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Hydrothermal Treatment of Sol-Gel TiO_2 Film 被引量:1
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作者 Shaohua Zhang Bing Xie +1 位作者 fengyi li Tude Zou 《稀有金属材料与工程》 SCIE EI CAS CSCD 北大核心 2006年第A03期570-571,共2页
The preparation of TiO_2 film has been an important research area.In our work,we obtained the TiO_2 film by hydrothermal treating the amorphous film prepared by sol-gel method or the hydrolysis of titanium alkoxide.Th... The preparation of TiO_2 film has been an important research area.In our work,we obtained the TiO_2 film by hydrothermal treating the amorphous film prepared by sol-gel method or the hydrolysis of titanium alkoxide.The influence of temperature and duration time on the film properties was investigated.The photo degradation of methyl orange in aqueous solution of the film was studied.The films were characterized by XRD and Uv-Vis spectroscope. 展开更多
关键词 TITANIA FILM HYDROTHERMAL SOL-GEL
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Preparation of Carbon Nanotubes from Methane on Ni/Cu/Al Catalyst 被引量:1
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作者 Renzhong Wei fengyi li YaH Ju 《Journal of Natural Gas Chemistry》 EI CAS CSCD 2005年第3期173-176,共4页
A series of Ni/Cu/Al catalyst samples were prepared by the co-precipitation method. Carbon nanotubes with large inner diameters are successfully synthesized from methane on Ni/Cu/Al catalyst by adding sodium carbonate... A series of Ni/Cu/Al catalyst samples were prepared by the co-precipitation method. Carbon nanotubes with large inner diameters are successfully synthesized from methane on Ni/Cu/Al catalyst by adding sodium carbonate. The effects of the copper content and amounts of sodium carbonate on the morphology and microstructures of carbon nanotubes were investigated by CO adsorption and TEM technique. The experimental results showed that copper can influence both the catalytic activity and catalyst life. Best result was obtained when the copper content was 15%. Addition of sodium carbonate favors the formation of carbon nanotubes with large inner diameters. The growth mechanism of carbon nanotubes with large inner diameter is discussed. 展开更多
关键词 carbon nanotubes nickel/copper/aluminum catalyst PREPARATION METHANE co-precipitation
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Preparation of Nano-Sized TiO_2 Particles by Microemulsion Method 被引量:1
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作者 Shaohua Zhang Bing Xie +1 位作者 fengyi li Peng Xu 《稀有金属材料与工程》 SCIE EI CAS CSCD 北大核心 2006年第A03期575-577,共3页
Nano-sized titania powders have been prepared by hydrolysis of tetrabutyl titanate in the droplet of water/OP-7/pentanol/cyclohexane microemulsion system.The effects of ingredient change on the water drop size and par... Nano-sized titania powders have been prepared by hydrolysis of tetrabutyl titanate in the droplet of water/OP-7/pentanol/cyclohexane microemulsion system.The effects of ingredient change on the water drop size and particle size were investigated.The prepared TiO_2 was in the form of anatase after annealing.TiO_2 was characterized by TG-TGA, FTIR,XRD to measure the transformation temperature,surface adsorption and average size. 展开更多
关键词 TIO2 MICROEMULSION NANO
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Quantum Dynamics Calculations on Isotope Effects of Hydrogen Transfer Isomerization in Formic Acid Dimer
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作者 fengyi li Xiaoxi liu +2 位作者 Xingyu Yang Jianwei Cao Wensheng Bian 《Chinese Journal of Chemical Physics》 SCIE EI CAS CSCD 2023年第5期545-552,I0001,共9页
We present a quantum dynamics study on the isotope effects of hydro-gen transfer isomerization in the formic acid dimer,and this is achieved by multidimensional dy-namics calculations with an efficient quantum mechani... We present a quantum dynamics study on the isotope effects of hydro-gen transfer isomerization in the formic acid dimer,and this is achieved by multidimensional dy-namics calculations with an efficient quantum mechanical theoretical scheme developed by our group,on a full-dimensional neural network ab initio potential energy surface.The ground-state and fundamental tun-neling splittings for four deuterium isotopologues of formic acid dimer are considered,and the calculated results are in very good general agreement with the avail-able experimental measurements.Strong isotope effects are revealed,the mode-specific funda-mental excitation effects on the tunneling rate are evidently influenced by the deuterium sub-stitution of H atom with the substitution on the OH bond being more effective than on the CH bond.Our studies are helpful for acquiring a better understanding of isotope effects in the double-hydrogen transfer processes. 展开更多
关键词 Quantum dynamics ISOMERIZATION Isotope effect Tunneling splitting Double hydrogen transfer
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Low Temperature Direct Synthesis of Strontium Titanate Powder
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作者 Bing Xie Shaohua Zhang +1 位作者 fengyi li Yumei Wu 《稀有金属材料与工程》 SCIE EI CAS CSCD 北大核心 2006年第A03期556-558,共3页
Low temperature direct synthesis (LTDS) involves the preparation of a base solution of Sr^(2+),and the mixing of base solution with tetrabutyl titanate solution.LTDS is an advantageous method because it does not requi... Low temperature direct synthesis (LTDS) involves the preparation of a base solution of Sr^(2+),and the mixing of base solution with tetrabutyl titanate solution.LTDS is an advantageous method because it does not require the complex hydrothermal facilities and it can prevent the agglomeration in calcinations of other liquid methods.In our work,we adopted LTDS method to prepare the nano strontium titanate powders,and characterize them by XRD,FT-IR and TGA.The influences of preparation temperature and solvents on grain size and lattice parameters were investigated.The results show that preparation temperature can slightly change the lattice parameters of grain,while solvents also play important roles in the preparation. 展开更多
关键词 SRTIO3 low temperature direct synthesis nano powder
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Clinical outcomes of cessation of nucleoside/nucleotide analogues in Chinese patients with HBeAg-negative chronic hepatitis B
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作者 fengyi li Yadong Zhang +3 位作者 Chao liu Juan li Dali Zhang Yinjie Gao 《iLIVER》 2024年第2期22-27,共6页
Background and aims:Cessation of nucleoside/nucleotide analogue(Nuc)therapy in patients with HBeAg-negative chronic hepatitis B(CHB)remains controversial.Methods:In this prospective,single-center cohort study,we recru... Background and aims:Cessation of nucleoside/nucleotide analogue(Nuc)therapy in patients with HBeAg-negative chronic hepatitis B(CHB)remains controversial.Methods:In this prospective,single-center cohort study,we recruited 45 patients with HBeAg-negative CHB from The Fifth Medical Center of Chinese People's Liberation Army General Hospital in China's Mainland.Patients were classified into a Nuc cessation group(n?27)and Nuc continuation group(n?18)and followed-up for 36 months.Nuc were stopped after being inactive for at least 4 years(normal alanine aminotransferase(ALT),undetectable hepatitis B virus(HBV)DNA),with liver fibrosisStage1(S1)and inflammationGrade(G1).Results:Within 3 years of follow-up,51.9%patients with Nuc cessation had virological relapse and 14.8%had ALT elevation,while all patients with Nuc continuation had undetectable HBV DNA and normal ALT.The rate of HBsAg loss after Nuc cessation was 22.2%compared with no seroconversion in patients with Nuc continuation.The hepatitis flare rate was 11.1%and there were no cases of hepatic decompensation after Nuc cessation.End of treatment(EOT)HBsAg,HBV RNA,and decline in HBV core-related antigen(HBcrAg)rate were predictive markers for HBsAg seroconversion at 6 months post-Nuc cessation.Conclusion:This study showed favorable HBsAg loss and low hepatitis flare rates after Nuc cessation.EOT HBsAg,HBV RNA,and decline in HBcrAg rate were predictive markers for HBsAg seroconversion at 6 months post-Nuc cessation. 展开更多
关键词 Nucleoside analogues Nucleotide analogues Therapy cessation HBeAg-negative Clinical relapse
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Guidance for the clinical evaluation of traditional Chinese medicine-induced liver injury Issued by China Food and Drug Administration 被引量:24
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作者 Xiaohe Xiao Jianyuan Tang +14 位作者 Yimin Mao Xiuhui li Jiabo Wang Chenghai liu Kewei Sun Yong’an Ye Zhengsheng Zou Cheng Peng ling Yang Yuming Guo Zhaofang Bai Tingting He Jing Jing fengyi li Na An 《Acta Pharmaceutica Sinica B》 SCIE CAS CSCD 2019年第3期648-658,共11页
1. Introduction Drug-induced liver injury (DILI), defined as liver injury caused by a drug and/or its metabolites, is a common clinical adverse drug reaction1–4. This type of injury can cause acute liver failure and ... 1. Introduction Drug-induced liver injury (DILI), defined as liver injury caused by a drug and/or its metabolites, is a common clinical adverse drug reaction1–4. This type of injury can cause acute liver failure and even death in severe cases5. 展开更多
关键词 TCM PTA GUIDANCE for the clinical evaluation of traditional Chinese medicine-induced liver injury Issued by China Food and Drug ADMINISTRATION China
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Effects of Angelica sinensis extracts on lipid oxidation in fish feeds and growth performance of juvenile Jian carp(Cyprinus carpio var. Jian) 被引量:3
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作者 Huatao li Dandan Yang +8 位作者 Zhihao li Mingquan He fengyi li Jun Jiang Siyi Tang Peiyuan Peng Wenhao Du Yuting Ma Ying liu 《Animal Nutrition》 SCIE 2019年第1期109-114,共6页
The study was to explore the effect of the extracts of Angelica sinensis(EAs) on lipid oxidation in fish feeds compared with ethoxyquin(EQ) and the effect of dietary EAs on growth performance of carp(Cyprinus carpio v... The study was to explore the effect of the extracts of Angelica sinensis(EAs) on lipid oxidation in fish feeds compared with ethoxyquin(EQ) and the effect of dietary EAs on growth performance of carp(Cyprinus carpio var. Jian). Firstly, fish feeds were respectively added with EQ, and ethyl ether extract ethyl acetate extract(EAE), acetone extract, ethanol extract(EE) and aqueous extract(AQE) of Angelica sinensis, except for the control. The results showed that EAs and EQ inhibited lipid oxidation in fish feed(P < 0.05). Of all of the examined EAs, EAE showed the strongest protective effects against lipid oxidation(P < 0.05). Moreover, EAE at high concentrations showed a stronger effect on lipid oxidation compared with EQ(P < 0.05). Then, 7 experimental diets respectively supplemented with 0.0, 1.0, 2.0, 3.0, 4.0, 5.0 and 6.0 g/kg of EAE were fed to the respective treatment groups for 30 d. Four replicates were performed for each treatment group; 20 carp(mean weight: 12.10 ± 0.13 g) were in each replicate. The result indicated that dietary EAE improved the growth performance in carp(P < 0.05). The appropriate con centration of EAE for carp growth was estimated to be 3.643 g/kg diet. Thus, EAE could be used as a natural antioxidant in feeds for Jian carp. 展开更多
关键词 Angelica sinensis EXTRACTS Ethoxyquin Lipid oxidation Growth performance
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Clinical Epidemiology,Illness Profiles,and the Implication of COVID-19 Before and After the Nationwide Omicron Outbreak During the Winter of 2022
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作者 Yuming Guo Zhe Xu +34 位作者 Wen-Xin Wang Cheng Zhen Jinhua Hu Jinsong Mu Chengcheng Ji Xin Yuan Ruonan Xu Lei Huang Lei Shi Fanping Meng Junliang Fu Shuangnan Zhou Siyu Wang fengyi li Bo Tu Dawei Zhang Huihuang Huang Yufeng Mao Wen Xu Chao Zhang Xiuying Mu Jun Zhao Bo Jin Haibin Su Yinying Lu Yongqian Cheng Dong Ji Shaoli You Jinghui Dong Changchun liu Mengmeng Zhang Yuanyuan li Tianjun Jiang Yonggang li Fu-Sheng Wang 《Infectious Diseases & Immunity》 CSCD 2023年第4期176-185,共10页
China.In this study,we aimed to investigate the clinical characteristics and outcomes of patients with coronavirus disease 2019(COVID-19)in the Beijing region.Methods:In this retrospective study,we enrolled inpatients... China.In this study,we aimed to investigate the clinical characteristics and outcomes of patients with coronavirus disease 2019(COVID-19)in the Beijing region.Methods:In this retrospective study,we enrolled inpatients admitted for COVID-19 in the Fifth Medical Center of Chinese PLA General Hospital in Beijing between November 10,2022,and January 30,2023.Demographic and clinical features and treatment outcomeswere comprehensively analyzed.We used logistic regression and linear regression analyses to explore the risk factors associated with disease severity and time of nucleic acid conversion,respectively.Results:A total of 1010 hospitalized patients with COVID-19 were enrolled.The median age was 43.0 years(interquartile range,28.0–63.0),and patients aged<60 years and≥60 years comprised 71.2%and 28.8%of total included patients,respectively.The clinical classification of mild(74.6%,753/1010),moderate(21.0%,212/1010),severe(2.7%,27/1010),and unidentified(1.8%,18/1010)was separately recorded;1005 patients were discharged,and 5 patients died in the hospital.The outbreak of the emerging epidemic witnessed an evident increase in the proportion of moderate(42.9%vs.16.4%)and severe(10.3%vs.1.1%)cases after December 7,2022.Patients with a moderate/severe classification had higher levels of procalcitonin,IL-6,serum ferritin,C-reactive protein,lactic dehydrogenase,serum urea nitrogen,and D-dimer and lower counts of CD4+T,CD8+T,and B cells(all P<0.001).Multivariable regression analysis revealed that increased odds of disease severity were associated with the following factors:age≥60 years,IL-6>7 pg/mL,lactic dehydrogenase level>245 U/L,cough,and fever at admission.Age≥80 years and chronic lung diseasewere independent risk factors in the nonmild group in elderly patients.In addition,the duration for nucleic acid to turn negativewas approximately 5.0 d(interquartile range,3.0–7.0).Prolonged time of nucleic acid conversion was associated with age≥60 years,serum urea nitrogen level>8.2 mmol/L,neutrophil count>7×10^(9)/L,and the presence of a chronic lung disease or carcinoma.Finally,unvaccinated patients accounted for 37.3%of enrolled patients;children and the elder people accounted for approximately half of that.The univariable analysis found that booster doses reduced disease severity and shortened the time of nucleic acid conversion in elderly patients.Conclusions:The outbreak ofOmicron rapidly increased the number of patientswith COVID-19 in Beijing.In elderly patients,booster doses may reduce disease severity and shorten the time of nucleic acid conversion.Healthcare systems should be optimized before an emerging epidemic outbreak. 展开更多
关键词 Beijing COVID-19 Disease severity ELDERLY Nucleic acid conversion Omicron variant
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Regioselective umpolung addition of dicyanobenzene to α,β-unsaturated alkenes enabled by electrochemical reduction 被引量:1
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作者 Sheng Zhang Wenchao Gao +5 位作者 Jianxue Shi Jingjing li fengyi li Yating liang Xuan Zhan Man-Bo li 《Organic Chemistry Frontiers》 SCIE EI 2022年第5期1261-1266,共6页
An umpolung addition of dicyanobenzene toα,β-unsaturated alkenes has been developed using an elec-troreductive strategy.This electrochemical protocol is well compatible with a broad range of convention-ally challeng... An umpolung addition of dicyanobenzene toα,β-unsaturated alkenes has been developed using an elec-troreductive strategy.This electrochemical protocol is well compatible with a broad range of convention-ally challenging substrates,includingα,β-unsaturated esters,nitriles and trisubstituted enones.Moreover,good to excellent regioselectivities are observed in the reaction of cinnamates with dicyanobenzene.Synthetic utility of this electrochemical approach is further demonstrated by direct late-stage functionali-zation of(S)-verbenone and 16-dehydropregnenolone acetate. 展开更多
关键词 UNSATURATED BENZENE electrochemical
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