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1.
Int Immunopharmacol ; 133: 111727, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38636369

RESUMO

Rheumatoid arthritis (RA) is an inflammatory autoimmune disease and management of it still a challenge. Given report evaluates protective effect of phlorizin on RA and also postulates the molecular mechanism of its action. Bovine type II collagen (CIA) and Freund's incomplete adjuvant (1:1 and 1 mg/ml) was administered on 1st and 8th day of protocol to induce RA in rats and treatment with phlorizin 60 and 120 mg/kg was started after 4th week of protocol. Level of inflammatory cytokines and expression of proteins were estimated in phlorizin treated RA rats. Moreover in-vitro study was performed on Fibroblast-like synoviocytes (FLSs) and effect of phlorizin was estimated on proliferation, apoptosis and expression of mTOR pathway protein after stimulating these cell lines with Tumour Necrosis Factor alpha (TNF-α). Data of study suggest that phlorizin reduces inflammation and improves weight in CIA induced RA rats. Level of inflammatory cytokines in the serum and expression of Akt/PI3K/mTOR proteins in the join tissue was reduced in phlorizin treated RA rats. Phlorizin also reported to reverse the histopathological changes in the joint tissue of RA rats. In-vitro study supports that phlorizin reduces proliferation and no apoptotic effect on TNF-α stimulated FLSs. Expression of Akt/PI3K/mTOR proteins also downregulated in phlorizin treated TNF-α stimulated FLSs. In conclusion, phlorizin protects inflammation and reduces injury to the synovial tissues in RA, as it reduces autophagy by regulating Akt/PI3K/mTOR pathway.

2.
J Environ Manage ; 351: 119730, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38086123

RESUMO

In this study, the behavior of heavy metal transformation during the co-thermal treatment of hazardous waste incineration fly ash (HWIFA) and Fe-containing hazardous waste (including hazardous waste incineration bottom slag (HWIBS) and electroplating sludge (ES)) was investigated. The findings demonstrated that such a treatment effectively reduced the static leaching toxicity of Cr and Pb. Moreover, when the treatment temperature exceeded 1000 °C, the co-thermal treated sample exhibited low concentrations of dynamically leached Cr, Pb, and Zn, indicating that these heavy metals were successful detoxified. Thermodynamic analyses and phase transformation results suggested that the formation of spinel and the gradual disappearance of chromium dioxide in the presence of Fe-containing hazardous wastes contributed to the solidification of chromium. Additionally, the efficient detoxification of Pb and Zn was attributed to their volatilization and entry into the liquid phase during the co-thermal treatment process. Therefore, this study sets an excellent example of the co-thermal treatment of hazardous wastes and the control of heavy metal pollution during the treatment process.


Assuntos
Metais Pesados , Eliminação de Resíduos , Cinza de Carvão , Eliminação de Resíduos/métodos , Esgotos/análise , Resíduos Perigosos/análise , Galvanoplastia , Chumbo , Incineração/métodos , Metais Pesados/análise , Resíduos Sólidos/análise , Carbono , Material Particulado/análise
3.
Opt Express ; 31(9): 14570-14582, 2023 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-37157318

RESUMO

A compact fiber-optic temperature sensor with hybrid interferometers enhanced by the harmonic Vernier effect was proposed, which realized 36.9 times sensitization of the sensing Fabry-Perot interferometer (FPI). The hybrid interferometers configuration of the sensor consists of a FPI and a Michelson interferometer. The proposed sensor is fabricated by splicing the hole-assisted suspended-core fiber (HASCF) to the multi-mode fiber fused with the single-mode fiber, and filling polydimethylsiloxane (PDMS) into the air hole of HASCF. The high thermal expansion coefficient of PDMS improves the temperature sensitivity of the FPI. The harmonic Vernier effect eliminates the limitation of the free spectral range on the magnification factor by detecting the intersection response of internal envelopes, and realizes the secondary sensitization of the traditional Vernier effect. Combing the characteristics of HASCF, PDMS, and first-order harmonic Vernier effect, the sensor exhibits a high detection sensitivity of -19.22 nm/°C. The proposed sensor provides not only a design scheme for compact fiber-optic sensors, but also a new strategy to enhance the optical Vernier effect.

4.
J Environ Manage ; 338: 117776, 2023 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-36965423

RESUMO

Based on the CaO-SiO2-Al2O3 system, the feasibility of co-vitrification of hazardous waste incineration fly ash (FA) and hazardous waste sludge (HWS) was verified. In the CaO-SiO2-Al2O3 ternary system diagram, the melting point of the system gradually decreases with an appropriate increase in SiO2 content when the CaO/Al2O3 ratio is determined to be approximately 1. The TG-DSC results revealed that the liquid phase generation temperature in the FA and HWS mixture system was significantly lower than those of FA and HWS individually owing to the different CaO, SiO2, and Al2O3 contents; this is consistent with the results of the theoretical melting characteristics analysis, which show that the melting characteristic temperatures can be reduced by controlling the CaO-SiO2-Al2O3 ratio in the system. The co-vitrification experimental results confirmed that a vitreous content above 92%, a loss ratio on acid dissolution less than 1.74%, and leaching toxicity of heavy metals lower than 0.15 mg/L could be obtained by adjusting the CaO, SiO2, and Al2O3 contents in the FA and HWS system to 20 wt%-32.5 wt%, 35 wt%-61 wt% and 14 wt%-32.5 wt%, respectively, and under a melting temperature of 1350 °C.


Assuntos
Metais Pesados , Eliminação de Resíduos , Cinza de Carvão , Incineração , Dióxido de Silício , Esgotos , Vitrificação , Metais Pesados/análise , Resíduos Sólidos/análise , Eliminação de Resíduos/métodos , Carbono , Resíduos Perigosos , Material Particulado/análise
5.
Sci Rep ; 12(1): 21054, 2022 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-36473904

RESUMO

Three-Dimensional shape measurement has been confronted with the ambiguity on the steep surface. To address the problem, compressed sensing theory is employed to reconstruct phase shifting images in DMD camera. Specially, every CCD pixel in the region of interest is aligned to N × N DMD mirrors to construct DMD camera. The one-dimensional measurement matrices are chosen to collect the measured values on CCD pixel according to the directional judgement of original gradient image. Due to the enhancement of the spatial sampling frequency and the noise robustness, the reconstructed sinusoidal stripe images are utilized to obtain the three-dimensional model of the steep surface accurately. We measure the planes with various slopes to discuss the measurement capability. The comparative experiments show that our proposed method can correct the deformed phase and repair the defect on the steep surface.

6.
Appl Opt ; 61(9): 2432-2437, 2022 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-35333263

RESUMO

Tantalum aluminum carbide (Ta4AlC3) phase ceramic (MAX) material has attracted much attention because of its high conductivity, high strength, corrosion resistance, and good optical properties. However, there are too few reports on lasers with Ta4AlC3-based saturable absorbers (SAs). We prepared and characterized a Ta4AlC3-based SA whose nonlinear absorption performances were achieved at a 2 µm waveband range and which was used in a passively Q-switched (PQS) Tm:YAP laser. In the PQS mode, a maximum average output power of 0.78 W was achieved with the central output wavelength of 1991.86 nm from a PQS Tm:YAP laser, corresponding to a pulse duration of 926 ns at 143.8 kHz.

7.
Nanomaterials (Basel) ; 11(9)2021 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-34578736

RESUMO

Currently, metasurfaces (MSs) integrating with different active materials have been widely explored to actively manipulate the resonance intensity of multi-band electromagnetic induced transparency (EIT) windows. Unfortunately, these hybrid MSs can only realize the global control of multi-EIT windows rather than selective control. Here, a graphene-functionalized complementary terahertz MS, composed of a dipole slot and two graphene-integrated quadrupole slots with different sizes, is proposed to execute selective and active control of dual-band electromagnetic induced reflection (EIR) windows. In this structure, dual-band EIR windows arise from the destructive interference caused by the near field coupling between the bright dipole slot and dark quadrupole slot. By embedding graphene ribbons beneath two quadrupole slots, the resonance intensity of two windows can be selectively and actively modulated by adjusting Fermi energy of the corresponding graphene ribbons via electrostatic doping. The theoretical model and field distributions demonstrate that the active tuning behavior can be ascribed to the change in the damper factor of the corresponding dark mode. In addition, the active control of the group delay is further investigated to develop compact slow light devices. Therefore, the selective and active control scheme introduced here can offer new opportunities and platforms for designing multifunctional terahertz devices.

8.
Sensors (Basel) ; 20(15)2020 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-32751265

RESUMO

In order to improve the performance of fiber sensors and fully tap the potential of optical fiber sensors, various optical materials have been selectively coated on optical fiber sensors under the background of the rapid development of various optical materials. On the basis of retaining the original characteristics of the optical fiber sensors, the coated sensors are endowed with new characteristics, such as high sensitivity, strong structure, and specific recognition. Many materials with a large thermal optical coefficient and thermal expansion coefficients are applied to optical fibers, and the temperature sensitivities are improved several times after coating. At the same time, fiber sensors have more intelligent sensing capabilities when coated with specific recognition materials. The same/different kinds of materials combined with the same/different fiber structures can produce different measurements, which is interesting. This paper summarizes and compares the fiber sensors treated by different coating materials.

9.
Nanoscale ; 12(20): 11182-11191, 2020 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-32406453

RESUMO

Nickel-rich layered cathode materials have aroused widespread interest due to their high discharge capacity, which is a basic requirement for next-generation high energy density lithium batteries. However, with the increase of nickel content, cathode materials face the serious challenge of capacity degradation, which is attributed to the formation of rock salt-type oxides such as NiO on the surface of cathode particles. To overcome this shortcoming, a novel Ni concentration gradient LiNi0.8Co0.15Al0.05O2 (NCG-NCA) cathode material was successfully synthesized using the characteristic reaction of Ni2+ and dimethylglyoxime. The final synthesized nickel concentration gradient material combines the advantages of high discharge capacity and excellent stability, which are attributed to the high nickel content in the core and high cobalt content on the surface of the material particles. The cycling stability of the NCG material is remarkably improved, exhibiting an excellent capacity retention of 75% after 200 cycles at a current density of 10C (1C = 160 mA g-1) under a high cut-off voltage of 4.5 V, much higher than that of a pristine NCA (P-NCA) cathode without NCG (50%). The excellent cycling stability of NCG-NCA is due to formation of a stable surface, which is not prone to serious atomic rearrangement on the surface. More importantly, with the structural analysis of NCA materials by neutron diffraction, we find that the proportion of Li/Ni mixing of NCA is reduced by utilizing the NCG structure; in turn, the rate performance of NCG-NCA cathode materials is improved greatly.

10.
Waste Manag ; 38: 381-7, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25661690

RESUMO

Changes in water states during the composting of kitchen waste were determined. Three experiments, R(55), R(60), and R(65), with different initial moisture contents, 55%, 60%, and 65%, respectively, were performed. Three water states, entrapped water (EW), capillary water (CW), and multiple-molecular-layer water (MMLW), were monitored during the experiments. Changes only occurred with the EW and CW during the composting process. The percentage of EW increased, and the percentage of CW decreased as the composting process progressed. The R(60) experiment performed better than the other experiments according to changes in the temperature and carbon-to-nitrogen ratio (C/N). The percentage of EW correlated well (P<0.05) with the dissolved organic carbon content (DOC), electrical conductivity (EC), pH, and C/N, and was affected by the hemicellulose and cellulose contents.


Assuntos
Resíduos de Alimentos , Reciclagem , Resíduos Sólidos/análise , Água/análise , Eliminação de Resíduos
11.
Environ Sci Pollut Res Int ; 22(3): 2295-302, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25182430

RESUMO

The effects of adding polyacrylamide (PAM), to attempt to delay the loss of capillary water and achieve a better level of organic matter humification, in the composting of kitchen waste were evaluated. Four treatments, with initial moisture content of 60 % were used: 0.1 % PAM added before the start of composting (R1), 0.1 % PAM added when the thermophilic phase of composting became stable (at >50 °C) (R2), 0.1 % PAM added when the moisture content significantly decreased (R3), and no PAM added (R4). The introduction of PAM in R1 and R2 significantly increased the capillary force and delayed the loss of moisture content and capillary water. The introduction of PAM in R2 and R3 improved the composting process, in terms of the degradation of biochemical fractions and the humification degree. These results show that the optimal time for adding PAM was the initial stage of the thermophilic phase.


Assuntos
Resinas Acrílicas/química , Resíduos de Alimentos , Solo , Água/química , Condutividade Elétrica , Temperatura
12.
Bioresour Technol ; 171: 323-9, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25218204

RESUMO

Food waste (FW) was pretreated by a hydrothermal method and then fermented for volatile fatty acid (VFAs) production. The soluble substance in FW increased after hydrothermal pretreatment (⩽200 °C). Higher hydrothermal temperature would lead to mineralization of the organic compounds. The optimal temperature for organic dissolution was 180 °C, at which FW dissolved 42.5% more soluble chemical oxygen demand than the control. VFA production from pretreated FW fermentation was significantly enhanced compared with the control. The optimal hydrothermal temperature was 160 °C with a VFA yield of 0.908 g/g VSremoval. Butyrate and acetate were the prevalent VFAs followed by propionate and valerate. FW fermentation was inhibited after 200 °C pretreatment. The VFAs were extracted from the fermentation broth by liquid-liquid extraction. The VFA recovery was 50-70%. Thus, 0.294-0.411 g VFAs could be obtained per gram of hydrothermally pretreated FW (in dry weight) by this method.


Assuntos
Reatores Biológicos , Ácidos Graxos Voláteis/biossíntese , Alimentos , Temperatura Alta , Resíduos , Água/química , Acetatos/análise , Análise da Demanda Biológica de Oxigênio , Butiratos/análise , Fermentação , Extração Líquido-Líquido
13.
Waste Manag ; 33(5): 1073-8, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23402808

RESUMO

Residues from the imported wastes dismantling process create a great burden on the ambient environment. To develop appropriate strategies for the disposal of such residues, their characteristics were studied through background value analysis and toxicity leaching tests. Our results showed that the heavy metals concentrations in residues were high, particularly those of Cu (7180 mg kg(-1)), Zn (2783 mg kg(-1)), and Pb (1954 mg kg(-1)). Toxicity leaching tests revealed a high metal releasing risk of such residues if they are disposed of in a landfill. However, the residues of imported wastes were also found to have some intrinsic metal recycling value.


Assuntos
Metais Pesados/análise , Eliminação de Resíduos/métodos , China , Cobre/análise , Resíduo Eletrônico/estatística & dados numéricos , Chumbo/análise , Reciclagem , Poluentes do Solo/análise , Resíduos Sólidos , Testes de Toxicidade , Poluentes Químicos da Água/toxicidade , Zinco/análise
14.
Environ Sci Pollut Res Int ; 20(4): 2162-71, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23288673

RESUMO

The high salinity and fat contents of kitchen waste (KW) inhibits the effect of two-phase anaerobic digestion system. This research introduces fruit-vegetable waste (FVW) to alleviate the inhibition effect caused by salinity and fat concentrations, and tries to achieve an optimal addition ratio of FVW, an optimal hydraulic remain time (HRT) of acidogenic-phase reactor and methanogenic-phase reactor. A two-phase anaerobic digestion (AD) system was developed to co-dispose KW and FVW. Four sets of experiments were run with different mass proportions between KW and FVW (25-75, 50-50, 75-25, and 100-0% m/m). Considering the biodegradation rate and the acidification degree, the system with 25% KW had the best performance during the acidogenic phase. When the system was run with 50% KW, it not only had the best stability performance but also had a bigger capacity to treat KW than the system with 25% KW. The system with 50% KW was the best ratio in this two-phase AD system. Co-digestion of KW and FVW by two-phase AD is feasible. The addition of FVW can reduce the inhibition effect caused by salinity and fat concentrations, reduce the HRT, and lead to a higher degree of acidification.


Assuntos
Biodegradação Ambiental , Reatores Biológicos , Alimentos , Eliminação de Resíduos/métodos , Resíduos Sólidos , Anaerobiose , Bactérias Aeróbias , Reatores Biológicos/microbiologia , Frutas , Concentração de Íons de Hidrogênio , Metano/metabolismo , Eliminação de Resíduos/instrumentação , Verduras
15.
Environ Sci Pollut Res Int ; 20(3): 1546-55, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22821340

RESUMO

Ammonia nitrogen pollution control is an urgent issue of landfill. This research aims to select an optimal refuse for ammonia nitrogen removal in landfill from the point of view of adsorption and desorption behavior. MSW (municipal solid waste) samples which deposit ages were in the range of 5 to 15 years (named as R(15), R(11), R(7), and R(5)) were collected from real landfill site. The ammonia nitrogen adsorption behaviors of MSW including equilibrium time, adsorption isotherms, and desorption behaviors including equilibrium time were determined. Furthermore, the effects of pH, OM, Cu(II), Zn(II), and Pb(II) on adsorption and desorption behavior of ammonia nitrogen were conducted by orthogonal experiment. The equilibrium time of ammonia nitrogen adsorption by each tested MSW was very short, i.e., 20 min, whereas desorption process needed 24 h and the ammonia nitrogen released from refuses was much lesser than that adsorbed, i.e., accounted for 3.20 % (R(15)), 14.32 % (R(11)), 20.59 % (R(7)), and 20.50 % (R(5)) of each adsorption quantity, respectively. The maximum adsorption capacity estimated from Langmuir isotherm appeared in R(15)-KCl, i.e., 25,000 mg kg(-1). The best condition for ammonia nitrogen removal from leachate was pH >7.5, OM 23.58 %, Cu(II) <5 mg L(-1), Zn(II) <10 mg L(-1), and Pb(II) <1 mg L(-1). Ammonia nitrogen in landfill leachate could be quickly and largely absorbed by MSW but slowly and infrequently released. The refuse deposited for 15 years could be a suitable material for ammonia nitrogen removal.


Assuntos
Amônia/análise , Poluição Ambiental/prevenção & controle , Resíduos Sólidos/análise , Adsorção , Amônia/química , China , Recuperação e Remediação Ambiental/métodos , Concentração de Íons de Hidrogênio , Fatores de Tempo
16.
Huan Jing Ke Xue ; 31(4): 871-6, 2010 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-20527164

RESUMO

Based on weather data and data obtained by Particle Sizer GRIMM180 set up in Qingdao, aerosol was qualitively classified into sea-fog aerosol, refreshing aerosol and suspended dust aerosol. Analysis of mass concentration and number concentration of three different kinds of aerosols was conducted, and the results are shown as below: 1) total mass concentration of different kinds of aerosol is obviously different; 2) sea-fog aerosol primarily includes particles of which size ranging from 1 microm to 2.5 microm, and refreshing aerosol, includes particles of which size less than 1 microm, and suspended dust aerosol, includes particles of which size ranging from 2.5 microm to 10 microm. 3) precipitation has important role on decreasing larger particle concentration and increasing tiny particle concentration. 4) those tiny particles of which size is less than 1 microm, especially less than 0.6 microm, show an activation phenomenon when they located before the surface weather systems, where air humidity is considerable high. 5) trend of number concentration variability of different particles has different characteristic modes when aerosol property has been changed.


Assuntos
Aerossóis/análise , Poluentes Atmosféricos/análise , Monitoramento Ambiental/métodos , Chuva , Tempo (Meteorologia) , China , Tamanho da Partícula
17.
Opt Express ; 17(8): 6311-9, 2009 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-19365457

RESUMO

For inter-satellite optical communication transmitter with reflective telescope of two-mirrors on axis, a large mount of the transmitted energy will be blocked by central obscuration of the secondary mirror. In this paper, a novel scheme based on diffractive optical element (DOE) is introduced to avoid it. This scheme includes one diffractive beam shaper and another diffractive phase corrector, which can diffract the obscured part of transmitted beam into the domain unobscured by the secondary mirror. The proposed approach is firstly researched with a fixed obscuration ratio of 1/4. Numerical simulation shows that the emission efficiency of new figuration is 99.99%; the beam divergence from the novel inter-satellite optical communication transmitter is unchanged; and the peak intensity of receiver plane is increased about 31% compared with the typical configuration. Then the intensy patterns of receiver plane are analyzed with various obscuration ratio, the corresponding numerical modelling reveals that the intensity patterns with various obscuration ratio are nearly identical, but the amplify of relative peak intensity is getting down with the growth of obscuration ratio. This work can improve the beam quality of inter-satellite optical communication system without affecting any other functionality.


Assuntos
Desenho Assistido por Computador , Lentes , Refratometria/instrumentação , Comunicações Via Satélite/instrumentação , Desenho de Equipamento , Análise de Falha de Equipamento , Controle de Qualidade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
18.
Appl Opt ; 48(4): 786-91, 2009 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-19183609

RESUMO

A truncated ellipse Gaussian model to express localized distortion is developed to a transmission-type optical antenna, based on which the effects of localized deformation on pointing and tracking errors are researched. It is shown that localized distortion has the greatest influence on pointing and tracking errors when distortion deepness h approximately 0.8 lambda, which does not depend on other distortion parameters. To reduce the impact of localized deformation on pointing and tracking errors, the machining precision of the objective lens of the transmission-type antenna should be much better than 0.8 lambda. The requirement of the machining precision for lenses is lower than that for mirrors. The maxima of pointing and tracking errors due to the localized distortion with different radii are given. We hope the results can be used in the design of intersatellite optical communication systems.

19.
Opt Express ; 16(17): 13372-80, 2008 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-18711575

RESUMO

Instead of Zernike polynomials, ellipse Gaussian model is proposed to represent localized wave-front deformation in researching pointing and tracking errors in inter-satellite laser communication links, which can simplify the calculation. It is shown that both pointing and tracking errors depend on the center deepness h, the radiuses a and b, and the distance d of the Gaussian distortion and change regularly as they increase. The maximum peak values of pointing and tracking errors always appear around h=0.2lambda. The influence of localized deformation is up to 0.7microrad for pointing error, and 0.5microrad for tracking error. To reduce the impact of localized deformation on pointing and tracking errors, the machining precision of optical devices, which should be more greater than 0.2?, is proposed. The principle of choosing the optical devices with localized deformation is presented, and the method that adjusts the pointing direction to compensate pointing and tracking errors is given. We hope the results can be used in the design of inter-satellite lasercom systems.


Assuntos
Artefatos , Lasers , Modelos Teóricos , Astronave , Telecomunicações , Simulação por Computador , Luz , Dispositivos Ópticos , Espalhamento de Radiação
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