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High performance hydrophobic Pt/SiO2 as an adsorbent buffer catalyst for toluene removal.

Automatic epileptic seizure detection technologies for clinical diagnosis mainly rely on electroencephalogram (EEG) recordings, which are immensely useful tools for epileptic location and identification. Currently, traditional seizure detection methods based only on single-view features have great limitations for the typical dynamic and nonlinear EEG signals. An objective of this paper is to investigate the effect of multiview feature selection and multilevel spectral analysis methods on the identification of the EEG signals for seizure detection. Here, multiview features are extracted from time domain, frequency domain, and information theory to collect adequate information of EEG signals. And a feature selection algorithm based on particle swarm optimization (PSO) is proposed for automatic seizure detection. Moreover, due to the different frequency components of the EEG signals, they are divided into four kinds of brain waves for multilevel spectral analysis. The effect of these four rhythm waves on seizure detection is compared. Three well-known classifiers are employed to classify EEG signals concerning seizure or nonseizure events. The result shows that the average accuracy, specificity, and sensitivity of classification with the CHB-MIT database are 98.14%, 98.64%, and 96.79%, respectively. The application of the PSO-based feature selection method for automatic seizure detection improves accuracy by 5.99% with the SVM classifier. Compared with the state-of-the-art methods, the proposed method has superior competence with high performance for automatic seizure detection. It is further shown that the feature selection method is an indispensable step in seizure detection. With PSO-based feature selection and multilevel spectral analysis, the θ wave in the frequency range of 4-7 Hz shows better performance in the identification of EEG signals and is more suitable for the proposed method. The PSO-based feature selection algorithm for automatic seizure detection can be a useful assistant tool for clinical diagnosis.

The distinction of dechlorination over activation sites with the aid of Ru/TiO2 catalysts derived from MOFs.

As a significant source of indoor and outdoor pollutants, cooking fumes have a great impact on air quality and human health. However, the limited identification and quantification techniques hinder the comprehensive understanding of the complex cooking fumes with wide volatility and polarity. Herein we applied thermal desorption comprehensive two-dimensional gas chromatography-mass spectrometer (TD-GCxGC-MS) for synchronous analysis of gaseous and particulate organics emitted from cooking fumes. With a systematic 4-step qualitative procedure and precise quantitative and semi-quantitative method, 170 and 352 compounds from C2 (acetic acids) – C30 (squalene) occupying 95 % and 90 % of the total ion current for gaseous and particulate samples were identified and quantified. For most compounds, the correlation coefficient (R2) is >0.9, and the relative standard deviation (RSD, n=5) of three concentration levels (low, medium, high) is within 10 %. For the semi-quantification, the total uncertainty is ~27 %. Compared with gas chromatography-mass spectrometer (GC-MS) and proton transfer time-of-flight mass spectrometer (PTR-ToF-MS), TD-GCxGC-MS detects more compounds, especially the diagnostic tracers related to cooking oil and matierial, and additives added during cooking and secondary products transformed from carbonyls and acids. Hence, TD-GCxGC-MS provides plenty of perspectives to analyze the primary emission and secondary formation from cooking at a molecular level.

To elucidate the molecular chemical compositions, volatility-polarity distributions, as well as influencing factors of Chinese cooking emissions, a comprehensive cooking emission experiment was conducted. Semi-volatile and intermediate volatility organic compounds (S/IVOCs) from cooking fumes were analyzed by a thermal desorption comprehensive two-dimensional gas chromatography coupled with quadrupole mass spectrometer (TD-GC×GC-qMS). Emissions from four typical Chinese dishes, i.e., fried chicken, Kung Pao chicken, pan-fried tofu, and stir-fried cabbage were investigated to illustrate the impact of cooking style and material. Fumes of chicken fried with corn, peanut, soybean, and sunflower oils were investigated to demonstrate the influence of cooking oil. A total of 201 chemicals were quantified. Dishes cooked by stir-frying or deep-frying cooking styles emit much more pollutants than relatively mild cooking methods. Aromatics and oxygenated compounds were extensively detected among meat-related cooking fumes, while a vegetable-related profile was observed in the emissions of stir-fried cabbage. The volatility-polarity distributions of the four dish emissions were quite similar, yet the distributions diverged when different types of oils were utilized. Ozone formation potential (OFP) was dominated by chemicals in the VOC range. 10.2 % - 32.0 % of the SOA estimation could be explained by S/IVOCs. Pixel-based partial least squares-discriminant analysis (PLS-DA) and multiway principal component analysis (MPCA) were utilized for sample classification and key components identification. The results indicated that the oil factor explained more variance of chemical compositions than the cooking style factor. MPCA results emphasize the importance of the unsaturated fatty acid-alkadienal-volatile products mechanism (oil autooxidation) accelerated by the cooking and heating procedure.

Human body area communication has been widely used in the fifth-generation (5G) wireless communication systems. Human bodies bring complexity for channel modeling, and directly affect the performance of the wireless communication systems. In this letter, channel measurements, simulations, and modeling are carried out in a curved tunnel scenario with several human bodies. A human body is modeled by two typical methods to analyze the influence of the channel modeling on the accuracy based on measurements and the innovative ray-tracing method. The comparison of path loss models is provided and a novel generalized path loss model in terms of the curved tunnel scenario is proposed. Multipath dispersion properties are characterized and corresponding statistical distributions are also investigated. Furthermore, the multipath component parameters including angular characteristics of angle of arrival and power of multipath components are analyzed. Multipath clustering is identified using the multipath component distance.

A series of nanocrystalline copper–manganese oxides (denoted as Cu3−xMnx, x = 0, 1, 1.5, 2, 2.5, 3, where x means the molar ratio of Cu and Mn) were successfully prepared by a facile citric acid sol–gel method. The combination of Cu2+ and Mn3+ is intensified and enhanced interface effects generated, which is beneficial for the catalytic oxidation of benzene. A series of analyses, such as X-Ray Diffraction (XRD), N2 adsorption–desorption, X-ray photoelectron spectroscopy (XPS), and hydrogen temperature programmed reduction (H2-TPR), were employed to further investigate the structural properties of the catalysts. An optimal Mn/Cu ratio of 2 forms CuMn2O4 spinels. CuMn2 with CuMn2O4 spinel structure presents a larger specific surface area, smaller pore diameter as well as more lattice oxygen species, exhibiting remarkable activity and stability for the catalytic oxidation of benzene. On account of these factors, CuMn2 possesses better low temperature reducibility and shows the best catalytic performance with 90% benzene conversion at 186 °C. The enhanced catalytic activity of CuMn2 is attributed to the stabilization of CuMn2O4 active phases and the intensive synergistic effect between Cu–Mn oxides. To prove the effect of CuMn2O4 spinel structure on catalytic performance, a CuO/Mn2O3 mixed catalyst (molar ratio 1 : 1) was prepared and applied to benzene oxidation (T90% = 198 °C), which indicates that the spinel structure has an encouraging effect on benzene catalysis. The catalytic properties of single copper oxide and manganese trioxide were also tested, the results show that CuMn2O4 has a crucial role in facilitating electronic transmission and mobility of the lattice oxygen.

In the present work, we conducted experiments of secondary organic aerosol (SOA) formation from urban cooking and vehicular sources to characterize the mass spectral features of primary organic aerosol (POA) and SOA using an high-resolution time-of-flight aerosol mass spectrometer (HR-ToF-AMS). Our results showed that the cooking styles have a greater impact on aged COA (cooking organic aerosol) mass spectra than oxidation conditions. However, the oxidation conditions affect the aged HOA (hydrocarbon-like OA) spectra more significantly than vehicle operating conditions. In our study, we use mass spectra similarity analysis and positive matrix factorization (PMF) analysis to establish the POA and SOA mass spectra of these two sources. These mass spectra are used as source constraints in a multilinear engine (ME-2) model to apportion the OA (organic aerosol) sources in the atmosphere. Compared with the traditional ambient PMF results, the improved ME-2 model can better quantify the contribution of POA and SOA from cooking and vehicular sources. Our work, for the first time, establishes the vehicle and cooking SOA source profiles, and can be further used in the OA source apportionment in the ambient atmosphere.

Monolithic catalysts with high catalytic activity bring about increasing interest in practical environmental purification field for volatile organic compounds (VOCs) degradation with low pressure drops. Monolithic CoMnAlO catalysts with varied Co/Mn molar ratio derived from in situ supported layered double hydroxides (LDH) film are prepared through ammonia hydrothermal growing on Al substrate following calcinations. The textural properties for CoMnAlO catalysts with low temperature reducibility, surface element species are controlled by tuning the initial Co/Mn molar ratio verified through H2-TPR and XPS spectra. CoMn2AlO film sample shows best activity with the temperature for 90% benzene decomposition (T90) around 238 °C with space velocity 300,000 ml gcat−1 h−1. The reaction rate of CoMn2AlO film is about 1.32 mmol gcat−1 h−1 at 260 °C with T99, which is nearly two times to that of Co3AlO film catalyst with 0.73 mmol gcat−1 h−1, because of the higher Mn4+/Mn3+ and Co3+/Co2+ atomic ratios and reducibility inducing by the synergistic effect of Co and Mn. The value is five times higher than CoMn2AlO powder catalyst with 0.26 mmol gcat−1 h−1, which is due to the great exposure active sites.

High reactivity and sintering resistance are key factors to design outstanding CH4 oxidation noble metal-based supported catalysts. Herein, we prepared and screened 0.5 wt% Pd/Al2O3 (among 0.3–3 wt% Pd loading) samples prepared by wet impregnation with very high CH4 catalytic activity. The hydrophobic modification of γ-Al2O3 support by triethoxyoctylsilane (TEOOS) exhibits further enhanced activity for CH4 oxidation, ca. T90 decrease from 375 °C to 350 °C with enhanced concentration of surface Pd0 sites. Besides, after Al2O3 protection layer deposition over the 0.5 wt% Pd/Al2O3 by atomic layer deposition (ALD), distinct higher temperature stability due to reduced agglomeration was demonstrated.

Herein, we reported the synthesis of well-defined Co3O4 nanoarrays (NAs) supported on a monolithic three-dimensional macroporous nickel (Ni) foam substrate for use in high-efficiency CO oxidation. The monolithic Co3O4 NAs catalysts were obtained through a generic hydrothermal synthesis route with subsequent calcination. By controlling the reaction time, solvent polarity and deposition agent, these Co3O4 NAs catalysts exhibited various novel morphologies (single or hybrid arrays), whose physicochemical properties were further characterized by using several analytical techniques. Based on the catalytic and characterization analyses, it was found that the Co3O4 NAs-6 catalyst with nanobrush and nanomace arrays displayed enhanced catalytic activity for CO oxidation, achieving an efficient 100% CO oxidation conversion at a gas hourly space velocity (GHSV) 10,000 hr− 1 and 150°C with long-term stability. Compared with the other Co3O4 NAs catalysts, it had the highest abundance of surface-adsorbed oxygen species, excellent low-temperature reducibility and was rich in surface-active sites (Co3 +/Co2 + = 1.26).

In the present work, we conducted experiments of secondary organic aerosol (SOA) formation from urban lifestyle sources (cooking and vehicle) to characterize the mass spectral features of primary organic aerosol (POA) and SOA using an high-resolution time-of-flight aerosol mass spectrometer (HR-ToF-AMS). Our results showed that the cooking styles have greater impact on aged COA mass spectra than oxidation condition. However, the oxidation conditions affect the aged HOA spectra more significantly than vehicle operation conditions. In our study, we use mass spectra similarity analysis and positive matrix factorization (PMF) analysis to establish the POA and SOA mass spectra of these two typical lifestyle sources. These mass spectra are used as source constraints in a multilinear engine (ME-2) model to apportion the OA sources in the atmosphere. Comparing with the traditional ambient PMF results, the improved ME-2 model can better quantify the contribution of POA and SOA from life-style sources. Our work, for the first time, establishes the vehicle and cooking SOA source profiles, and can be further used in the OA source apportionment in the ambient atmosphere.

Both vehicle exhaust and cooking emission are closely related to the daily life of city dwellers, which are considered as major sources of urban secondary organic aerosol (SOA). Here, we defined the SOA derived from vehicle exhaust and cooking emission as Urban Lifestyle SOA, and simulated their formation using a Gothenburg potential aerosol mass reactor (Go: PAM). After samples had been aged under 0.3–5.5 days of equivalent photochemical age, these two urban lifestyle SOA showed markedly distinct features in SOA mass growth potentials, oxidation pathways and mass spectra. The SOA / POA mass ratios of vehicle groups (107) were 44 times larger than those of cooking groups (2.38) at about 2 days of equivalent photochemical age. It reveals that organics from vehicle may undergo the alcohol/peroxide and carboxylic acid oxidation pathway to produce abundant less/more oxidized oxygenated OA (LO-OOA and MO-OOA), and only a few primary hydrocarbon-like organic aerosol (HOA) remains unaged. In contrast, organics from cooking may undergo the alcohol/peroxide oxidation pathway to produce moderate LO-OOA, and comparable primary cooking organic aerosol (COA) remains unaged. Our findings provide an insight into atmospheric contributions and chemical evolutions for urban lifestyle SOA, which would greatly influence the air quality and health risk assessments in urban areas.

In this paper, the millimeter-wave propagation characteristics at 60 GHz for fifth generation (5G) wireless communication systems in corridor environment are studied based on the method of shooting and bounding ray tracing/image (SBR/IM). Firstly, the correctness of the simulation is verified by comparing with the measured data. In addition, the simulation of line-of-sight (LOS) and non-line-of-sight (NLOS) environment is carried out. The propagation characteristics, including path loss and power angle profile are discussed.

Wireless communication at millimeter-wave bands has been a research hot spot in the latest years. In this paper, a typical urban microcell environment is simulated at 73 GHz in line-of-sight scenarios (LoS) and non-line-of-sight (NLoS) scenarios by the SBR method. First, the validity of the SBR method is verified by comparing the measurement and simulation results of path loss. Next, the propagation characteristics in LoS and NLoS scenarios are studied, such as power angle profiles and power delay angle profiles. Some characteristics of the millimeter-wave channel are revealed from these analyses.

A series of V2O5/TiO2 catalysts with high vanadium loading (6.0 ∼ 43.9 wt%) were prepared by wet impregnation over metal–organic framework (MOF) MIL-125(Ti) support following calcination, and were tested for catalytic combustion of 100 ppm chlorobenzene. Taking advantage of MIL-125(Ti) with high surface area, copious catalytically active VOx species generated in the case of high vanadium loading, among which 0.4VTi, 0.6VTi and 0.8VTi showed 100% chlorobenzene conversion at 250 °C. The effect of vanadium loading on the catalysts have been characterized by means of XRD, SEM, TEM, ICP-OES, N2 adsorption–desorption at 77 K, Raman, NH3-TPD and H2-TPR. The reaction mechanism of chlorobenzene over the as-prepared catalysts was also proposed by in situ DRIFTS.

As an emerging p-conjugated materials, graphitic carbon nitride (g-C3N4) has captured worldwide attention due to impending energy crisis and increasingly serious environmental contamination. In this work, the two-dimensional (2D) MgFe mixed metal oxide (MMO) derived from the layered double hydroxides precursor was employed to construct 2D/2D nanosheet heterojunction with g-C3N4. The formed CN/MgFe-30 nanosheet heterojunctions exhibited the optimal photocatalytic hydrogen production about 6.64 times (1.26 mmol/g−1·h−1) than that of pure g-C3N4 under the visible light irradiation, which were attributed to unique inter-plane 2D/2D structure and excellent synergistic effect between g-C3N4 and MgFe MMO. The experiment characterization proved that MgFe MMO nanosheet not only suppressed the overgrowth of g-C3N4, resulting in the formation of nanoscale g-C3N4, but also facilitated the photoinduced carrier separation and transfer based on 2D/2D CN/MgFe-X nanosheet heterojunctions. This proposed synthesis strategy pave a way to realize the large-scale production of nano-g-C3N4 based 2D/2D nanosheet heterojunctions photocatalysts for hydrogen production.

SVM (Support Vector Machine) is a modern Data-Mining method. It is good at processing large amounts of data and has high accuracy. In this paper, an indoor 60 GHz millimeter wave channel model based on PSO (Particle Swarm Optimization) optimized SVM is established. The prediction results of GA (Genetic Algorithm) and Grid-Search optimized SVM are compared. The simulation results show the PSO optimized SVM model has high prediction accuracy

In this paper, the method of shooting and bounding ray tracing/image (SBR/IM) is used in the simulation of indoor office environment, with which the study on millimeter-wave propagation characteristics can be processed well. Through simulation parameters such as path loss, received power and root mean square (RMS) delay spread is obtained and analyzed. All the results of this paper could be used as a reference when setting the position of transmitter and selecting parameters in indoor office environments.

The synthesis of effective and recyclable Fenton-like catalyst is still a key factor for advanced oxidation processes. Herein, magnetic porous Fe3O4/carbon octahedra were constructed by a two-step controlled calcination of iron-based metal organic framework. The porous octahedra were assembled by interpenetrated Fe3O4 nanoparticles coated with graphitic carbon layer, offering abundant mesoporous channels for the solid-liquid contact. Moreover, the oxygen-containing functional groups on the surface of graphitic carbon endow the catalysts with hydrophilic nature and well-dispersion into water. The porous Fe3O4/carbon octahedra show efficiently heterogeneous Fenton-like reactions for decomposing the organic dye methylene blue (MB) with the help of H2O2, and nearly 100% removal efficiency within 60 min. Furthermore, the magnetic catalyst retains the activity after ten cycles and can be easily separated by external magnetic field, indicating the long-term catalytic durability and recyclability. The good Fenton-like catalytic performance of the as-synthesized Fe3O4/carbon octahedra is ascribed to the unique mesoporous structure derived from MOF-framework, as well as the sacrificial role and stabilizing effect of graphitic carbon layer. This work provides a facile strategy for the controllable synthesis of integrated porous octahedral structure with graphitic carbon layer, and thereby the catalyst holds significant potential for wastewater treatment.

Direct Z-scheme heterojunction can effectively enhance the photocatalytic activity due to its low carrier recombination rate and high redox ability. In this study, a 2D/2D ZnO/ZnxCd1−xS single crystal nanosheet heterojunction is synthesized in situ by topotactic sulfurization/oxidization pyrolysis of Zn/Cd/Al layer double hydroxides (LDHs). Its unique structure provides not only numerous intimate interfaces but also a direct Z-scheme junction. The in situ topotactic fabrication of ZnO by the oxidation process causes some Zn ions to dissolve out from the Zn0.67Cd0.33S solid solution nanosheets with increase in annealing temperature and time. The longer the time for oxidation, the more ZnO is obtained. The formation of ZnO yields 2D/2D ZnO/ZnxCd1−xS single crystal nanosheet heterojunction, which increases the visible light absorption and boosts the separation of photogenerated carriers. The ZnO/ZnxCd1−xS-4 single crystal nanosheet heterojunction presents the highest photocatalytic activity under visible light irradiation (38.93 mmol h−1 g−1), which is nearly 16.93 times higher than that of Zn0.67Cd0.33S-300, and an external quantum efficiency of 40.97% at λ = 420 nm. The proposed synthetic route for the construction of 2D/2D ZnO/ZnxCd1−xS single crystal nanosheet provides a direct Z-scheme structure with highly efficient photocatalytic hydrogen evolution activity.

Advanced integrated nanoarray (NA) catalysts have been designed by growing metal-doped Co3O4 arrays on nickel foam with robust adhesion. Ternary MCo2O4 NA catalysts were prepared by doping urchin-like Co3O4 with different transition metals (Cu2+, Mn2+, Fe2+, Ni2+, Zn2+, Fe3+ and Al3+). These catalysts exhibited novel morphologies and can be directly applied as monolithic materials for CO oxidation. Among the MCo2O4 NA catalysts, CuCo2O4 nanoneedles manifested the highest catalytic activity in dry air, achieving an efficient 100% CO oxidation conversion of 20 000 h−1 at 146 °C, due to its reducibility at lower temperature, lattice distortion of the spinel structure, and abundant surface-adsorbed oxygen (Oads). The doped catalytic systems were further optimized by controlling the volume ratio of reactive components in the mixed solvent, the Cu or Mn contents to determine excellent catalysts for direct application to CO oxidation at 1.0 vol% moisture. Penthorum chinense-like MnCo2O4 NAs showed optimal catalytic performance at 1 vol% moisture (T100 = 175 °C), with activity higher than that of the CuCo2O4 NA catalyst, indicating that the synergistic effect between MnOx and Co3O4 improved the moisture resistance and stability. It was concluded that the moisture resistance provided by introducing active sites on Co-based catalysts decreased as follows: Mn sites > Co sites > Cu sites > Ni sites. MCo2O4 NAs, with predominantly exposed {110} surfaces, showed higher catalytic activity than catalysts with exposed {111} surfaces. This study suggests that the as-prepared MnCo2O4 NAs anchored on 3D Ni foam with remarkable moisture resistance have potential applications in CO oxidation.

A generic hydrothermal synthesis route has been successfully designed and utilized to in situ grow highly ordered Co3O4 nanoarray (NA) precursors on Ni substrates, forming a series of Co3O4 nanoarray-based monolithic catalysts with subsequent calcination. The morphology evolution of Co3O4 nanostructures which depends upon the reaction time, with and without CTAB or NH4F is investigated in detail, which is used to further demonstrate the growth mechanism of Co3O4 nanoarrays with different morphologies. CO is chosen as a probe molecule to evaluate the catalytic performance over the synthesized Co-based oxide catalysts, and the effect of morphological transformation on the catalytic activity is further confirmed via using TEM, H2-TPR, XPS, Raman spectroscopy and in situ Raman spectroscopy. As a proof of concept application, core-shell Co3O4 NAs-8 presenting hierarchical nanosheets@nanoneedle arrays with a low density of nanoneedles exhibits the highest catalytic activity and long-term stability due to its low-temperature reducibility, the lattice distortion of the spinel structure and the abundance of surface-adsorbed oxygen (Oads). It is confirmed that CO oxidation on the surface of Co3O4 can proceed through the Langmuir-Hinshelwood mechanism via using in situ Raman spectroscopy. It is expected that the in situ synthesis of well-defined Co3O4 monolithic catalysts can be extended to the development of environmentally-friendly and highly active integral materials for practical industrial catalysis.

Ceria zirconia solid solution with high oxygen storage capacity (OSC) and thermal stability under 1000 ​°C is quite important for support materials in three-way catalysts (TWCs). In this work, Ce1-xZrxO2 with different Zr dopants (x ​= ​0, 0.125, 0.250 and 0.375) have been prepared by flame spray pyrolysis (FSP) with carboxylic acid or ethanol and carboxylic acid (v:v 1:4) solvents. The influences of Zr content and the addition of ethanol into carboxylic acid on the OSC performance and thermal stability have been systematically characterized by X-ray diffraction (XRD), N2 adsorption-desorption, Raman analysis, field emission scanning electron microscope (FESEM), high resolution transmission electron microscope (HRTEM), X-ray photoelectron spectroscopy (XPS), hydrogen-temperature programmed reduction (H2-TPR), and pulse thermal analysis using H2 as reducing agent. The presence of cubic-tetragonal interfaces in the Ce0.750Zr0.250O2 sample can enhance the formation of oxygen vacancies and the mobility of lattice oxygen in ceria-zirconia solutions, which results in the largest OSC (349 ​μmol ​g−1) among the fresh samples. The cubic-tetragonal interfaces in the Ce0.750Zr0.250O2 sample can also promote the thermal stability under 1000 ​°C to preserve better OSC (202 ​μmol ​g−1) than other aged samples. Furthermore, after adding with ethanol into carboxylic acid solvent, the OSC of the sample further increases to 371 ​μmol ​g−1 for the increment of oxygen vacancy concentration. It is worthy to note that the introduction of ethanol can suppress Zr migration from the lattice to the surface of CeO2 at high temperature, further enhancing OSC (240 ​μmol ​g−1) and thermal stability.

A series of silica supported Mn–Ce composite oxides with different Mn/Ce molar ratios were obtained by a simple and environment-friendly oxalate route. The physical and chemical properties were characterized by TG, BET, SEM, TEM, XPS and TPR analysis. All catalysts showed excellent activity towards deep oxidation of benzene. The effects of Mn/Ce ratio, calcination temperature on the structure and catalytic activity of catalysts were investigated. Catalyst from nitrate precursor was also characterized to compare the influence of different precursors. The 6Mn4Ce sample from oxalate route sintered at 400 °C showed the maximum reaction rate of 0.50 mmol gcat−1h−1; T90 of the catalyst is 216 °C. The catalytic activity is related to surface area, pore size distribution, surface elemental species, particle size distribution and low temperature reducibility which may derived from synergistic effect between manganese and cerium oxide. Compared with nitrate precursors, catalyst from oxalate route can be more finely dispersed on the pores of silica without damaging the pore structure of support. The role of silica is not only a support, but also an in situ reaction site for precursor’s decomposition, which ensure the finely distribution of active components. In addition, the best catalyst showed good stability with prolonged time on stream.

Particulate matter (PM) from cooking has caused seriously indoor air pollutant and aroused risk to human health. It is urged to get deep knowledge of their spatial-temporal distribution of source emission characteristics, especially ultrafine particles (UFP