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1.
Sci Rep ; 14(1): 15735, 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38977721

RESUMO

The influence of precipitated nanophases on the mechanical properties of Fe-based amorphous nanocrystalline alloys is an urgent issue to be explored. Two amorphous nanocrystalline alloys, i.e., (Fe0.9Ni0.1)86B14 and (Fe0.7Ni0.3)86B14 containing nanophase of the body-centered cubic and face-centered cubic structures, respectively, were selected to investigate the effect of the structure and volume fraction of nanophase on their mechanical properties. The results of nanoindentation experiments and the calculation of the volume and size of the shear transition zone reveal that the two alloys show different mechanical properties. When the volume fraction of the nanophase in (Fe0.9Ni0.1)86B14 is larger than 50%, the elastic modulus is increased suddenly and the volume and size of the shear transition zone is decreased dramatically, while no dramatic change occurs in (Fe0.7Ni0.3)86B14. Moreover, it was found by using molecular dynamics simulations that the main reason for these abnormal mechanical properties is the change of cluster type in the system due to the incorporation of nanophases with different structures.

2.
Opt Lett ; 49(11): 2906-2909, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38824289

RESUMO

We theoretically present and experimentally validate a method to overlay the interference field (for making straight-line holographic gratings) with a real grating and a derived method to measure the lateral shift between two real gratings. The methods rely only on the real gratings' profile symmetry, and they are robust against variations of the real gratings' profile parameters and functional form.

3.
Appl Opt ; 62(35): 9414-9421, 2023 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-38108714

RESUMO

In this paper we present the design and fabrication of the reflection varied-line-space concave grating (VLSCG) for the project of CAFE (the Census of warm-hot intergalactic medium, Accretion, and Feedback Explorer), which aims to detect and map the warm-hot circumgalactic medium via OVI emission at 103.2 nm and 103.8 nm, using two off-Rowland-circle spectrograph channels. High diffraction efficiency at LUV is supposed for the VLSCG and an aperture ratio as small as $F/3.6$ is desired for a compact design. The gratings are fabricated by holographic lithography and ion beam etching techniques. We introduce an additional lens into the normal holographic exposing system to generate the varied-line-space grating patterns. Grooves with triangle profiles are obtained to increase the diffraction efficiency by oblique ion beam bombardment during the etching process. Finally, several VLSCGs with a central line density of 3300 lines/mm have been fabricated successfully. The measured results show that the groove efficiency reaches 51% at 106.4 nm and 31% at 127.4 nm. We imitated the working optical path of the spectrometer and used the ${-}{1}$ order of the VLSCG to measure the image near the exit slit. The results showed that the image of the point source has a vertical extent of 0.68 mm, and the aberrations have been corrected.

4.
Materials (Basel) ; 15(12)2022 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-35744111

RESUMO

Post-bond heat treatment (PBHT) is an effective way to improve the bonding quality of a brazed joint. Herein, brazing of a nickel-based single crystal superalloy is carried out using a Ni-Cr-Co-B-Si-Al-Ti-W-Mo filler alloy, and the microstructure and creep property of the brazed joint are systematically investigated using scanning electron microscopy (SEM), Thermo-Calc software, an electron probe micro-analyzer (EPMA), X-ray diffractometer, confocal scanning laser microscope (CSLM), and transmission electron microscopy (TEM). The results reveal that the as-prepared joint only consists of an isothermally solidified zone (ISZ) and an athermally solidified zone (ASZ), where the cubic γ' phase is observed in the ISZ, and skeleton-like M3B2, γ + γ' eutectic and reticular G phases are observed in the ASZ. Furthermore, the γ + γ' eutectic and G phases disappear and the M3B2 alters from a skeleton-like to block-like shape in the ASZ after PBHT. Meanwhile, some lath-like M3B2 phases are precipitated at the edge of the ISZ and several M3B2 phases are precipitated in the base metal, forming a new zone in the brazed joint, namely at the diffusion affected zone (DAZ). Owing to the removal of low melting point eutectics from the as-prepared joint, the creep life also increases from 188 h to 243 h after PBHT. The current work provides a method for the optimization of brazed joints based on the Ni-based single crystal superalloy.

5.
Appl Opt ; 60(31): 9925-9932, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34807182

RESUMO

The binary fused silica gratings (BFSGs) with high diffraction efficiency are presented for large astronomical ground-based telescopes. Calculations demonstrate that the BFSGs could obtain high diffraction efficiency in a wider wavelength range and angle of incident (AOI) range compared with volume phase holographic gratings. Several gratings with a size of 60mm×60mm have been fabricated by holographic lithography and reactive ion-beam etching technology. The measured peak diffraction efficiency reaches 94%, and results show that there are 130 nm wavelength bandwidth and 12° AOI bandwidth in which diffraction efficiency is higher than 70%. The stray light causes the diffraction efficiency to decrease by about 0.48%. All measurements have indicated good consistency with the simulation results.

6.
Environ Sci Pollut Res Int ; 28(35): 48038-48052, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33900554

RESUMO

Metallic glasses (MGs) with unique disordered atomic stacking structures exhibit excellent catalytic performance in wastewater treatment. The catalytic degradation of Orange II (AO II) aqueous solutions by four CuZr-based MG ribbons under such processing parameters as pH values, the dosage of ribbons, and temperature was investigated in this paper. The catalytic performance of the MG ribbons was characterized by using the degradation efficiency of the dye wastewater. The phase constituent, surface morphology, and chemical valence state of elements on the surface of MG ribbons before and after use were analyzed by X-ray diffraction (XRD), scanning electron microscopy (SEM), and X-ray photoelectron spectroscopy (XPS), respectively. The results indicate that the Cu46Zr42Al7Y5 MG ribbon has the best catalytic performance among the Cu46Zr47-xAl7Yx (x = 0, 1, 3, 5) MGs in the degradation process, and the dye in the wastewater can almost be completely decolorized within 60 min under the conditions of pH = 2, the dosage of ribbons being 1.8 g/L and water bath temperature of 313 K, with the degradation efficiency and chemical oxygen demand removal being 96.05% and 51.73%, respectively. Furthermore, the Cu46Zr42Al7Y5 MG ribbon still shows superior structural stability and degradation performance after repeated use, and the corrosion pits on the MG surface promote the physicochemical reaction between the wastewater and the ribbons.


Assuntos
Poluentes Químicos da Água , Purificação da Água , Análise da Demanda Biológica de Oxigênio , Catálise , Águas Residuárias , Poluentes Químicos da Água/análise
7.
Environ Sci Pollut Res Int ; 27(32): 40101-40108, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32656754

RESUMO

The oily wastewater was treated by electrocoagulation with Fe78Si9B13 amorphous ribbons as anode and graphite plates as cathode under such processing parameters as different pH values and current density, respectively. The degradation effect on the oily wastewater was characterized by chemical demand oxygen (COD), while the ribbons before and after using were analyzed by X-ray diffraction (XRD) and scanning electron microscope (SEM). The results indicate that under the conditions of pH = 3 and current density being 3.125 A/cm2, the optimal COD removal efficiency was obtained to be 73.22%. Compared with the ordinary crystalline iron plate, the COD removal efficiency of resultant wastewater degraded by the amorphous ribbons is more than doubled. Simultaneously, the Fe78Si9B13 amorphous ribbons exhibit good structural stability even after four cycles of using.


Assuntos
Águas Residuárias , Poluentes Químicos da Água , Análise da Demanda Biológica de Oxigênio , Eletrocoagulação , Eletrodos , Concentração de Íons de Hidrogênio , Resíduos Industriais/análise , Óleos , Eliminação de Resíduos Líquidos
8.
Waste Manag ; 103: 45-51, 2020 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-31865034

RESUMO

Until today, there are still many problems that must be solved through innovative research to make the recycling of spent lead-acid batteries and the separation of Pb-Sb alloy more environmentally friendly and energy-saving. In this paper, a novel method for regenerating lead paste, by vacuum reduction reaction coupling with separation of Pb-Sb alloy, was developed. In this process, antimony from Pb-Sb alloy is used to reduce desulfurized lead paste into lead under vacuum, while it is oxidized into volatile Sb2O3 as by-product. The results showed that direct recovery ratio of Pb from desulfurized lead paste reached 99.29% and Sb-content in Pb-Sb alloy decreased from 46% to 0.98% under following conditions: the mass ratio of desulfurized lead paste to Pb-Sb alloy of 1.50, residual gas pressure of 30 Pa, reduction temperature of 810 °C for 50 min. By this method, not only the lead paste can be recovered with high atom economy, but also the Pb-Sb alloy can be separated efficiently at zero cost and without "three wastes" generation. Therefore, this method is very useful for the recycling of spent lead-acid battery and the separation of Pb-Sb alloy.


Assuntos
Ligas , Chumbo , Fontes de Energia Elétrica , Reciclagem , Vácuo
9.
J Synchrotron Radiat ; 26(Pt 5): 1782-1789, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31490170

RESUMO

A fabrication method comprising near-field holography (NFH) with an electron beam lithography (EBL)-written phase mask was developed to fabricate soft X-ray varied-line-spacing gratings (VLSGs). An EBL-written phase mask with an area of 52 mm × 30 mm and a central line density greater than 3000 lines mm-1 was used. The introduction of the EBL-written phase mask substantially simplified the NFH optics for pattern transfer. The characterization of the groove density distribution and diffraction efficiency of the fabricated VLSGs indicates that the EBL-NFH method is feasible and promising for achieving high-accuracy groove density distributions with corresponding image properties. Vertical stray light is suppressed in the soft X-ray spectral range.

10.
J Hazard Mater ; 347: 334-340, 2018 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-29335215

RESUMO

With the wide application of lead acid battery, spent lead acid battery has become a serious problem to environmental protection and human health. Though spent battery can be a contaminant if not handled properly, it is also an important resource to obtain refined lead. Nowadays, the Sb-content in lead storage batteries is about 0.5-3 wt%, which is higher than the Sb-content in the crude lead. However, there are few reports about the process of removing antimony from high-antimony lead bullion. In this study, vacuum displacement reaction technology, a new process for removing antimony from high-antimony lead melts, was investigated. During this process, lead oxide was added to the system and antimony from lead melts was converted into antimony trioxide, which easily was evaporated under vacuum so that antimony was removed from lead melts. The experimental results demonstrated that Sb-content in lead melts decreased from 2.5% to 23 ppm under following conditions: mass ratio of PbO/lead bullion of 0.33, residual gas pressure of 30 Pa, melt temperature of 840 °C, reaction time of 60 min. The distillate gotten can be used as by-product to produce antimony white. Moreover, this study is of importance to recycling of waste lead storage batteries alloy.

11.
J Opt Soc Am A Opt Image Sci Vis ; 34(3): 308-313, 2017 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-28248373

RESUMO

The basic principle and method to generate structural color from the photoresist grating of the multilayer dielectric diffraction grating are introduced. Rigorous coupled-wave analysis is used for computation with the open software RCWA-1D. The relationships between the characteristics of the photoresist and the structural color are explained. This paper discusses the effect of light source characteristics on the duty cycle color resolution, indicating that TE polarization is better than TM polarization, and the FWHM should be sufficiently large with an optimized value for the incident angle.

12.
Analyst ; 141(13): 4018-23, 2016 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-27277339

RESUMO

Structure effects of distributed feedback (DFB) gratings on lasing action have been investigated for detecting explosive vapors. For the first time, we have established the optimized profiles of the DFB grating, and given the theoretical path to design its structure for amplified spontaneous emission (ASE) of organic polymer films based on Bragg conditions. A poly(p-phenylene ethynylene) (PPE) film can realize detection of dinitrotoluene (DNT) vapors in 2 min with a reduced excitation threshold of 26 mJ cm(-2) by using a simple and common 405 nm laser.

13.
Waste Manag ; 40: 151-6, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25818382

RESUMO

Lead sulfate, lead oxides and lead metal are the main component of lead paste in spent lead acid battery. When lead sulfate was desulfurized and transformed into lead carbonate by sodium carbonate, lead metal and lead oxides remained unchanged. Lead carbonate is easily decomposed to lead oxide and carbon dioxide under high temperature. Namely, vacuum thermal process is the reduction reaction of lead oxides. A compatible environmental process consisted of hydrometallurgical desulfurization and vacuum thermal reduction to recycle lead was investigated in this research. Lead paste was firstly desulfurized with sodium carbonate, by which, the content of sulfur declined from 7.87% to 0.26%. Then, the desulfurized lead paste was reduced by charcoal under vacuum. Under the optimized reaction conditions, i.e., vacuum thermal reduction at temperature 850°C under 20 Pa for 45 min, a 22.11×10(-2) g cm(-2) min(-1) reduction rate, and a 98.13% direct recovery ratio of fine lead (99.77%) had been achieved, respectively.


Assuntos
Fontes de Energia Elétrica , Chumbo/química , Dióxido de Enxofre/química , Enxofre/química , Atmosfera , Dióxido de Carbono/química , Carbonatos/química , Desenho de Equipamento , Metalurgia , Óxidos/química , Pressão , Reciclagem , Temperatura , Termodinâmica , Vácuo , Difração de Raios X
14.
Opt Express ; 22(19): 23592-604, 2014 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-25321825

RESUMO

A method was developed for aligning interference fringes generated in interference lithography to the vertical {111} planes of <110> oriented silicon wafers. The alignment error is 0.036°. This high precision method makes it possible to combine interference lithography with anisotropic wet etch technique for the fabrication of high aspect ratio silicon gratings with extremely smooth sidewalls over a large sample area. With this alignment method, 320 nm and 2 µm period silicon gratings have been successfully fabricated. The highest aspect ratio is up to 100. The sample area is about 50 mm × 60 mm. The roughness (root mean square) of the sidewall is about 0.267 nm.


Assuntos
Nanotecnologia/métodos , Impressão/instrumentação , Silício/química , Anisotropia , Tamanho da Partícula , Propriedades de Superfície
15.
Appl Opt ; 53(6): 1221-7, 2014 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-24663323

RESUMO

In order to improve the efficiency uniformity of large-aperture beam sampling gratings (BSGs), a conventional chemical mechanical polishing (CMP) process of fused silica by CeO2 slurry is proposed to modify their groove profiles. With the proposed CMP process, the efficiency uniformity of several BSGs with an aperture of 430 mm×430 mm has been successfully controlled within an rms of 5%. The proposed CMP process is an effective method to improve the efficiency uniformity of large-aperture BSGs. Using the proposed CMP process, the requirement of the uniformity of the holographic ion beam etching process can be released in the realization of large-aperture BSGs.

16.
Environ Sci Technol ; 47(20): 11734-8, 2013 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-24070094

RESUMO

So far, conventional processes that have been employed to delacquer the paints decorated on used beverage cans (UBCs) are less than satisfactory in economic and environmental effect. Therefore, a new method combining vacuum pyrolysis with dilute sulfuric acid leaching to delacquer the paints was investigated. The results of vacuum pyrolysis showed that the decoating rate increased with the increase of temperature and the paints were almost 100% removed from UBCs under the following conditions: temperature of 650 °C, holding time of 20 min, and residual gas pressure lower than 0.1 kPa. The pyrolysis oil was mainly composed of phenol and 2-methy-phenol analyzed by GC-MS. The delacquered UBCs were subsequently leached with 5% H2SO4 for 60 s and TiO2 was recovered by calcining the residuals in muffle furnace at 450 °C for 15 min. This innovative technology offers an effective method to delacquer paints from UBCs, which obtains excellent stripping effect and avoids the production of toxic substances generated in direct combustion process. Furthermore, the pyrolysis oil can be reused as chemical feedstock in other fields.


Assuntos
Bebidas , Laca/análise , Reciclagem/métodos , Temperatura , Vácuo , Soluções , Espectroscopia de Infravermelho com Transformada de Fourier , Ácidos Sulfúricos/química , Fatores de Tempo , Difração de Raios X
17.
Waste Manag ; 32(8): 1575-82, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22534072

RESUMO

Spent lithium-ion batteries containing lots of strategic resources such as cobalt and lithium are considered as an attractive secondary resource. In this work, an environmentally compatible process based on vacuum pyrolysis, oxalate leaching and precipitation is applied to recover cobalt and lithium from spent lithium-ion batteries. Oxalate is introduced as leaching reagent meanwhile as precipitant which leaches and precipitates cobalt from LiCoO(2) and CoO directly as CoC(2)O(4)·2H(2)O with 1.0 M oxalate solution at 80°C and solid/liquid ratio of 50 g L(-1) for 120 min. The reaction efficiency of more than 98% of LiCoO(2) can be achieved and cobalt and lithium can also be separated efficiently during the hydrometallurgical process. The combined process is simple and adequate for the recovery of valuable metals from spent lithium-ion batteries.


Assuntos
Cobalto/isolamento & purificação , Resíduo Eletrônico , Lítio/isolamento & purificação , Oxalatos/química , Reciclagem/métodos , Precipitação Química , Eletrodos , Peróxido de Hidrogênio/química , Temperatura , Vácuo
18.
J Hazard Mater ; 194: 378-84, 2011 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-21872390

RESUMO

Spent lithium-ion batteries contain lots of strategic resources such as cobalt and lithium together with other hazardous materials, which are considered as an attractive secondary resource and environmental contaminant. In this work, a novel process involving vacuum pyrolysis and hydrometallurgical technique was developed for the combined recovery of cobalt and lithium from spent lithium-ion batteries. The results of vacuum pyrolysis of cathode material showed that the cathode powder composing of LiCoO(2) and CoO peeled completely from aluminum foils under the following experimental conditions: temperature of 600°C, vacuum evaporation time of 30 min, and residual gas pressure of 1.0 kPa. Over 99% of cobalt and lithium could be recovered from peeled cobalt lithium oxides with 2M sulfuric acid leaching solution at 80°C and solid/liquid ratio of 50 g L(-1) for 60 min. This technology offers an efficient way to recycle valuable materials from spent lithium-ion batteries, and it is feasible to scale up and help to reduce the environmental pollution of spent lithium-ion batteries.


Assuntos
Cobalto/isolamento & purificação , Lítio/isolamento & purificação , Vácuo , Pressão , Temperatura
19.
Waste Manag ; 31(12): 2569-76, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21840196

RESUMO

Here, we focused on the recycling of waste printed circuit boards (WPCBs) using vacuum pyrolysis-centrifugation coupling technology (VPCT) aiming to obtain valuable feedstock and resolve environmental pollution. The two types of WPCBs were pyrolysed at 600°C for 30 min under vacuum condition. During the pyrolysis process, the solder of WPCBs was separated and recovered when the temperature range was 400-600°C, and the rotating drum was rotated at 1000 rpm for 10 min. The type-A of WPCBs pyrolysed to form an average of 67.91 wt.% residue, 27.84 wt.% oil, and 4.25 wt.% gas; and pyrolysis of the type-B of WPCBs led to an average mass balance of 72.22 wt.% residue, 21.57 wt.% oil, and 6.21 wt.% gas. The GC-MS and FT-IR analyses showed that the two pyrolysis oils consisted mainly of phenols and substituted phenols. The pyrolysis oil can be used for fuel or chemical feedstock for further processing. The recovered solder can be recycled directly and it can also be a good resource of lead and tin for refining. The pyrolysis residues contained various metals, glass fibers and other inorganic materials, which could be recovered after further treatment. The pyrolysis gases consisted mainly of CO, CO(2), CH(4), and H(2), which could be collected and recycled.


Assuntos
Centrifugação/métodos , Eletrônica/instrumentação , Poluição Ambiental/prevenção & controle , Incineração/métodos , Metais Pesados/isolamento & purificação , Reciclagem/métodos , Resíduos , Dióxido de Carbono/isolamento & purificação , Monóxido de Carbono/isolamento & purificação , Cromatografia Gasosa-Espectrometria de Massas , Hidrogênio/isolamento & purificação , Metano/isolamento & purificação , Espectroscopia de Infravermelho com Transformada de Fourier , Vácuo
20.
Environ Sci Technol ; 45(8): 3361-6, 2011 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-21446728

RESUMO

Anode slime is an important material of recycling precious metals. Up to now, treating the arsenic- and antimony-rich anode slime by conventional processes has the following problems: its economic and environmental effect is less than satisfactory, and the removal effect of arsenic and antimony from anode slime in present processes is not all that could be desired. Therefore, vacuum dynamic flash reduction, a new process for treating arsenic- and antimony-rich anode slime, was investigated in this work. During vacuum dynamic flash reduction, silver from the arsenic- and antimony-rich anode slime was left behind in the distilland as the silver alloy, and trivalent oxides of arsenic and antimony were evaporated in the distillate. The experimental results showed that the evaporation percent of the arsenic- and antimony-rich anode slime was 65.6%. Namely, 98.92% by weight of arsenic and 93.67% by weight of antimony can be removed under the following experimental conditions: temperature of 1083 K, vacuum evaporation time of 60 min, and air flow rate of 400 mL/min corresponding to the residual gas pressure of 250 Pa. Moreover, vacuum treatment eliminates much of the air pollution and material losses associated with other conventional treatment methods.


Assuntos
Antimônio/química , Arsênio/química , Substâncias Perigosas/análise , Gerenciamento de Resíduos/métodos , Antimônio/análise , Arsênio/análise , Fracionamento Químico/instrumentação , Fracionamento Químico/métodos , Eletrodos , Reciclagem , Temperatura , Vácuo , Gerenciamento de Resíduos/instrumentação
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