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Effects of Bifidobacterium lactis BLa80 on fecal and mucosal flora and stem cell factor/c-kit signaling pathway in simulated microgravity rats

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World Journal of Gastroenterology 2025年第1期31卷 93-109页

作者： Ping Zhang Ying Zhu Pu Chen Tong Zhou Zhe-Yi Han Jun Xiao Jian-Feng Ma Wen Ma Peng Zang Ying Chen Graduate School Hebei North UniversityZhangjiakou 075000Hebei ProvinceChina Key Laboratory of Aerospace Nutrition and Food Engineering China Astronaut Research and Training CenterBeijing 100094China department of Gastroenterology The Air Force Medical CenterBeijing 100142China department of Blood Transfusion Air Force Medical CenterBeijing 100142China

BACKGROUND Simulated microgravity environment can lead to gastrointestinal motility *** pathogenesis of gastrointestinal motility disorders is closely related to the stem cell factor(SCF)/c-kit signaling pathway associated with intestinal flora and Cajal stromal ***,intestinal flora can also affect the regulation of SCF/c-kit signaling pathway,thus affecting the expression of Cajal stromal *** cells are the pacemakers of gastrointestinal *** To investigate the effects of Bifidobacterium lactis(***)BLa80 on the intestinal flora of rats in simulated microgravity and on the gastrointestinal motility-related SCF/c-kit *** The internationally recognized tail suspension animal model was used to simulate the microgravity environment,and 30 rats were randomly divided into control group,tail suspension group and drug administration tail suspension group with 10 rats in each group for a total of 28 *** tail group was given *** BLa80 by intragastric administration,and the other two groups were given water intragastric administration,the concentration of intragastric administration was 0.1 g/mL,and each rat was 1 mL/***&eosin staining was used to observe the histopathological changes in each segment of the intestine of each group,and the expression levels of SCF,c-kit,extracellular signal-regulated kinase(ERK)and p-ERK in the gastric antrum of each group were detected by Western blotting and *** fecal flora and mucosal flora of rats in each group were detected by 16S *** Simulated microgravity resulted in severe exfoliation of villi of duodenum,jejunum and ileum in rats,marked damage,increased space between villi,loose arrangement,shortened columnar epithelium of colon,less folds,narrower mucosal thickness,reduced goblet cell number and crypts,and significant improvement after probiotic *** microgravity reduced the expressions of SCF and c-kit,and increased the express

关键词： Simulated microgravity Rat Intestinal flora Gastrointestinal motility Stem cell factor/c-kit signaling pathway

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Catalytic reduction of NO_x by biomass-derived activated carbon supported metals

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Chinese Journal of Chemical Engineering 2018年第10期26卷 2077-2083页

作者： Yun Shu Fan Zhang Fan Wang Hongmei Wang Research Center of air pollution control Technology Chinese Research Academy of Environmental Sciences

In this study,to prepare a series of activated carbon-supported metals for the catalytic reduction of NO_x to N_2 in excess O_2,activated carbons derived from lignocellulosic and herbaceous biomasses were selected as the reducing agents,and alkali and transition metals were used as the catalytic active *** effects of the type of biomass,carbonization temperature and catalyst composition on NO_x reduction efficiency were analyzed in a fixed-bed flow *** results showed that two temperature regimes are present for the NO_x-carbon reaction:at temperatures below 250°C,the NO_x adsorption process on the carbon surface was predominant,whereas true NO_x reduction by carbon occurred at temperatures above 250°C,producing N_2,CO_2 and *** influence of the carbonization temperature on carbon reactivity depended on the effect of the carbonization temperature on the carbon surface area and the reduction of the metal species on *** studied metals catalyzed both NO_xand O_2reduction by carbon,and potassium could strongly enhance the C-NO_x reaction without substantial carbon consumption by O_***,the potassium supported by sawdust-derived activated carbon exhibited higher selectivity and capacity towards NO_x reduction than did its previously reported coal-derived *** properties were ascribed to the high dispersion of the active potassium species on the carbon surface,as observed through the comparison of X-ray photoelectron spectroscopy and powder X-ray diffraction results for the carbons made from biomass and coal-based precursors.

关键词： Biomass NOx reduction Activated carbon Selectivity

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Evaluating the emission status of light-duty gasoline vehicles and motorcycles in Macao with real-world remote sensing measurement

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Journal of Environmental Sciences 2014年第11期26卷 2240-2248页

作者： Yu Zhou Ye Wu Shaojun Zhang Lixin Fu Jiming Hao School of Environment State Key Joint Laboratory of Environment Simulation and Pollution Control Tsinghua University State Environmental Protection Key Laboratory of Sources and control of air pollution Complex

Roadside remote sensing measurement was used to explore the real-world emission status of light duty gasoline vehicles （LDGVs） and motorcycles in Macao. Both fuel-based and distance-based emission factors were derived using the mass balance method. The emission concentration profile of LDGVs illustrated the benefits of tightening emission standards at the source country or region of import. The distance-based emission factors for CO, HC and NOx of LDGVs registered before 2000 were 8.00, 1.04 and 1.36 g/km, respectively. The distance-based emission factors for CO, HC and NOx of LDGVs registered in or after 2000 were 1.16, 0.15 and 0.18 g/km, respectively. The fuel-based CO emission factors of light duty motorcycles （LDMCs） and heavy duty motorcycles （HDMCs） registered before 2000 were about 10 times higher than those of LDGVs of the same age group. As the emissions of LDGVs decreased more quickly after 2000, the gap widens for newer vehicles. The distance-based HC emission factors of LDMCs and HDMCs registered before 2000 were 4.81 and 2.91 g/km, respectively. The distance-based HC emission factors of LDMCs and HDMCs registered in or after 2000 were 3.52 and 0.93 g/km, respectively. The poor emission performance of motorcycles and their larger share in the traffic flow will cause them to be the major contributor to traffic CO and HC emissions. LDMCs, especially two-stroke models, should be the priority for vehicle emission control efforts in Macao.

关键词： Emission Remote sensing Macao Motorcycle

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Product yields of stabilized Criegee intermediates in the ozonolysis reactions of cis-2-butene, 2-methyl-2-butene, cyclopentene, and cyclohexene

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Science China Chemistry 2018年第7期61卷 850-856页

作者： Mixtli Campos-Pineda Jingsong Zhang department of Chemistry and air pollution Research Center University of California

Cavity ring-down spectroscopy(CRDS)was utilized in combination with chemical titration with sulfur dioxide(SO_2)to quantify stabilized Criegee intermediates(s CIs)produced at low pressures(4–20 Torr)in ozonolysis reactions of cis-2-butene,2-methyl-2-butene,cyclopentene,and *** yield of stabilized s CI,acetaldehyde oxide(CH_3CHOO),from cis-2-butene ozonolysis decreased with decreasing pressure and reached to 0.05±0.04 at the zero-pressure *** nonsymmetric alkene 2-methyl-2-butene produced two stabilized s CIs,CH_3CHOO and acetone oxide((CH_3)_2COO),and their total yield decreased with decreasing pressure and reached 0.01±0.03 at the zero-pressure *** cyclopentene and cyclohexene,the s CI yields were essentially constant near zero,as expected of endocyclic *** nascent yields of s CI of various alkenes are compared.

关键词： ozonolysis stabilized Criegee intermediates cavity ring-down spectroscopy

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Temporal and spatial characteristics of PM_(2.5) transport fluxes of typical inland and coastal cities in China

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Journal of Environmental Sciences 2021年第5期33卷 229-245页

作者： Panbo Guan Xiaoqi Wicmg Shuiyuan Cheng Hanyu Zhang Key Laboratory of Beijing on Regional air pollution control Beijing University of TechnologyBeijing100124China

Local pollution and the cross-boundary transmission of pollutants between cities have an inevitable impact on the atmosphere. Quantitative assessments of the contribution of transport to pollution in inland and coastal cities are necessary for the implementation of practical, regional, and joint emission control strategies. In this study, the Comprehensive air Quality Model(CAMx), together with the Weather Research and Forecasting model(WRF), was used to simulate the contributions to pollution of different cities in 2016. The monthly inflow, outflow, and net flux from the ground to the extended layers served as the three main indicators for the analysis of the interactions of PM_(2.5) transport between adjacent cities. Between inland and coastal cities, the magnitude of inflow and outflow are larger in the former than in the latter. The inflow flux in the inland cities(Beijing and Shijiazhuang) was 10.6 and 10.7 kt/day, respectively, while that in the coastal cities(Tianjin, Shanghai, Hefei, Nanjing, and Hangzhou) was 9.1, 3.3, 5.8, 4.4, and 3.7 kt/day, respectively. In terms of variation over the year, the strongest inflow in the BTH region occurred in April, followed by October, July, and January, while that in the coastal cities in YRD occurred in January, followed by October, April, and July. Therefore, based on the flux intensity calculations and the transport flux pathways, effective joint control measures can be provided with scientific support, and a better understanding of the evolutionary mechanism among inland and coastal cities can be acquired.

关键词： PM_(2.5)flux modeling system regional transport inland cities coastal cities

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Excellent performance of Cu-Mn/Ti-sepiolite catalysts for low-temperature CO oxidation

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Frontiers of Environmental Science & Engineering 2017年第2期11卷 77-86页

作者： Yong Song Lisha Liu Zhidan Fu Qing Ye Shuiyuan Cheng Tianfang Kang Hongxing Dai Key Laboratory of Beijing on Regional air pollution control Department of Environmental Science Beijing University of Technology Beijing 100124 China Beijing Key Laboratory for Green Catalysis and Separation Key Laboratory of Beijing on Regional Air Pollution Control Department of Chemistry and Chemical Engineering Beijing University of Technology Beijing 100124 China

The Ti-modified sepiolite （Ti-Sep）-supported Mn-Cu mixed oxide （yMn5Cu/Ti-Sep） catalysts were synthesized using the co-precipitation method. The materials were characterized by the X-ray diffraction scanning electron microscope, N2 adsorption-desorption, H2-TPR, O2-TPD, and XPS techniques, and their catalytic activities for CO oxidation were evaluated. It was found that the catalytic activities ofyMn5Cu/Ti-Sep were higher than those of 5Cu/Ti-Sep and 30Mn/Ti-Sep, and the Mn/Cu molar ratio had a distinct influence on catalytic activity of the sample. Among the yMn5Cu/Ti- Sep samples, the 30Mn5Cu/Ti-Sep catalyst showed the best activity （which also outperformed the 30Mn5Cu/Sep catalyst）, giving the highest reaction rate of 0.875 × 10^- 3 mmol· g^-1· s^-1 and the lowest T50%and T100% of 56℃ and 86℃, respectively. Moreover, the 30Mn5Cu/Ti-Sep possessed the best low-temperature reducibility, the lowest 02 desorption temperature, and the highest surface Mn3＋/ Mn4＋ atomic ratio. It is concluded that factors, such as the strong interaction between the copper or manganese oxides and the Ti-Sep support, good low-temperature reducibility, and good mobility of ehemisorbed oxygen species, were responsible for the excellent catalytic activity of 30Mn5Cu/Ti-Sep.

关键词： Ti-modified sepioliteSupported Mn-Cu mixed oxideLow-temperature reducibilityStrong metal-support interactionCO oxidation

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Surface reactive species on MnO_x(0.4)-CeO_2 catalysts towards soot oxidation assisted with pulse dielectric barrier discharge

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Journal of Rare Earths 2014年第2期32卷 153-158页

作者：付名利林俊敏朱文波吴军良陈礼敏黄碧纯叶代启 College of Environment and Energy South China University of Technology Guangdong Provincial Key Laboratory of Atmospheric Environment and pollution control Guangdong High Education Engineering Technology Research Center for air pollution control Key Lab of Ministry of Education for pollution control and Ecosystem Restoration in Industry Clusters

MnOx（0.4）-CeO2 was investigated for soot oxidation assisted with a pulse dielectric barrier discharge （DBD）. The catalysts were evaluated and characterized with TPO （temperature programmed oxidation）, X-ray diffraction （XRD）, Raman and X-ray photo- electron spectroscopy （XPS）. The ignition temperature Ti for soot oxidation decreased from 240.8 to 216.4 ℃ with the increase of the pulse DBD frequencies from 50 to 400 Hz, lower than that of the case without pulse DBD present （253.4 ℃）. The results of XRD, Raman and XPS agreed well with the TPO activities of MnOx（0.4）-CeO2 towards soot oxidation. More solid solution of ceria and manganese, and surface reactive species including 02 , O and Mn4＋ were responsible for the enhancement of soot oxidation due to pulse DBD injection in the present study. For solid solution favors to the activation and transformation of those species, which are be- lieved to be involved in the soot oxidation in a hybrid catalysis-plasma.

关键词： diesel soot MnOx(0.4)-Ce02 pulse dielectric barrier discharge reactive species rare earths

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Differentiated emission control strategy based on comprehensive evaluation of multi-media pollution:Case of mercury emission control

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Journal of Environmental Sciences 2023年第1期123卷 222-234页

作者： Dongwei Lv Qingru Wu Daiwei Ouyang Minneng Wen Gehui Zhang Shuxiao Wang Lei Duan State Key Laboratory of Environmental Simulation and pollution control School of EnvironmentTsinghua UniversityBeijing 100084China State Environmental Protection Key Laboratory of Sources and control of air pollution Complex Beijing 100084China

In order to comprehensively evaluate the environmental impact of multi-media mercury pollution under differentiated emission control strategies in China,a literature review and case studies were carried *** human exposure to methylmercury was assessed through the dietary intake of residents in areas surrounding a typical coal-fired power plant and a zinc(Zn)smelter,located either on acid soil with paddy growth in southern China,or on alkaline soil with wheat growth in northern *** with knowledge on speciated mercury in flue gas and the fate of mercury in the wastewater or solid waste of the typical emitters applying different air pollution control devices,a simplified model was developed by estimating the incremental daily intake of methylmercury from both local and global *** indicated that air pollution control for coal-fired power plants and Zn smelters can greatly reduce health risks from mercury pollution,mainly through a reduction in global methylmercury exposure,but could unfortunately induce local methylmercury exposure by transferring more mercury from flue gas to wastewater or solid waste,then contaminating surrounding soil,and thus increasing dietary intake via ***,tightening air emission control is conducive to reducing the comprehensive health risk,while the environmental equity between local and global pollution control should be fully *** in the south tends to have higher bioconcentration factors than wheat in the north,implying the great importance of strengthening local pollution control in the south,especially for Zn smelters with higher contribution to local pollution.

关键词： Mercury emission Methylmercury Heavy metal Bioconcentration factor Estimated daily intake Health risk assessment

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Characteristics of ozone and ozone precursors(VOCs and NOx) around a petroleum refinery in Beijing, China

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Journal of Environmental Sciences 2014年第2期26卷 332-342页

作者： Wei Wei Shuiyuan Cheng Guohao Li Gang Wang Haiyang Wang department of Environmental Science and Engineering Beijing University of Technology State Environmental Protection Key Laboratory of Sources and control of air pollution Complex Tsinghua University

A field measurement campaign for ozone and ozone precursors （VOCs and NOx） was conducted in summer 2011 around a petroleum refinery in the Beijing rural region. Three observation sites were arranged, one at southwest of the refinery as the background, and two at northeast of the refinery as the downwind receptors. Monitoring data revealed the presence of serious surface 03 pollution with the characteristics of high average daily mean and maximum concentrations （64.0 and 145.4 ppbV in no-rain days, respectively） and multi-peak diurnal variation. For NOx, the average hourly concentrations of NO2 and NO were in the range of 20.546.1 and 1.8-6.4 ppbV, respectively. For VOC measurement, a total of 51 compounds were detected. Normally, TVOCs at the background site was only dozens of ppbC, while TVOCs at the downwind sites reached several hundreds of ppbC. By subtracting the VOC concentrations at background, chemical profiles of VOC emission from the refinery were obtained, mainly including alkanes （60.0% ± 4.3%）, alkenes （21.1% ± 5.5%） and aromatics （18.9% ±3.9%）. Moreover, some differences in chemical profiles for the same measurement hours were observed between the downwind sites; the volume ratios of alkanes with low reactivity and those of alkenes with high reactivity respectively showed an increasing trend and a decreasing trend. Finally, based on temporal and spatial variations of VOC mixing ratios, their photochemical degradations and dispersion degradations were estimated to be 0.15-0.27 and 0.42-0.62, respectively, by the photochemical age calculation method, indicating stronger photochemical reactions around the refinery.

关键词： ozone volatile organic compounds (VOCs) photochemical degradations petroleum refinery

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Catalytic combustion of VOCs on Pt/CuMnCe and Pt/CeY honeycomb monolithic catalysts

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Journal of Rare Earths 2018年第12期36卷 1272-1277页

作者： Anming Zhu Ying Zhou Yue Wang Qiulian Zhu Huayan Liu Zekai Zhang Hanfeng Lu Innovation Team of air pollution control College of Chemical Engineering Institute of Catalytic Reaction Engineering Zhejiang University of Technology

The metal oxides CuMnCe and CeY washcoats on cordierite were prepared using an impregnation method, and then used as support for the active Pt component to prepare the Pt/CuMnCe and Pt/CeY monolithic catalysts for the deep oxidation of VOCs. In comparison with the Pt/CeY, CuMnCe, and CeY monolithic catalysts, the Pt/CuMnCe monolithic catalyst shows an excellent performance for toluene,ethyl acetate,and n-hexane oxidation and the Tis low to 216, 200 and 260 ℃,respectively. The active components Pt/PtO and CuMnCe result in a better synergetic interaction, which promote the catalyst reducibility, increase the oxygen mobility, and enhance the adsorption and activation of organic molecules.

关键词： Catalytic combustion Volatile organic compounds Monolithic catalysts Pt catalyst Cu-Mn-Ce mixed oxides

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