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Woody perovskite-type catalysts are the sorts of porous catalysts with biomass morphology, in order to achieve the simultaneous purification of PM, NOx, CO, and HC. Among them, the ratio of adsorbed oxygen (Oads)/lattice oxygen (Olatt) of perovskite-type catalysts can be improved to avoid the collapse and aggregation of perovskite-type catalysts. The reason was attributed to the presence of a large number of high-energy electrons, active particles, and active heavy particles in non-thermal plasma (NTP). In addition, the NTP can outstandingly improve the specific surface area and porosity of catalysts. The NTP can enhance the four-way purification performance of PM, NOx, CO, and HC emitted by automobile exhausts over woody perovskite-type catalysts. Dielectric barrier discharge (DBD) can generate the NTP under atmospheric pressure conditions, indicating the broad application prospects in environmental protection and material processing. This study aims to enhance the performance of NTP synergistic woody perovskite-type catalysts, in order to purify the diesel engine exhaust. Firstly, a DBD reactor was designed, of which the corundum tubes and woody perovskite-type catalysts were used as the discharge medium. A two-dimensional simulation model was established for the DBD reactor. The plasma module of COMSOL software was employed to calculate the number density of active species under different parameter conditions of the reactor. After that, the optimal internal parameters of the reactor were obtained. Secondly, the overall mechanical structure of the non-thermal plasmawoody perovskite purifier was designed for the diesel engine exhaust. A numerical model was established to analyze the impact of different DBD arrangements on exhaust back pressure using pressure loss. Lastly, a test bench of the diesel engine was set to verify the purification performance of the purifier. According to the relevant regulations of automotive testing, the D2 (5 loads operating at rated speed) test cycle was selected from the ISO 8187 international standard, in order to test and verify the purifier. The model calculation indicated that when the input voltage of the exhaust purifier was 15 kV, the filling rate was 30%, the number density of active particles in the reactor reached the maximum, with an electron density of 1016/m3, the electron energy distribution in the reactor ranged from 101.1 to 101.5 eV, and the number densities of N2+, -CO, and -N2 reached 1018/m3, the number densities of -O reached 1013/m3, respectively. Once the number of DBD parallel connections was 20, and the DBD reactor length was 0.16 m, the exhaust back pressure of the purifier was 996.3 Pa. The experimental results showed that the exhaust back pressure of the purifier fully met the national standard requirements, in order to achieve the simultaneous purification of PM, NOx, CO, and HC. Furthermore, the purification efficiencies of the purifier reached 92%, 64%, 72%, and 61%, respectively, when the engine speed was 2 600r/min and the load was 50%. Once the purifier was used for no more than 75 h, the exhaust back pressure of the purifier was less than 3 kPa. Correlation analysis of experimental data revealed that the PM, CO and HC were promoted to reduce NOx, thus leading to the oxidation of PM, CO, and HC. The finding can provide the theoretical reference for synergistic catalysis in the field of automotive exhaust purification. [ABSTRACT FROM AUTHOR]

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The purpose of this paper is to study the performance of modified wood ceramics in removing ammonia nitrogen from water. The modified wood ceramic is a carb on-carbon composite material, which is made of pine wood as raw material, montmorillonite and magnesium chloride as modifiers, and calcined under nitrogen protection. The orthogonal experiment design was used to analyze the influence of various experimental parameters on the ammonia nitrogen adsorption capacity of the modified wood ceramics, and the significant factors affecting the ammonia nitrogen adsorption capacity were determined. The structure and properties of the modified wood ceramics were characterized by scanning electron microscope, X-ray diffraction, Fourier transform infrared spectroscopy and specific surface area. The results showed that the filling weight, the mass ratio of phenolic resin to anhydrous ethanol, the mass ratio of montmorillonite to anhydrous ethanol, the heating rate, the carbonization temperature, and the carbonization time had a significant effect on the ammonia nitrogen removal of the sample. The adsorption of ammonia nitrogen on the modified wood ceramics conforms to the quasi second order kinetic model. Freundlich isotherm can better fit the adsorption behavior of the modified wood ceramics. The open porosity of the prepared modified wood ceramics is 77.4%, the pore size distribution is mainly mesoporous, and the specific surface area is 12. 56 m²/g. The experiment shows that the modified wood ceramics can effectively remove ammonia nitrogen from water. [ABSTRACT FROM AUTHOR]

Copyright of China Forest Products Industry is the property of China Forest Products Industry Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Objective: To investigate the effect of levonorgestrel intrauterine contraceptive system combined with Guizhi Fuling capsule on sex hormone, blood lipid, serum high sensitive C-reactive protein (hs-CRP) and vascular endothelial growth factor (VEGF) levels in patients with adenomyosis. Methods: 90 patients with adenomyosis admitted to our hospital from April 2016 to December 2019 were divided into control group (n=45, treated with levonorgestrel intrauterine contraceptive system) and study group (n=45, treated with Guizhi Fuling capsule on the basis of the control group) according to the random number table. The efficacy, sex hormone, blood lipid and serum hs-CRP, VEGF levels, endometrial thickness, visual analogue scale (VAS) and adverse reactions of the two groups were compared. Results: 6 months after treatment, the total clinical effective rate of the study group was higher than that of the control group (P<0. 05). 6 months after treatment, follicle-stimulating hormone (FSH), hs-CRP, luteinizing hormone (LH), VEGF, endometrial thickness, and VAS scores of dysmenorrhea in both groups all decreased compared with those before treatment, and study group was lower than control group (P<0.05). Estradiol (E2) was higher than that before treatment, study group was higher than control group (P<0.05). There was no significant difference in total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C) and high-density lipoprotein cholesterol (HDL-C) in two groups at 6 months after treatment (P>0.05). There was no significant difference in the incidence of adverse reactions in two groups(P>0.05). Conclusion: Levonorgestrel intrauterine contraceptive system combined with Guizhi Fuling capsule is safe and effective in the treatment of adenomyosis, wihch can improve the sex hormone, serum hs-CRP, VEGF levels and endometrial thickness, reduce dysmenorrhea symptoms, and has a slight effect on the body's blood lipid. [ABSTRACT FROM AUTHOR]

Diesel engine is widely used in the fields of industrial and agricultural production and transportation for their good economy and dynamic performance. Unfortunately, diesel engines emit high quantities of particulate matter (PM) which is a potential risk to public health. Micron wood fiber is a kind of porous biological material that can be applied to filter PM emitted by diesel engine. In this paper, in order to increase the filtration efficiency and decrease filtration resistance, a wood fiber filter is developed, of which the internal structure is hollow and the external structure is like gear, and its advantages are low price, less requirement for diesel quality and large adsorption capacity for PM. In these respects, the gear-shaped wood fiber filter is promising in developing countries where the sulphur content is high in diesel oil. This gear-shaped wood fiber filter can be installed in a detachable DPF (diesel particle filter) whose temperature inside can be controlled below 220℃. First of all, based on the filter theory of fiber material, the filtration efficiency model of the gear-shaped wood fiber filter is established. Referring to the existing research and formula, the filtration efficiency of the gear-shaped wood fiber filter can be expressed by theoretical formula to be the function of wood fiber diameter, filling rate of wood fiber filter, thickness of filter and diameter of PM. Due to the diameter of PM ranging from 0.01 to 10 μm and mainly concentrating at around 0.1 μm, the recommended value of PM diameter is 0.1 μm. Then, through theoretical analysis and numerical calculation, the relationship curve between the filter efficiency and the influence factors is obtained. Lastly, a test bench of the filter performance is set up and used to verify the theoretical analysis results. In the test, we develope 10 gear-shaped wood fiber filters with different parameters according to the simulation results and set the speed and the load of the engine as 2 000 r/min and 50%. The results show that the experimental results are in good agreement with the theoretical results, i.e., the increasing of the filter thickness, the decreasing of the wood fiber diameter and the lowering of the filter filling rate will definitely improve the filtration efficiency of the gear-shaped wood fiber filter. For Lister Petter AA1 diesel engine, when the size of the DPF filter chamber is 140 mm in diameter and 150 mm in height, the filtration efficiency and the resistance of the filter with the wood fiber diameter of 15 μm, the filling rate of 0.3, the filter thickness of 12 mm are both in the most ideal range. At this point, the gear-shaped wood fiber filter has high efficiency and low exhaust resistance. When this filter works for 60 h from a new one, the filtration efficiency varies within a small range and the filtration state is relatively stable. When this filter works from 60 to 100 h, the filtration efficiency increases rapidly and reaches 96% at the end. However the filtration resistance exceeds the specified limit and a new wood fiber filter should replace the old one after it works for 100 h. Furthermore, the test results also show that the filtration efficiency of all filters made in test are more than 85%, which can meet the demand of the national standard of the diesel exhaust emission. [ABSTRACT FROM AUTHOR]

Gestational diabetes mellitus (GDM) is the most prevalent metabolic disorder disease during the gestation period. Exercise therapy has become one of the basic methods to control the development of GDM for its efficiency in controlling the maternal body mass, reducing the burden of the cardiovascular system, reducing the level of blood pressure and improving the oxygen reserve. At present about the form of exercise, intensity, duration and monitoring of the fetal during pregnancy is still controversial. The safety and comfortable excise is suitable for the pregnant women and load movement should be avoided in the late pregnancy. Normal women keep on moderate aerobic exercise 30 minutes per day during their pregnancy, pay attention to their fetal movement and uterine contraction during the exercise in order to determine whether exercise too much. Exercise therapy can reduce the incidence of GDMand control the progress of GDM. [ABSTRACT FROM AUTHOR]