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101篇 您的检索式:作者名="Weng Duan"
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1Changes in intestinal mucosal immune barrier in rats with endotoxemia显示文摘AIM:To investigate the dysfunction of the immunological barrier of the intestinal mucosa during endotox-emia and to elucidate the potential mechanism of this dysfunction.METHODS:Male Wistar rats were randomly distributed into two groups:control group and lipopolysaccharide(LPS)group.Endotoxemia was induced by a single caudal venous injection of LPS.Animals were sacrifi ced in batches 2,6,12 and 24 h after LPS infusion.The number of microfold(M)-cells,dendritic cells(DCs),CD4+ T cells,CD8+ T cells,regulatory T(Tr)cells and IgA+ B cells in the intestinal mucosa were counted after immunohistochemical staining.Apoptotic lympho-cytes were counted after TUNEL staining.The levels of interleukin(IL)-4,interferon(IFN)-γ and forkhead box P3(Foxp3)in mucosal homogenates were measured by ELISA.The secretory IgA(sIgA)content in the total protein of one milligram of small intestinal mucus was detected using a radioimmunological assay.RESULTS:This research demonstrated that LPS-induced endotoxemia results in small intestinal mucosa injury.The number of M-cells,DCs,CD8+ T cells,and IgA+ B cells were decreased while Tr cell and apoptotic lymphocyte numbers were increased signifi cantly.The number of CD4+ T cells increased in the early stages and then slightly decreased by 24 h.The level of IL-4 significantly increased in the early stages and then reversed by the end of the study period.The level of IFN-γ increased slightly in the early stages and then decreased markedly by the 24 h time point.Level of Foxp3 increased whereas sIgA level decreased.CONCLUSION:Mucosal immune dysfunction forms part of the intestinal barrier injury during endotoxemia.The increased number and function of Tr cells as well as lymphocyte apoptosis result in mucosal immunodefi ciency.Chong Liu Ang Li Yi-Bing Weng Mei-Li Duan Bao-En Wang Shu-Wen Zhang 2009World Journal of Gastroenterology2009,15,46:35
2Low-temperature SCR activity and SO_2 deactivation mechanism of Ce-modified V_2O_5–WO_3/TiO_2 catalyst显示文摘The promotion effect of ceria modi fi cation on the low-temperature activity of V2O5-WO3/TiO2 catalyst was evaluated for the selective catalytic reduction of NO with NH3(NH3-SCR). The catalytic activity of 1 wt% V2O5-WO3/TiO2 was signi fi cantly enhanced by the addition of 8 wt%ceria, which exhibited a NO x conversion above 80% in a broad temperature range 190–450 1C. This performance was comparable with 3 wt%V2O5-WO3/TiO2, indicating that the addition of ceria contributed to reducing the usage of toxic vanadia in developing low-temperature SCR catalysts. Moreover, V1 Ce WTi exhibited approximately 10% decrease in NOx conversion in the presence of 60 ppm SO2. The characterization results indicated that active components of V, W and Ce were well dispersed on TiO2 support. The synergetic interaction between Ce and V species by forming V–O–Ce bridges enhanced the reducibility of VCe WTi catalyst and thus improved the low-temperature activity. The sulfur poisoning mechanism was also presented on a basis of the designed TPDC(temperature-programmed decomposition) and TPSR(temperatureprogrammed surface reaction) experiments. The deposition of(NH4)2SO4on V1 Ce WTi catalyst was much smaller compared with that on V1 Ti.On the other hand, the oxidation of SO2 to SO3was signi fi cantly promoted on the CeO2-modi fi ed catalyst, accompanied by the formation of cerium sulfates. Therefore, the deactivation of this catalyst was mainly attributed to the vanishing of the V–Ce interaction and the sulfation of active ceria.Ziran Ma Xiaodong Wu Ya Feng Zhichun Si Duan Weng Lei Shi 2015Progress in Natural Science:Materials International2015,25,4:29
3Effects of WOx modification on the activity, adsorption and redox properties of CeO_2 catalyst for NO_x reduction with ammonia显示文摘A series of WO3/CeO2 (WOx/CeO2) catalysts were synthesized by wet impregnation of ammonium metatungstate on a CeO2 support. The resulting solid acid catalysts were characterized by X-ray diffraction (XRD), UV-Vis spectroscopy (UV-Vis), Raman spectroscopy (Raman), in-situ Fourier transform infrared spectroscopy (in-situ FT-IR) of ammonia adsorption, NH3-TPD, H2 temperature-programmed reduction (H2-TPR), NH3/NO oxidation and activity measurements for NOx reduction by NH3 (NH3-SCR). The results show that polytungstate (WOx) species are the main species of tungsten oxide on the surface of ceria. The addition of tungsten oxide enhances the Bro¨nsted acidity of ceria catalysts remarkably and decreases the amount of surface oxygen on ceria, with strong interaction between CeO2 and WOx. As a result, the N2 selectivity of NH3 oxidation and NH3-SCR at high temperatures (> 300℃) is enhanced. Therefore, a wide working temperature window in which NOx conversion exceeds 80% (NOx conversion > 80%) from 200 to 450℃, is achieved over 10 wt.% WOx/CeO2 catalyst. A tentative model of the NH3-SCR reaction route on WOx/CeO2 catalysts is presented.Ziran Ma Duan Weng Xiaodong Wu Zhichun Si 2012Journal of Environmental Sciences2012,24,7:23
4Ectopic osteogenesis and angiogenesis regulated by porous architecture of hydroxyapatite scaffolds with similar interconnecting structure in vivo显示文摘The macro-pore sizes of porous scaffold play a key role for regulating ectopic osteogenesis and angiogenesis but many researches ignored the influence of interconnection between macro-pores with different sizes.In order to accurately reveal the relationship between ectopic osteogenesis and macro-pore sizes in dorsal muscle and abdominal cavities of dogs,hydroxyapatite(HA)scaffolds with three different macro-pore sizes of 500–650,750–900 and 1100–1250 mm were prepared via sugar spheres-leaching process,which also had similar interconnecting structure determined by keeping the d/s ratio of interconnecting window diameter to macro-pore size constant.The permeability test showed that the seepage flow of fluid through the porous scaffolds increased with the increase of macro-pore sizes.The cell growth in three scaffolds was not affected by the macro-pore sizes.The in vivo ectopic implantation results indicated that the macro-pore sizes of HA scaffolds with the similar interconnecting structure have impact not only the speed of osteogenesis and angiogenesis but also the space distribution of newly formed bone.The scaffold with macro-pore sizes of 750–900 mm exhibited much faster angiogenesis and osteogenesis,and much more uniformly distribution of new bone than those with othermacro-pore sizes.This work illustrates the importance of a suitable macro-pore sizes in HA scaffolds with the similar interconnecting structure which provides the environment for ectopic osteogenesis and angiogenesis.Jinyu Li Wei Zhi Taotao Xu Feng Shi Ke Duan JianxinWang Yandong Mu Jie Weng 2016Regenerative Biomaterials2016,3,5:16
5Effect of barium sulfate modification on the SO2 tolerance of V2O5/TiO2 catalyst for NH3-SCR reaction显示文摘Sulfur poisoning of V_2O_5/BaSO_4–TiO_2(VBT),V_2O_5/WO_3–TiO_2(VWT) and V_2O_5/BaSO_4–WO_3–TiO_2(VBWT) catalysts was performed in wet air at 350℃ for 3 hr,and activities for the selective catalytic reduction of NO_x with NH_3 were evaluated for 200–500℃.The VBT catalyst showed higher NO_x conversions after sulfur poisoning than the other two catalysts.The introduction of barium sulfate contributed to strong acid sites for the as-received catalyst,and eliminated the redox cycle of active vanadium oxide to some extent,which resulted in a certain loss of activity.Readily decomposable sulfate species formed on VBT-S instead of inactive sulfates on VWT-S.These decomposable sulfates increased the number of strong acid sites significantly.Some sulfate species escaped during catalyst preparation and barium sulfate was reproduced during sulfur poisoning,which protects vanadia from sulfur oxide attachment to a great extent.Consequently,the VBT catalyst exhibited the best resistance to sulfur poisoning.Tengfei Xu Xiaodong Wu Xuesong Liu Li Cao Qiwei Lin Duan Weng 2017Journal of Environmental Sciences2017,29,7:14
6Synergistic effect between ceria and tungsten oxide on WO_3-CeO_2-TiO_2 catalysts for NH_3-SCR reactionLei Chen Duan Weng Zhichun Si Xiaodong Wu 2012Progress in Natural Science:Materials International2012,22,4:11
7Highly active mixed-phase TiO_2 photocatalysts fabricated at low temperature and the correlation between phase composition and photocatalytic activity显示文摘The idea of varying volume ratio of water to ethanol in solvent was firstly employed to yield phase composition controllable mixedphase titanium dioxide (TiO2) photocatalysts via a low temperature solvothermal route at 353 K. It was found that anatase contents increase from 0 to 100% with increase of ethanol contents in solvent. The mixed-phase TiO2 with 60% anatase content exhibited the best photocatalytic activity in photodecomposing formaldehyde (FAD) under UV light irradiation, which increases by about 270 or 400% in comparison with single rutile or anatase TiO2, and is slightly better than commercial mixed-phase TiO2 (P25). The synergistic effect in mixed-phase TiO2 including antenna effect by rutile phase and the activation effect by anatase phase was observed. Further, partially quantitive correlation between phase composition and photocatalytic activity was ascribed to maximizing the synergistic effect and an optimal value of anatase content about 60% in mixed-phase TiO2 photocatalyst was therefore suggested.SHI, Lei WENG, Duan 2008Journal of Environmental Sciences2008,20,10:10
8Chemical deactivation of V2Os-WO3/Ti02 SCR catalyst by combined effect of potassium and chloride显示文摘Xiaodong WU Wenchao YU Zhichun SI Duan WENG 2013Frontiers of Environmental Science & Engineering2013,7,3:9
9Epidemiology of Sepsis-3 in a sub-district of Beijing: secondary analysis of a population-based database显示文摘Background: With the publication of Sepsis-3 definition, epidemiological data based on Sepsis-3 definition from middle-income countries including China are scarce, which prohibits understanding of the disease burden of this newly defined syndrome in these settings. The purpose of this study was to describe incidence and outcome of Sepsis-3 in Yuetan sub-district of Beijing and to estimate the incidence rate of Sepsis-3 in China. Methods: The medical records of all adult residents hospitalized from July 1, 2012 to June 30, 2014 in Yuetan sub-district of Beijing were reviewed. Patients with sepsis-3 and severe sepsis/septic shock were identified. The incidence rates and mortality rate of sepsis-3 and sepsis/septic shock were calculated, incidence rates and in-hospital mortality rates were normalized to the population distribution in the 2010 National Census. Population incidence rate and case fatality rate between sexes were compared with the Z test, as the data conformed to Poisson distribution. Results: Of the 21,191 hospitalized patients, 935 patients were diagnosed with Sepsis-3, and 498 cases met severe sepsis/septic shock criteria. The crude annual incidence rate of Sepsis-3 in Yuetan sub-district was 363 cases per 100,000 population, corresponding to standardized incidence rates of 236 cases per 100,000 population per year, respectively. The overall case fatality rate of Sepsis-3 was 32.0%, the crude population mortality rates of Sepsis-3 was 116 cases per 100,000 population per year, the standardized mortality rate was 67 cases per 100,000 population per year, corresponding to a speculative extrapolation of 700,437 deaths in China. The incidence rate and mortality rate of Sepsis-3 were significantly higher in males, elderly people, and patients with more comorbidities. The 62.1% of patients with Sepsis-3 had community-acquired infections, compared with 75.3% of infected patients without Sepsis-3 (P < 0.001). The most common infection in patients with Sepsis-3 was lower respiratory tract infection. When compared with patients with Sepsis-3, patients diagnosed as severe sepsis/septic shock were more likely to have higher case fatality rate (53.4% vs. 32.0%, P < 0.001) Conclusions: This study found the standardized incidence rate of 236 cases per 100,000 person-year for Sepsis-3, which was more common in males and elderly population. This corresponded to about 2.5 million new cases of Sepsis-3 per year, resulting in more than 700,000 deaths in China.Hong-Cheng Tian Jian-Fang Zhou Li Weng Xiao-Yun Hu Jin-Min Peng Chun-Yao Wang Wei Jiang Xue-Ping Du Xiu-Ming Xi You-Zhong An Mei-Li Duan Bin Du 2019Chinese Medical Journal2019,,17:9
10Hydrothermal and sulfur aging of CeTi/CeWTi catalysts for selective catalytic reduction of NOx with NH3显示文摘The CeO2-TiO2(CeTi)and CeO2/WO3-TiO2(CeWTi)catalysts were prepared by sol-gel method.The asprepared catalysts were hydrothermally treated at 760℃for 48 h in air containing 10 vol%H2O to obtain the hydrothermal aged catalysts.The sulfur aged catalysts were treated at 400℃with 100 ppm SO2,10%water vapor,air balance for 48 h and catalysts.The powder X-ray diffraction(XRD)and Raman results indicate that the crystallization of hydrothermal aged catalysts is more serious than sulfur aged catalysts.In addition,tungsten species can stabilize the CeTi catalyst from grain growth.According to the results of in situ diffuse reflectance infrared Fourier transform spectra(DRIFTS),temperatureprogrammed desorption of ammonia(NH3-TPD),H2 temperature-programmed reduction(H2-TPR)and ammonia oxidation,the aging process leads to loss of surface area,redox properties,surface acidities and surface ceria concentration,especially for the hyd rothermal aging.The NH3-NO/NO2 SCR perfo rmances of sulfur aged catalysts are better than that of hydrothermal aged catalysts.Compared with CeTi catalyst,the addition of tungsten inhibits the crystallization of catalyst.So that more acid sites and active sites are retained.This is also the reason why tungsten addition improves the NH3-NO/NO2 SCR performance of CeTi catalyst.Lei Chen Ding Wang Jiadao Wang Duan Weng Li Cao 2019Journal of Rare Earths2019,37,8:7
11Effects of Shuanghuanglian oral liquids on patients with COVID-19:a randomized,open-label,parallel-controlled,multicenter clinical trial显示文摘We conducted a randomized,open-label,parallel-controlled,multicenter trial on the use of Shuanghuanglian(SHL),a traditional Chinese patent medicine,in treating cases of COVID-19.A total of 176 patients received SHL by three doses(56 in low dose,61 in middle dose,and 59 in high dose)in addition to standard care.The control group was composed of 59 patients who received standard therapy alone.Treatment with SHL was not associated with a difference from standard care in the time to disease recovery.Patients with 14-day SHL treatment had significantly higher rate in negative conversion of SARS-CoV-2 in nucleic acid swab tests than the patients from the control group(93.4%vs.73.9%,P=0.006).Analysis of chest computed tomography images showed that treatment with high-dose SHL significantly promoted absorption of inflammatory focus of pneumonia,which was evaluated by density reduction of inflammatory focus from baseline,at day 7(mean difference(95%CI),−46.39(−86.83 to−5.94)HU;P=0.025)and day 14(mean difference(95%CI),−74.21(−133.35 to−15.08)HU;P=0.014).No serious adverse events occurred in the SHL groups.This study illustrated that SHL in combination with standard care was safe and partially effective for the treatment of COVID-19.Li Ni Zheng Wen Xiaowen Hu Wei Tang Haisheng Wang Ling Zhou Lujin Wu Hong Wang Chang Xu Xizhen Xu Zhichao Xiao Zongzhe Li Chene Li Yujian Liu Jialin Duan Chen Chen Dan Li Runhua Zhang Jinliang Li Yongxiang Yi Wei Huang Yanyan Chen Jianping Zhao Jianping Zuo Jianping Weng Hualiang Jiang Dao Wen Wang 2021Frontiers of Medicine2021,15,5:7
12Lung-protective Ventilation in Patients with Brain Injury: A Multicenter Cross-sectional Study and Questionnaire Survey in China显示文摘Xu-Ying Luo Ying-Hong Hu Xiang-Yuan Cao Yan Kang Li-Ping Liu Shou-Hong Wang Rong-Guo Yu Xiang-You Yu Xia Zhang Bao-Shan Li Zeng-Xiang Ma Yi-Bing Weng Heng Zhang De-Chang Chen Wei Chen Wen-Jin Chen Xiu-Mei Chen Bin Du Mei-Li Duan Jin Hu Yun-Feng Hoang Gui-Jun Jia Li-Hong Li Yu-Min Liang Bing-Yu Qin Xian-Dong Wang Jian Xiong Li-Mei Yan Zheng-Ping Yang Chen-Ming Dong Dong-Xin Wang Qing-Yuan Zhan Shuang-Lin FU Lin Zhao Qi-Bing Huang Ying-Guang Xie Xiao-Bo Huang Guo-Bin Zhang Wang-Bin Xu Yuan Xu YaLing Liu He-Ling Zhao Rong-Qing Sun Ming Sun Qing-Hong Cheng Xin Qu Xiao-Feng Yang Ming Xu Zhong-Hua Shi Han Chen Xuan He Yan-Lin Yang Guang-Qiang Chen Xiu-Mei Sun Jian-Xin Zhou 2016Chinese Medical Journal2016,,14:6
13Effect of water vapor on NH_3–NO/NO_2 SCR performance of fresh and aged MnO_x–NbO_x–CeO_2 catalysts显示文摘A MnOx–NbOx–CeO2 catalyst for low temperature selective catalytic reduction(SCR) of NOx with NH3 was prepared by a sol–gel method, and characterized by NH3–NO/NO2 SCR catalytic activity, NO/NH3 oxidation activity, NOx/NH3 TPD, XRD, BET, H2-TPR and in-situ Diffuse Reflectance Infrared Fourier Transform Spectroscopy(DRIFTS). The results indicate that the Mn Ox–Nb Ox–CeO2 catalyst shows excellent low temperature NH3-SCR activity in the temperature range of 150–300℃. Water vapor inhibits the low temperature activity of the catalyst in standard SCR due to the inhibition of NOx adsorption. As the NO2 content increases in the feed, water vapor does not affect the activity in NO2 SCR. Meanwhile, water vapor significantly enhances the N2 selectivity of the fresh and the aged catalysts due to its inhibition of the decomposition of NH4NO3 into N2O.Lei Chen Zhichun Si Xiaodong Wu Duan Weng Zhenwei Wu 2015Journal of Environmental Sciences2015,27,5:6
14Preparation and thermal stability of zirconia-doped mullite fibers via sol-gel methodWei WANG Duan WENG Xiao-dong WU 2011Progress in Natural Science:Materials International2011,21,2:6
15Optimizing the crystallinity and acidity of H-SAPO-34 by fluoride for synthesizing Cu/SAPO-34 NH_3-SCR catalyst显示文摘A series of H-SAPO-34 zeolites were synthesized by a hydrothermal method in fluoride media.The as-synthesized H-SAPO-34 zeolites were characterized by X-ray diffraction(XRD),scanning electron microscopy(SEM),N_2 physisorption,temperature-programmed desorption of NH_3(NH_3-TPD) and nuclear magnetic resonance(NMR) measurements.The results showed that a certain concentration of F- anions promoted the nucleation and crystallization of H-SAPO-34.The H-SAPO-34 synthesized in the fluoride media showed high crystallinity,uniform particle size distribution,large specific surface area and pore volume,and enhanced acidity.Therefore,Cu/SAPO-34 based on the fluoride-assisted zeolite showed a broadened temperature window for the selective catalytic reduction of NO by NH_3(NH_3-SCR) reaction due to the enhanced acidity of the zeolite and the improved dispersion of copper species.Jing Ma Zhichun Si Xiaodong Wu Duan Weng Yue Ma 2016Journal of Environmental Sciences2016,28,3:5
16Controlled pore size of Pt/KIT-6 used for propane total oxidation显示文摘Mesoporous silica KIT-6 with different pore sizes was controllably synthesized by hydrothermal methods. The same contents of Pt were loaded on KIT-6 supports to apply for propane total oxidation. Low-angle X-ray diffraction(XRD), nitrogen adsorption-desorption, CO chemisorption and transmission electron microscopy(TEM) were carried out to investigate the physicochemical properties of the catalysts. The results reveal that different pore sizes of KIT-6 supports could affect the Pt particle sizes on KIT-6. The mesopores on KIT-6-80 and KIT-6-130 effectively confine the size of the inside Pt nanoparticles during calcining. Pt/KIT-6-80 with the appropriate pore size as well as the Pt particle size exhibits the best catalytic performance with T_(50)(the temperature at which hydrocarbon(HC) conversion reaches 50%) of only 237 ℃. However, Pt particles prefer dispersing on the external surface of KIT-6-40 due to those too small pores.Yu-Sheng Chen Yi-Dan Cao Rui Ran Xiao-Dong Wu Duan Weng 2018Rare Metals2018,37,2:5
17Microstructure and oxygen storage capacity of Sr-modified Pt/CeO_2-ZrO_2 catalystsRui Ran a,Jun Fan b,Duan Weng a,a State Key Lab of New Ceramic and Fine Processing,Department of Materials Science and Engineering,Tsinghua University,Beijing 100084,China b The Administrative Centre for China’s Agenda 21,Beijing 100038,China 2012Progress in Natural Science:Materials International2012,22,1:5
18A novel insight into enhanced propane combustion performance on PtUSY catalyst显示文摘Platinum was supported on c-Al_2O_3 and ultrastable Y zeolite(USY) by an incipient wetness impregnation method. The catalysts were characterized by nitrogen physisorption, transmission electron microscopy(TEM),CO/C_3H_8 isothermal oxidations, NH_3 temperature-programmed desorption(NH_3–TPD) and infrared(IR) spectroscopy of adsorbed probe molecules(CO, C_3H_8 and C_3H_8+ O_2). Compared with Pt/Al_2O_3, Pt USY catalyst shows obviously higher activity for the combustion of propane. After estimating the size effect of Pt particles and propane adsorption capacity of USY, the excellent activity of Pt USY is also attributed to the strong interactions between the precious metal and the acidic zeolite. It inhibits the oxidation of Pt in an oxygen-rich atmosphere at high temperatures, which facilitate the initial oxidation step involving the C–H bond activation on metallic Pt as reflected by in situ diffuse reflectance infrared Fouriertransformed(DRIFT) spectra.Hui Luo Xiao-Dong Wu Duan Weng Shuang Liu Rui Ran 2017Rare Metals2017,36,1:5
19Advanced Radiative Transfer Modeling System(ARMS): A New-Generation Satellite Observation Operator Developed for Numerical Weather Prediction and Remote Sensing Applications显示文摘1.Urgent requirements for developing Feng Yun satellite observation operators In the past two decades,satellite measurements have been widely utilized for understanding and predicting weather and climate,and are now an essential component in global observing systems.Fuzhong WENG Xinwen YU Yihong DUAN Jun YANG Jianjie WANG 2020Advances in Atmospheric Sciences2020,37,2:4
20Comprehensive Proteomic Profiling of Patients'Tears Identifies Potential Biomarkers for the Traumatic Vegetative State显示文摘The vegetative state is a complex condition with unclear mechanisms and limited diagnostic, prognostic,and therapeutic methods. In this study, we aimed to explore the proteomic profile of tears from patients in a traumatic vegetative state and identify potential diagnostic markers using tears—a body fluid that can be collected noninvasively. Using i TRAQ quantitative proteomic technology, in the discovery phase, tear samples collected from 16 patients in a traumatic vegetative state and 16 normal individuals were analyzed. Among 1080 identified tear proteins, 57 were upregulated and 15 were downregulated in the patients compared to the controls. Bioinformatics analysis revealed that the differentially-expressed proteins were mainly involved in the wound response and immune response signaling pathways. Furthermore, we verified the levels of 7 differentially-expressed proteins in tears from50 traumatic vegetative state patients and 50 normal controls(including the samples used in the discovery phase) using ELISA. The results showed that this 7-protein panel had a high discrimination ability for traumatic vegetative state(area under the curve = 0.999). In summary, the altered tear proteomic profile identified in this study provides a basis for potential tear protein markers for diagnosis and prognosis of the traumatic vegetative state and also provides novel insights into the mechanisms of traumatic vegetative state.Qilin Tang Chao Zhang Xiang Wu Wenbin Duan Weiji Weng Junfeng Feng Qing Mao Shubin Chen Jiyao Jiang Guoyi Gao 2018Neuroscience Bulletin2018,34,4:3
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