rechargeable energy textile based on a detailed power consumption analysis, the woven circuit textile is completely self-powered and capable of both wireless biomedical monitoring and early warning. The NIT could be used as a 24/7 private AI "nurse" for routine healthcare, diabetes monitoring, or emergencies such as hypoglycemia, metabolic alkalosis, and even COVID-19 patient care, a potential future on-body AI hardware and possibly a forerunner to fabric-like computers.


Assuntos
Técnicas Biossensoriais/instrumentação , Medicina de Precisão/instrumentação , Têxteis , Dispositivos Eletrônicos Vestíveis , Tecnologia sem Fio/instrumentação , Técnicas Biossensoriais/métodos , COVID-19/diagnóstico , COVID-19/prevenção & controle , COVID-19/virologia , Desenho de Equipamento , Humanos , Monitorização Fisiológica/instrumentação , Monitorização Fisiológica/métodos , Medicina de Precisão/métodos , SARS-CoV-2/fisiologia , Suor/fisiologia
2.
ACS Omega ; 5(35): 22652-22660, 2020 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-32923825

RESUMO

To expand the application of p-n heterojunction NiO-SnO2 ceramic materials from gas sensors and photoelectrocatalysts to oxygen-evolution reaction (OER) catalysts, we fabricated two NiO-SnO2 ceramics on a Ti plate (NSCTs) using a simple layer-by-layer method. The prepared NSCTs (NSCT-480 and NSCT-600) were characterized and analyzed by scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), diffuse reflectance ultraviolet-visible spectroscopy (DRUV-vis), and X-ray photoelectron spectroscopy (XPS). The OER activity and stability were measured by linear sweep voltammetry, cyclic voltammetry, chronoamperometry, amperometric i-t curve, and chronopotentiometry in a 1.0 mol/L NaOH solution at normal temperature and pressure. After 500 cycles, the lower overpotential (η = 194 mV at 1 mA/cm2) indicated that NSCT-600 offered adequate performance as an OER electrocatalyst. Moreover, the changes observed with cyclic voltammetry, SEM, XRD, and XPS during the OER test revealed that the redox cycle of Ni2+/Ni3+, morphology, and crystal faces of NiO and SnO2 were three critical factors. The data proved that the NiO-SnO2 ceramic is a stable OER electrocatalyst. The results of this study will provide a guide for the design and fabrication of p-n heterojunction metal-oxide ceramic electrocatalysts with a high OER performance.

3.
Environ Technol ; : 1-12, 2020 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-32436434

RESUMO

In industrial electrolytic manganese metal process, the energy consumption closely related to the electrolysis of cathode and anode. The effect of Cl- concentration on electrochemical oscillation at the anode of the electrolytic manganese metal cell was investigated. The results showed that the electrochemical oscillation at the anode was inhibited by Cl-, and the amplitude and frequency of the electrochemical oscillation decreased as the increase of Cl- concentration. When the concentration of Cl- was 2.68 g/L, the cathode and anode electrodes could be effectively activated, and the manganese current efficiency reached its minimum, correspondingly, the power consumption reached its maximum. In addition, the presence of the chloride reduced the production of MnO2 at the anode surface. ClO4- and free ions formed insoluble amorphous structures on the surface of the anode with the increase in reaction time and chloride ion concentration, and the insoluble amorphous structures prevented further generation of MnO2. Thus, electrolytic manganese metal energy consumption decreased.

4.
ACS Omega ; 5(15): 8777-8783, 2020 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-32337439

RESUMO

Oxidative-alkaline leaching of vanadium from vanadium-chromium-reducing residues with K2Cr2O7 was investigated in this paper. The effects of processing parameters including dosage of NaOH, dosage of K2Cr2O7, reaction time, and reaction temperature on the leaching efficiency of vanadium were studied. The results simulated by response surface methodology indicated that vanadium leaching was affected significantly by the dosage of K2Cr2O7 and NaOH, and the processing parameters that affected the leaching efficiency of vanadium followed the order m(NaOH)/m(residue) > m(K2Cr2O7)/sssssm(residue) > reaction temperature > reaction time. The leaching efficiency of vanadium was up to 99.92% under optimal conditions: reaction temperature of 90 °C, reaction time of 60 min, liquid-to-solid ratio of 5:1 mL g-1, m(K2Cr2O7)/m(residue) = 0.10, and m(NaOH)/m(residue) = 0.30. The kinetics analysis indicated that diffusion through the product layer was the controlling step and the apparent activation energy for vanadium leaching was calculated to be 58.275 kJ·mol-1.

5.
ACS Appl Mater Interfaces ; 12(3): 3654-3660, 2020 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-31880147

RESUMO

To provide a light and breathable self-charging wearable power source adaptable for various weather conditions and body movements, couching embroidery has been proposed as an industrially scalable electrode-to-device assembling strategy, rather than a decorative textile pattern making process. Various types of cable electrodes and device units with a large size and shape difference were directly and reliably assembled on a light and soft tulle to form either photovoltaic or battery devices, which can be further integrated following any irregular pattern and any electrical connection design. Under sunlight, a transparent tulle as a glove or scarf can be charged up at a power of 10 W/m2, and then maintain stable power output in the dark for various weather and body moving conditions, including bending, twisting, hand-stretching, wind blowing, and water washing. Our approaches not only simplified the fabrication of integrated fabric-type energy devices but also improved the structural and functional design flexibility of a portable electronic power source, especially for summer wearing applications.

6.
Water Sci Technol ; 79(2): 366-374, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30865608

RESUMO

Many technologies have been proposed to oxidize chromium, such as roasting-water leaching technology and hydrometallurgical methods such as pressure oxidative leaching coupled with oxygen, ozone, permanganate and ferrate, but the problems associated with the high temperature, low overall resource utilization efficiency, high energy consumption, and the environmental pollution, still remain unsolved. This paper focuses on the oxidation process of chromium (III) with hydrogen peroxide (H2O2) in an alkaline medium. The effect of parameters including dosage of H2O2, dosage of NaOH, reaction time, reaction temperature and stirring rate on the oxidation efficiency of chromium were investigated. The oxidation efficiency was significantly affected by the dosage of H2O2 and NaOH, reaction time and reaction temperature took second place; last was the stirring rate. Oxidation efficiency was nearly 100% under the optimal conditions: volume ratio of H2O2 to mass of Cr2(SO4)3 of 2.4 mL/g, mass ratio of NaOH to Cr2(SO4)3 0.6 g/g, reaction time of 90 min, reaction temperature of 90 °C and stirring rate of 500 rpm.


Assuntos
Cromo/química , Modelos Químicos , Poluentes Químicos da Água/química , Cromo/análise , Peróxido de Hidrogênio/química , Oxirredução , Poluentes Químicos da Água/análise
7.
ISA Trans ; 90: 268-277, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30732993

RESUMO

The analysis of fluid flow signals and the characterization of fluid flow behavior are of great importance for two-phase flow studies. In this work, the fractional Fourier transform (FRFT), which was based on the optimum order calculated by stepping search method, was proposed to extract the characteristics of fluid flow signals. Meanwhile, the largest Lyapunov exponent (LLE), which is an indication of the chaotic degree of mixing process, was adopted to quantify fluid flow behavior. The maximum amplitude (MA) and LLE value were taken together to inquire into the relationship between the characteristics of fluid flow signals and the characterization of fluid flow behavior. In addition, differences between the two adjacent values (AD) and the maximum differences (MD) are employed to further analyze the differences in behavioral characterization with MA and LLE. The results show that the MA value performs the same increasing trend as the LLE value when the gas flow rate and agitation speed increase. AD and MD values of the MA are one to two orders of magnitude greater than those of the LLE. The eigenvalues (MA) solved by the FRFT method is facilitates capturing small changes owing to changes in external conditions. These findings can provide new ideas for the extraction and characterization of fluid flow behavior.

8.
J Colloid Interface Sci ; 542: 451-459, 2019 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-30771639

RESUMO

Hydrogen is one of the most clean energy carriers because water is only the product of its combustion. The electrolysis of ammonia is expected to offer an attractive alternative to water electrolysis for the production of hydrogen because of the lower thermodynamic energy. However, the synthesis and utilization of high-performance Pt electrocatalysts have encountered challenges related to instability and hydroxyl ion sensitivity. To address these issues, we developed PtSnOx-based nanoparticles that maintained high electrocatalytic activity and stability for the decomposition of aqueous ammonia to generate hydrogen under native pH conditions which means the acidity/alkalinity is not adjusted. FT-IR, XRD, and XPS evidence showed PtSnOx was a tri-functionalised electrocatalyst. That is to say, the spherical SnOx nanoparticles assisted ammonia adsorption and activation, which were accompanied by a hydrogen adsorption on PtSnOx and hydrogen transfer along the SnOH bond over the electrocatalyst. According to these data of FT-IR, XRD, and XPS before and after reaction, a possible mechanism for the decomposition of aqueous ammonia to produce hydrogen was proposed. This study could pave the way to prospective routes for the selective oxidation of the NH bond to generate hydrogen under mild conditions.

9.
ACS Appl Mater Interfaces ; 10(36): 30819-30826, 2018 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-30124283

RESUMO

Enormous interests have been attracted on exploiting interfacial triboelectric effects for sensor and energy applications but immensely limited by the inefficient liquid-solid electrification in terms of immersed applications in fluid. Here, we have presented a flexible self-powered all-in-one fluid sensor textile, for simultaneously monitoring the velocity, acceleration, and chemical composition based on an enhanced liquid-solid triboelectric effect. The textile was woven from flexible dendritic cable electrodes surrounded by arrays of micrometal dendrites, which could be further coated with a layer of polytetrafluoroethylene nanofibers. Even when completely immersed in the fluid, the textile can efficiently output a combined electric signal for parsing the velocity, acceleration, and chemical composition information. Furthermore, a textile of 6 cm2 can charge a commercialized capacitor to 1 V within 80 s by harvesting flow energy on the liquid/solid interface, showing a potential use as the power supply of a signal-processing circuit. It has proposed a promising fluid sensor without extra power cables, for alerting possible leakage or blockage inside chemical and petroleum pipelines.

10.
Sci Rep ; 8(1): 426, 2018 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-29323339

RESUMO

Hydrogen peroxide as an oxidant was applied in leaching of vanadium and chromium in concentrated NaOH solution. Under the optimal reaction conditions (the liquid to solid ratio of 4.0 ml/g, residue particle size of <200 mesh, the mass ratio of NaOH-to-residue of 1.0 g/g, the volume ratio of H2O2-to-residue of 1.2 ml/g, reaction temperature of 90 °C and reaction time of 120 min), the leaching efficiency of vanadium and chromium could reach up to 98.60% and 86.49%, respectively. Compared with the current liquid-phase oxidation technologies, the reaction temperature was 90-310 °C lower, and the NaOH concentration of the reaction medium is lower by more than 50 wt% (the mass ratio of NaOH-to-residue of 1.0 g/g equals to concentration of 20 wt%). The kinetics study revealed that leaching process of chromium and vanadium were interpreted with shrinking core model under chemical reaction control. The apparent activation energy of chromium and vanadium dissolution was 22.19 kJ/mol and 6.95 kJ/mol, respectively.

11.
Ecotoxicol Environ Saf ; 148: 220-227, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29055206

RESUMO

This study examined simultaneous stabilization and solidification (S/S) of Mn2+ and NH4+-N from electrolytic manganese residue (EMR) using MgO and different phosphate resource. The characteristics of EMR NH4+-N and Mn2+ S/S behavior, S/S mechanisms, leaching test and economic analysis, were investigated. The results show that the S/S efficiency of Mn2+ and NH4+-N could reach 91.58% and 99.98%, respectively, and the pH value is 8.75 when the molar ratio of Mg:P is 3:1 and the dose of PM (MgO and Na3PO4·12H2O) is 8wt%. In this process, Mn2+ could mainly be stabilized in the forms of Mn(H2PO4)2·2H2O, Mn3(PO4)2·3H2O, Mn(OH)2, and MnOOH, and NH4+-N in the form of NH4MgPO4·6H2O. Economic evaluation indicates that using PM process has a lower cost than HPM and HOM process for the S/S of Mn2+ and NH4+-N from EMR at the same stabilization agent dose. Leaching test values of all the measured metals are within the permitted level for the GB8978-1996 test suggested when the dose of PM, HPM and HOM is 8wt%.


Assuntos
Compostos de Amônio/química , Óxido de Magnésio/química , Manganês/química , Nitrogênio/química , Fosfatos/química , Eliminação de Resíduos/métodos , Eletrólise , Eletrólitos , Íons , Resíduos Sólidos/análise
12.
ACS Appl Mater Interfaces ; 9(46): 40207-40214, 2017 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-29087177

RESUMO

In the search for clothlike wearable energy-storage devices with both high energy density and high power density, metal fibers surrounded by micro metal dendrites, as current collectors, are either rooted inside a thick layer of carbon particles or wrapped with flowerlike nano NiO in a similar manner to the root or stem system of natural plants, to form dendritic cablelike negative or positive electrodes. These dendritic cable electrodes could be further combined or woven into flexible solid-type supercapacitive garland or fabric, together with cotton wires. Benefiting from the ultra large interface of the metal dendrites current collector, it can be charged up to 1.8 V, and give an energy density of 0.1408 mWh cm-2 and a power density of 3.01 mW cm-2, which is capable of directly starting a small electric car with a short and flexible piece of supercapacitor.

13.
Phys Chem Chem Phys ; 19(40): 27643-27650, 2017 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-28983548

RESUMO

Time-periodic phenomena widely exist in natural life sustaining systems but are rarely reported in highly efficient artificial electrochemical energy-harvesting systems. Herein, we observed for the first time the periodic oscillation reaction in organic-solvent dominated electrolytes that could be also derived from some electrochemical energy harvesting cells. Owing to different reaction activity and acidity in the organic solvent, the oscillation reaction could occur under milder pH conditions and exhibit better durability. Its influence on electric output and related differences from an aqueous B-Z reaction are discussed from a mechanism point of view. Our findings may contribute to smart self-oscillation materials and new strategies for highly efficient long-term energy harvesting.

14.
Environ Sci Pollut Res Int ; 24(27): 21761-21769, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28766147

RESUMO

Black rock series (BRS) is of great potential for their plenty of valued oxides which include vanadium, iron, alumina and silica oxides, etc. BRS was used for directly preparing of selective catalytic reduction (SCR) catalyst by modifying its surface texture with SiO2-TiO2 sols and regulating its catalytic active constituents with V2O5 and MoO3. Consequently, 90% NO removal ratio was obtained within 300-400 °C over the BRS-based catalyst. The structure and properties of the BRS-based catalyst were characterized by the techniques of N2 adsorption-desorption, X-ray diffraction (XRD), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), H2-temperature programmed reduction (H2-TPR), and NH3-temperature programmed desorption (NH3-TPD). The results revealed that the BRS-based catalyst possesses favorable properties for NO x removal, including highly dispersed active components, abundant surface-adsorbed oxygen Oα, well redox property, and numerous Brønsted acid sites. Particularly, the BRS-based catalyst exhibited considerable anti-poisoning performance compared with commercial TiO2-based catalyst. The former catalyst shows a NO conversion surpassing 80% from 300 to 400 °C for potassium poisoning, and a durability of SO2 and H2O exceeding 85% at temperatures from 300 to 450 °C.


Assuntos
Óxidos de Nitrogênio/química , Dióxido de Silício/química , Titânio/química , Adsorção , Amônia/química , Catálise , Molibdênio/química , Oxirredução , Óxidos/química , Oxigênio , Temperatura , Compostos de Vanádio/química , Difração de Raios X
15.
Water Sci Technol ; 75(10): 2316-2321, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28541939

RESUMO

Melamine, possessing three free amino groups and three aromatic nitrogen atoms in its molecule, has great potential as an adsorbent for metal ions. We investigated three impact factors of the adsorption process: the initial pH of the vanadium solution, contact time and reaction temperature. The adsorption kinetics could be accurately described by the pseudo-second-order kinetic model. Langmuir and Freundlich models fitted well with the experimental equilibrium data, and the maximal adsorption capacity was found to be 1,428.57 mg vanadium/g melamine, and the Freundlich model showed the adsorption is privilege type.


Assuntos
Modelos Químicos , Triazinas/química , Vanádio/química , Poluentes Químicos da Água/química , Adsorção , Concentração de Íons de Hidrogênio , Cinética , Temperatura , Termodinâmica
16.
Environ Technol ; 38(3): 370-376, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27249226

RESUMO

In this work, nitrite was developed to simultaneously remove manganese and ammonia nitrogen from wastewater by the electrochemical method. The characteristics of electrolytic reaction were observed via cyclic voltammograms. Moreover, the mole ratio of nitrite and ammonia nitrogen, voltage, and initial pH value, which affected the removal efficiency of ammonia nitrogen and manganese, were investigated. The results showed that the concentration of ammonia nitrogen in wastewater could be reduced from 120.2 to 6.0 mg L-1, and manganese could be simultaneously removed from 302.4 to 1.5 mg L-1 at initial pH of 8.0, the mole ratios of nitrite and ammonia nitrogen of 1.5:1, and voltage of 20 V direct current electrolysis for 4.0 h. XRD analysis showed that manganese dioxide was deposited on the anode, and manganese was mainly removed in the form of manganese hydroxide precipitation in the cathode chamber.


Assuntos
Amônia/química , Manganês/química , Nitritos/química , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/química , Eletrodos , Eletrólise , Concentração de Íons de Hidrogênio , Nitrogênio/química , Oxirredução , Águas Residuárias/química
17.
Environ Technol ; 38(16): 2077-2084, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27766915

RESUMO

In this study, an improved process for leaching manganese from electrolytic manganese residue (EMR) by electro-reduction was developed. The mechanisms of the electro-reduction leaching were investigated through X-ray diffraction, scanning electron microscopy, X-ray fluorescence, and Brunauer Emmett Teller. The results show that the electric field could change the surface charge distribution of EMR particles, and the high-valent manganese can be reduced by electric field. The leaching efficient of manganese reached 84.1% under the optimal leaching condition: 9.2 wt% H2SO4, current density of 25 mA/cm2, solid-to-liquid ratio of 1:5, and leaching time for 1 h. It is 37.9% higher than that attained without an electric field. Meanwhile, the manganese content in EMR decreased from 2.57% to 0.48%.


Assuntos
Eletrólise , Manganês , Eletrólitos , Íons , Difração de Raios X
18.
J Colloid Interface Sci ; 478: 172-80, 2016 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-27289432

RESUMO

Well-aligned ZnO nanorod arrays have been grown on metal-plated polymer fiber via a mild wet process in a newly-designed continuous reactor, aiming to provide wire-shaped photoanodes for wearable dye-sensitized solar cells. The growth conditions were systematically optimized with the help of computational flow-field simulation. The flow field in the reactor will not only affect the morphology of the ZnO nanorod⧹nanowire but also affect the pattern distribution of nanoarray on the electrode surface. Unlike the sectional structure from the traditional batch-type reactor, ZnO nanorods with finely-controlled length and uniform morphology could be grown from the continuous reactor. After optimization, the wire-shaped ZnO-type photoanode grown from the continuous reactor exhibited better photovoltaic performance than that from the traditional batch-type reactor.

19.
J Hazard Mater ; 317: 267-274, 2016 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-27295063

RESUMO

In this study, P-LGMgO (low-grade MgO and NaH2PO4·2H2O), P-CaO (CaO and NaH2PO4·2H2O), and P-MgCa (low-grade MgO, CaO and NaH2PO4·2H2O) were used for the solidification/stabilization (S/S) of electrolytic manganese residue (EMR). Relevant characteristics such as ammonia nitrogen and manganese stabilization behavior, unconfined compressive strength (UCS), probable S/S mechanisms, and EMR leaching test were investigated. The results demonstrate that using P-LGMgO had higher stabilization efficiency than P-CaO and P-MgCa for the S/S of EMR at the same stabilization agent dose. The stabilization efficiency of ammonia nitrogen and manganese in the EMR were 84.0% and 99.9%, respectively, and the UCS of EMR was 5.1MPa using P-LGMgO process after curing for 28 days when the molar ratio of Mg:P was 5:1 and dose of stabilization agent was 12wt%. In this process, ammonia nitrogen was stabilized by struvite (NH4MgPO4·6H2O), and manganese by bermanite (Mn3(PO4)2(OH)2·4H2O) and pyrochroite (Mn(OH)2). The leaching test results show that the values of all the measured metals on the 28th day were within the permitted level for the GB8978-1996 test suggested by China's environmental protection law and the concentration of ammonia nitrogen can be reduced from 504.0mgL(-1) to 76.6mgL(-1).

20.
Environ Sci Pollut Res Int ; 23(12): 12352-61, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26979316

RESUMO

The objective of this work was the immobilization of soluble manganese (Mn) and ammonium nitrogen (NH4 (+)-N) leached from electrolytic manganese residue (EMR). Immobilization of Mn was investigated via carbonation using carbon dioxide (CO2) and alkaline additives. NH4 (+)-N immobilization was evaluated via struvite precipitation using magnesium and phosphate sources. Results indicated that the immobilization efficiency of Mn using CO2 and quicklime (CaO) was higher than using CO2 and sodium hydroxide (NaOH). This higher efficiency was likely due to the slower release of OH(-) during CaO hydrolysis. The immobilization efficiency of Mn was >99.99 % at the CaO:EMR mass ratio of 0.05:1 for 20-min reaction time. The struvite precipitation of NH4 (+)-N was conducted in the carbonated EMR slurry and the immobilization efficiency was 89 % using MgCl2 · 6H2O + Na3PO4 · 12H2O at the Mg:P:N molar ratio of 1.5:1.5:1 for 90-min reaction time. A leaching test showed that the concentrations of Mn and NH4 (+)-N in the filtrate of the treated EMR were 0.2 and 9 mg/L, respectively. The combined immobilization of Mn and NH4 (+)-N was an effective pretreatment method in the harmless treatment of the EMR.


Assuntos
Compostos de Amônio/química , Manganês/química , Nitrogênio/química , Compostos de Cálcio/química , Eletrólise , Eletrólitos , Magnésio/química , Óxidos/química , Fosfatos/química , Estruvita/química
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