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Chinese Chemical Letters 2014年第11期25卷 1461-1465页

作者： Feng Li chun-shan lu Xiao-Nian Li Institute of Industrial Catalysis of Zhejiang University of Technology State Key Laboratory Breeding Base of Green Chemistry Synthesis Technology

The effect of the amount of precipitant ammonia on the Cu0/Cu＋ratio of Cu/Si O2 prepared by the deposition–precipitation method is investigated. Species at different preparation stages, resulted from the amount of ammonia used, are identified by the XRD and FTIR techniques. Chrysocolla together with either copper nitrate hydroxide or copper hydroxide coexist in the uncalcined catalysts. Upon calcination, the latter two species are converted to Cu O particles while chrysocolla remains. Following reduction, Cu O is transformed to metallic Cu and chrysocolla is converted to Cu2 O. The value of Cu0/Cu＋ratio can be evaluated using the peak areas in their TPR profiles. Hydrogenation of dimethyl oxalate（DMO） to ethylene glycol（EG） shows that the selectivity of EG depends on the Cu0/Cu＋ratio. Catalyst prepared with the addition of ammonia solution at n（NH3）/n（Cu2＋） = 0.9 for precipitation–deposition gains a more suitable Cu0/Cu＋ratio upon reduction and thus has a higher selectivity for EG.

关键词： Amount of ammonia Deposition–precipitation Chrysocolla Copper nitrate hydroxide Copper hydroxide DMO hydrogenation

Improvement of the stability of Hg/AC catalysts by CsCl for the high-temperature hydrochlorination of acetylene

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Chinese Chemical Letters 2016年第6期27卷 822-826页

作者： Xiao-Long Xu Jia Zhao chun-shan lu Tong-Tong Zhang Xiao-Xia Di shan-Chuan Gu Xiao-Nian Li Institute of Industrial Catalysis of Zhejiang University of Technology State Key Laboratory Breeding Base of Green Chemistry Synthesis Technology

Activated carbon-supported mercuric chloride（HgCl2） is used as an industrial catalyst for acetylene hydrochlorination. However, the characteristic of easy sublimation of HgCl2 leads to the deactivation o the catalyst. Here, we showed that the thermal stability of the Hg/AC catalyst can be evidently improved when Cs Cl is added into the Hg/AC catalyst. Compared with the pure Hg/AC catalyst, the sublimation rate of HgCl2 from the Hg–Cs/AC catalyst decreased significantly and the Hg–Cs/AC catalyst showed bette catalytic activity and stability in the reaction. This promoting effect is related to the existence of cesium mercuric chlorides（CsxHgyCl（x＋2y）） highlighted by XRD, HR-TEM and EDX analyses. Thus, reacting HgCl2 with alkali chlorides to form alkali-mercuric chlorides may be a key to design highly efficient and thermally stable mercuric chloride catalyst for hydrochlorination reactions.

关键词： Cesium chloride Mercuric chloride Sublimation Hydrochlorination of acetylene Cesium–mercuric chlorides

Behavior of adsorbed diphenyl-sulfide on the Pd/C catalyst for o-chloronitrobenzene hydrogenation

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Chinese Chemical Letters 2013年第1期24卷 59-62页

作者： Chang Su Xiao-Nian Li Qun-Feng Zhang Lei Ma chun-shan lu Feng Feng Industrial Catalysis Institute of Zhejiang University of Technology

A series of diphenyl-sulfide （Ph2S）-immobilized Pd/C catalysts （Pd-Ph2Scx）/C） were prepared using the wetness-impregnation and immobilization method. Pd-Ph2S（x）/C catalysts employed for the hydro- genation of o-chloronitrobenzene showed very high selectivity. The structure of Pd-Ph2Scx）/C with different molar ratio of ligand （x-values） was characterized by XPS and TG-DSC-MS. The results suggest a ＂saturated＂ surface ratio of Ph2S/Pd （about 0.3） was formed on the Pd-Ph2S（x）[C catalysts surface. The Ph2S immobilized on the Pd particle is quite stable, and the desorption of Ph2S or dissociative loss of phenyl group was only found at temperatures above 500 K. The possible catalytic mechanism of the Pd-Ph2S（x）/C catalyst was also discussed.

关键词： Pd-Ph2S(x)/C o-Chloronitrobenzene Hydrogenation

Highly selective hydrogenation of halonitroaromatics to aromatic haloamines by ligand modified Ni-based catalysts

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Chinese Chemical Letters 2012年第5期23卷 545-548页

作者： chun shan lu Jing Hui Lv Lei Ma Qun Feng Zhang Feng Feng Xiao Nian Li Industrial Catalysis Institute of Zhejiang University of Technology State Key Laboratory Breeding Base of Green Chemistry Synthesis TechnologyZhejiang University of TechnologyHangzhou 310032China

Ligand modification of Ni-based catalysts by coordination of dicyandiamide to Ni metal leads to enhanced selectivity for the selective hydrogenation of *** selectivity of above 99.9%to aromatic haloamines can be achieved at the conversion of 100%.The results of H_2-TPD and FT-IR experiments show that Ni^-H~＋ species possessing the properties of Lewis acid site on the surface of Raney Ni could be responsible for the *** Raney Ni was treated by dicyandiamide,Ni^-H~＋ species interacted with N atom from the *** interaction was stable even at reaction temperature,which reduced the possibility to form the intermediate state of Ar-Cl...H~＋Ni^-.And then C-Cl bond could not be polarized and *** hvdrodechlorination process was suppressed effectively.

关键词： Halonitroaromatics Hydrogenation Ni catalyst Hydrodehalogenation

Selective hydrogenation of dimethyl maleate to tetrahydrofuran over Cu/SiO_2 catalyst:Effect of Cu^+ on the catalytic performance

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Chinese Chemical Letters 2015年第9期26卷 1150-1154页

作者： Xue-Qing Han Qun-Feng Zhang Feng Feng chun-shan lu Lei Ma Xiao-Nian Li Institute of Industrial Catalysis ofZhejiang University of Technology State Key Laboratory Breeding Base of Green Chemistry Synthesis Technology

Cu/SiO2 catalysts prepared by different methods have been investigated focusing on the influence of Cu^＋on the catalytic *** composition,structure and copper valence state were characterized by means of BET,XRD,XPS,FTIR,*** was found that the Cu/SiO2 prepared by ammoniaevaporation（AE） method had much higher TOF value than that prepared by wetness-impregnation（WI）with the same THF *** higher TOF value was attributed to the coexistence of Cu^＋ and Cu^0species in the activated AE-Cu/*** only Cu° species existing in the activated Wl-Cu/*** suggest that Cu^＋ can adsorb and polarize the C=0 bond of *** is concluded that Cu°could be the main active site and the synergistic effect between Cu^0 and Cu^＋ could contribute to hydrogenation of DMM to THF.

关键词： Dimethyl maleate Tetrahydrofuran Copper phyllosilicate Silica-supported copper Copper valence state

Preparation,structural characterization of a novel egg-shell palladium sulfide catalyst and its application in selective reductive alkylation reaction

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Chinese Chemical Letters 2012年第10期23卷 1111-1114页

作者： Qun Feng Zhang Jia chun Wu Chang Su Feng Feng Qiao Ling Ding Zhao Lian Yuan Hong Wang Lei Ma chun shan lu Xiao Nian Li Industrial Catalysis Institute State Key Laboratory Breeding Base of Green Chemistry Synthesis TechnologyZhejiang University of TechnologyHangzhou 310032China

A novel egg-shell Pd-S catalyst with palladium metal as the core and a membrane of palladium sulfide as the surface has been prepared by sulphidizing Pd/C with H2S. This catalyst is effective for the reductive alkylation of p-amino diphenylamine （PADPA） and methylisobutyl ketone （MIBK） to afford N-（1,3-dimethylbutyl）-N^-phenyl-p-phenylenedianine （DBPPD） with conversion up to 99.42% and selectivity to 97.46%. Comparing with the other common palladium sulfide catalysts, the membrane of palladium sulfide on the surface and the core of palladium metal cause the Pd on the surface of the new catalyst in a lower sulfur coordination, which improves its activity. Our result indicates that this new egg-shell Pd-S/C is an efficient hydrogenation catalyst.

关键词： HaS Palladium sulfide Egg-shell Reductive alkylation

Comparison of His-purkinje bundle pacing and right ventricular inflow tract septal pacing in the elderly

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Journal of Geriatric Cardiology 2020年第6期17卷 351-358页

作者： chun-shan lu Wen-Long DAI Dong-Ping FANG Peng HAO Dong-Fang HE Qiao-Yuan LI Xu LIU Can-Can LIN Cheng-Jun GUO Department of Cardiology Beijing Anzhen HospitalCapital Medical UniversityBeijing Institute of HeartLung and Blood Vessel DiseasesBeijingChina

Objective To compare the short-term clinical effect and electrical parameters of His-purkinje bundle pacing(HPBP) and right ventricular inflow tract septal pacing(RVIP) in the elderly. Methods Between April 2017 and September 2019, sixty patients with indications for permanent cardiac pacing and resynchronization therapy in Beijing Anzhen Hospital were divided into the HPBP and RVIP groups, and were analyzed. A ventricular pacing lead was implanted in left ventricular septal sites with left bundle potentials or His potentials in the HPBP group. The lead was placed in right ventricular inflow tract septal sites close to distal His-bundle regions without potentials from the His-purkinje conduction system in the RVIP group. Lead impedance, R wave amplitude, pacing thresholds, QRS duration, left ventricular ejection fraction(LVEF), and left ventricular end-diastolic diameter(LVEDD), mitral regurgitation area reflux, QTc, T wave directivity, Tp-e and Tp-e/QT ratio were compared between the HPBP and RVIP groups during the procedure and the short-month follow-up. Results No significant differences were found in lead impedance, R wave amplitude, QRS duration, LVEF, LVEDD, mitral regurgitation area reflux, QTc, T wave directivity, Tp-e and Tp-e/QT ratio between the HPBP and RVIP groups. However, the pacing threshold was significantly lower in the HPBP group than in the RVIP group(0.7 ± 0.2 vs. 0.9 ± 0.3 V, P = 0.02). Conclusions The efficacy and electrical parameters of HPBP is comparable with RVIP during the procedure and the short-term follow-up.

关键词： Bundle branch block His-purkinje bundle pacing Pacemaker Right ventricular inflow tract

The promoting role of minor amount of water in solvent-free hydrogenation of halogenated nitrobenzenes

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Chinese Chemical Letters 2014年第2期25卷 205-208页

作者： Jing-Hui Lyu Xiao-Bo He chun-shan lu Lei Ma Qun-Feng Zhang Feng Feng Xiao-Nian Li Jian-Guo Wang Institute of Industrial Catalysis College of Chemical Engineering and Materials ScienceZhejiang University of Technology

This study shows that minor amount of water plays a very important role in solvent-free hydrogenation of halogenated nitrobenzenes. For dried sponge Pd, the reaction cannot occur in the absence of water. For Pd/C catalyst, minor amount of water reduces the induction time, increases the reaction rate and reaction TOFs. Water might enhance the diffusion, adsorption and dissociation of H2 on Pd catalysts.

关键词： Halogenated nitrobenzenes Solvent Free Water Hydrogenation

Initial experience with ablation of the innervation surrounding sinus and atrioventricular nodes to treat paroxysmal bradyarrhythmia

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Chinese Medical Journal 2020年第2期133卷 134-140页

作者： chun-shan lu Cheng-Jun Guo Dong-Ping Fang Peng Hao Dong-Fang He Ai-Guo Xu Division of Cardiology Department of MedicineBeijing Anzhen HospitalCapital Medical UniversityBeijing Institute of HeartLung and Blood Vessel DiseasesBeijing 100029China

Background:The symptomatic bradyarrhythmia is Class I indication for pacing therapy which is not a radical *** present study aimed to assess the feasibility and to present the initial results of the restricted ablation of the parasympathetic innervation surrounding sinus and atrioventricular(AV)nodes for treating patients with ***:A total of 13 patients with cardiogenic syncope were included from May 2008 to June *** the guidance of fluoroscopy and/or three-dimensional geometry by 64-slice spiral computed tomography,atrial activation sequence in sinus rhythm was *** geometry was reconstructed manually or automatically using the Niobe II magnetic navigation system integrated with the CARTO-remote magnetic technology(RMT)*** was targeted at the high-amplitude fractionated electrograms surrounding the regions of His bundle and the site with the earliest activation in sinus *** surrounding the sinus node,AV node,and the phrenic nerve were ***:Thirteen patients completed the *** was successfully performed in 12 patients and failed in *** highfrequency potential was recorded in atrial electrograms surrounding the sinus or AV nodes in all the patients and disappeared in 15 s after radiofrequency *** vagal reaction was observed before the improvement of the sinus and AV node *** complications occurred during the *** were followed up for a mean of 13.0±5.9 *** the follow up ten patients remained free of symptoms,and two patients had a permanent cardiac pacemaker implanted due to spontaneous recurrence of *** heart rate of post-ablation was higher than pre-ablation(69.0±11.0 vs.49.0±10.0 beats/min,t=4.56,P=0.008).The sinus node recovery time,Wenckebach block point,and atrium-His bundle interval were significantly shorter after ablation(1386.0±165.0 vs.921.0±64.0 ms,t=7.45,P=0.002;590.0±96.0 vs.464.0±39.0 ms,t=2.38,P=0.0

关键词： Electrophysiology Radiofrequency ablation Sinus node dysfunction Atrioventricular block Syncope

The Citron homology domain of MAP4Ks improves outcomes of traumatic brain injury

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Neural Regeneration Research 2025年第11期20卷 3233-3244页

作者： Xiaoling Zhong Wenjiao Tai Meng-lu Liu Shuaipeng Ma Tianjin Shen Yuhua Zou chun-Li Zhang Department of Molecular Biology University of Texas Southwestern Medical CenterDallasTXUSA Hamon Center for Regenerative Science and Medicine University of Texas Southwestern Medical CenterDallasTXUSA Peter O’Donnell Jr.Brain Institute University of Texas Southwestern Medical CenterDallasTXUSA

The mitogen-activated protein kinase kinase kinase kinases(MAP4Ks)signaling pathway plays a pivotal role in axonal regrowth and neuronal degeneration following *** targeting this pathway is beneficial to brain injury remains *** this study,we showed that adeno-associated virus-delivery of the Citron homology domain of MAP4Ks effectively reduces traumatic brain injury-induced reactive gliosis,tauopathy,lesion size,and behavioral *** inhibition of MAP4Ks replicated the ameliorative effects observed with expression of the Citron homology ***,the Citron homology domain acted as a dominant-negative mutant,impeding MAP4K-mediated phosphorylation of the dishevelled proteins and thereby controlling the Wnt/β-catenin *** findings implicate a therapeutic potential of targeting MAP4Ks to alleviate the detrimental effects of traumatic brain injury.

关键词： adeno-associated virus Citron homology Citron homology domain gene therapy mitogen-activated protein kinase kinase kinase kinases traumatic brain injury