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1.
Sci Rep ; 14(1): 11452, 2024 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-38769323

RESUMEN

This study addresses the drawbacks of traditional methods used in meter coefficient analysis, which are low accuracy and long processing time. A new method based on non-parametric analysis using the Back Propagation (BP) neural network is proposed to overcome these limitations. The study explores the classification and pattern recognition capabilities of the BP neural network by analyzing its non-parametric model and optimization methods. For model construction, the study uses the United Kingdom Domestic Appliance-Level Electricity dataset's meter readings and related data for training and testing the proposed model. The non-parametric analysis model is used for data pre-processing, feature extraction, and normalization to obtain the training and testing datasets. Experimental tests compare the proposed non-parametric analysis model based on the BP neural network with the traditional Least Squares Method (LSM). The results demonstrate that the proposed model significantly improves the accuracy indicators such as mean absolute error (MAE) and mean relative error (MRE) when compared with the LSM method. The proposed model achieves an MAE of 0.025 and an MRE of 1.32% in the testing dataset, while the LSM method has an MAE of 0.043 and an MRE of 2.56% in the same dataset. Therefore, the proposed non-parametric analysis model based on the BP neural network can achieve higher accuracy in meter coefficient analysis when compared with the traditional LSM method. This study provides a novel non-parametric analysis method with practical reference value for the electricity industry in energy metering and load forecasting.

2.
Int Immunopharmacol ; 133: 111727, 2024 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-38636369

RESUMEN

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.


Asunto(s)
Artritis Experimental , Artritis Reumatoide , Hiperplasia , Florizina , Transducción de Señal , Sinoviocitos , Serina-Treonina Quinasas TOR , Animales , Serina-Treonina Quinasas TOR/metabolismo , Artritis Reumatoide/tratamiento farmacológico , Artritis Reumatoide/patología , Transducción de Señal/efectos de los fármacos , Artritis Experimental/tratamiento farmacológico , Artritis Experimental/patología , Sinoviocitos/efectos de los fármacos , Sinoviocitos/patología , Hiperplasia/tratamiento farmacológico , Ratas , Florizina/farmacología , Florizina/uso terapéutico , Citocinas/metabolismo , Masculino , Membrana Sinovial/efectos de los fármacos , Membrana Sinovial/patología , Proliferación Celular/efectos de los fármacos , Apoptosis/efectos de los fármacos , Antiinflamatorios/farmacología , Antiinflamatorios/uso terapéutico , Ratas Wistar , Células Cultivadas , Proteínas Proto-Oncogénicas c-akt/metabolismo , Humanos , Fosfatidilinositol 3-Quinasas/metabolismo , Factor de Necrosis Tumoral alfa/metabolismo
3.
In Vivo ; 38(3): 1182-1191, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38688626

RESUMEN

BACKGROUND/AIM: Rheumatoid arthritis (RA) is an inflammatory autoimmune disease, and management of it is still a challenge. The present investigation assessed the potential preventive effect of phlorizin on rats with RA. MATERIALS AND METHODS: A total of 40 healthy Wistar rats were used for this study. Bovine type II collagen and Freund's incomplete adjuvant (1:1 and 1 mg/ml) were administered on days 1 and 8 of the protocol to induce RA in rats; treatment with phlorizin at 60 or 120 mg/kg was started after the 4th week of the protocol, and its effect on inflammation, level of inflammatory cytokines, and expression of proteins were estimated in RA rats. Moreover, an in vitro study was performed on fibroblast-like synoviocytes (FLSs), and the effects of phlorizin on proliferation, apoptosis, and expression of the mechanistic target of rapamycin kinase pathway protein after stimulating these cells with tumor necrosis factor α (TNF-α) were estimated. RESULTS: The data obtained from the study indicate that phlorizin has the potential to mitigate inflammation and enhance weight management in rats with RA induced by bovine type II collagen (CII). The level of inflammatory cytokines in the serum and the expression of protein kinase B (AKT), phosphatidylinositol-4,5-bisphosphate 3-kinase (PI3K), and mechanistic target of rapamycin kinase (mTOR) proteins in the joint tissue were reduced in phlorizin-treated rats with RA. In this investigation, phlorizin was shown to reverse the histological abnormalities in the joint tissue of rats with RA. The in-vitro study showed that phlorizin reduced proliferation and had no apoptotic effect on TNF-α-stimulated FLSs. Expression of AKT, PI3K, and mTOR proteins was also down-regulated in phlorizin-treated TNF-α-stimulated FLSs. CONCLUSION: Phlorizin protects against inflammation and reduces injury to synovial tissues in RA by modulating the AKT/PI3K/mTOR pathway.


Asunto(s)
Artritis Reumatoide , Hiperplasia , Inflamación , Florizina , Transducción de Señal , Sinoviocitos , Serina-Treonina Quinasas TOR , Animales , Artritis Reumatoide/tratamiento farmacológico , Artritis Reumatoide/metabolismo , Artritis Reumatoide/patología , Serina-Treonina Quinasas TOR/metabolismo , Ratas , Transducción de Señal/efectos de los fármacos , Florizina/farmacología , Inflamación/patología , Inflamación/tratamiento farmacológico , Inflamación/metabolismo , Sinoviocitos/efectos de los fármacos , Sinoviocitos/metabolismo , Sinoviocitos/patología , Membrana Sinovial/efectos de los fármacos , Membrana Sinovial/metabolismo , Membrana Sinovial/patología , Modelos Animales de Enfermedad , Citocinas/metabolismo , Proliferación Celular/efectos de los fármacos , Apoptosis/efectos de los fármacos , Masculino , Artritis Experimental/tratamiento farmacológico , Artritis Experimental/patología , Artritis Experimental/metabolismo , Ratas Wistar , Proteínas Proto-Oncogénicas c-akt/metabolismo
4.
J Environ Manage ; 351: 119730, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38086123

RESUMEN

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.


Asunto(s)
Metales Pesados , Eliminación de Residuos , Ceniza del Carbón , Eliminación de Residuos/métodos , Aguas del Alcantarillado/análisis , Residuos Peligrosos/análisis , Galvanoplastia , Plomo , Incineración/métodos , Metales Pesados/análisis , Residuos Sólidos/análisis , Carbono , Material Particulado/análisis
5.
Opt Express ; 31(9): 14570-14582, 2023 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-37157318

RESUMEN

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.

6.
J Environ Manage ; 338: 117776, 2023 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-36965423

RESUMEN

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.


Asunto(s)
Metales Pesados , Eliminación de Residuos , Ceniza del Carbón , Incineración , Dióxido de Silicio , Aguas del Alcantarillado , Vitrificación , Metales Pesados/análisis , Residuos Sólidos/análisis , Eliminación de Residuos/métodos , Carbono , Residuos Peligrosos , Material Particulado/análisis
7.
Sci Rep ; 12(1): 21054, 2022 Dec 06.
Artículo en Inglés | MEDLINE | ID: mdl-36473904

RESUMEN

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.

8.
Appl Opt ; 61(9): 2432-2437, 2022 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-35333263

RESUMEN

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.

9.
Nanomaterials (Basel) ; 11(9)2021 Sep 17.
Artículo en Inglés | MEDLINE | ID: mdl-34578736

RESUMEN

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.

10.
Sensors (Basel) ; 20(15)2020 Jul 29.
Artículo en Inglés | MEDLINE | ID: mdl-32751265

RESUMEN

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.

11.
Nanoscale ; 12(20): 11182-11191, 2020 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-32406453

RESUMEN

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.

12.
Waste Manag ; 38: 381-7, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25661690

RESUMEN

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.


Asunto(s)
Residuos de Alimentos , Reciclaje , Residuos Sólidos/análisis , Agua/análisis , Eliminación de Residuos
13.
Environ Sci Pollut Res Int ; 22(3): 2295-302, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25182430

RESUMEN

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.


Asunto(s)
Resinas Acrílicas/química , Residuos de Alimentos , Suelo , Agua/química , Conductividad Eléctrica , Temperatura
14.
Bioresour Technol ; 171: 323-9, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25218204

RESUMEN

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.


Asunto(s)
Reactores Biológicos , Ácidos Grasos Volátiles/biosíntesis , Alimentos , Calor , Residuos , Agua/química , Acetatos/análisis , Análisis de la Demanda Biológica de Oxígeno , Butiratos/análisis , Fermentación , Extracción Líquido-Líquido
15.
Waste Manag ; 33(5): 1073-8, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23402808

RESUMEN

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.


Asunto(s)
Metales Pesados/análisis , Eliminación de Residuos/métodos , China , Cobre/análisis , Residuos Electrónicos/estadística & datos numéricos , Plomo/análisis , Reciclaje , Contaminantes del Suelo/análisis , Residuos Sólidos , Pruebas de Toxicidad , Contaminantes Químicos del Agua/toxicidad , Zinc/análisis
16.
Environ Sci Pollut Res Int ; 20(4): 2162-71, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23288673

RESUMEN

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.


Asunto(s)
Biodegradación Ambiental , Reactores Biológicos , Alimentos , Eliminación de Residuos/métodos , Residuos Sólidos , Anaerobiosis , Bacterias Aerobias , Reactores Biológicos/microbiología , Frutas , Concentración de Iones de Hidrógeno , Metano/metabolismo , Eliminación de Residuos/instrumentación , Verduras
17.
Environ Sci Pollut Res Int ; 20(3): 1546-55, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22821340

RESUMEN

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.


Asunto(s)
Amoníaco/análisis , Contaminación Ambiental/prevención & control , Residuos Sólidos/análisis , Adsorción , Amoníaco/química , China , Restauración y Remediación Ambiental/métodos , Concentración de Iones de Hidrógeno , Factores de Tiempo
18.
Huan Jing Ke Xue ; 31(4): 871-6, 2010 Apr.
Artículo en Chino | MEDLINE | ID: mdl-20527164

RESUMEN

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.


Asunto(s)
Aerosoles/análisis , Contaminantes Atmosféricos/análisis , Monitoreo del Ambiente/métodos , Lluvia , Tiempo (Meteorología) , China , Tamaño de la Partícula
19.
Opt Express ; 17(8): 6311-9, 2009 Apr 13.
Artículo en Inglés | MEDLINE | ID: mdl-19365457

RESUMEN

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.


Asunto(s)
Diseño Asistido por Computadora , Lentes , Refractometría/instrumentación , Comunicaciones por Satélite/instrumentación , Diseño de Equipo , Análisis de Falla de Equipo , Control de Calidad , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
20.
Appl Opt ; 48(4): 786-91, 2009 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-19183609

RESUMEN

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.

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