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Synthesis of Silica-Dispersed NiMo Hydrodesulfurization Catalysts

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China Petroleum Processing & Petrochemical Technology 2010年第4期12卷 18-22页

作者： Liu Di Liu Lihua Li Guangci Liu Chenguang (State key Laboratory of Heavy Oil Processing,CNPC key Laboratory of Catalysis, China University of Petroleum,Qingdao 266555) State key Laboratory of Heavy Oil Processing CNPC Key Laboratory of Catalysis China University of Petroleum Qingdao 266555 China

分散硅石的 NiMo hydrodesulfurization 催化剂被免职降水方法综合。为比较目的，体积 NiMo 催化剂被一起沉淀获得。分散硅石的 NiMo 催化剂有高度活跃的金属内容。硅石被采用为活跃部件的完整的利用驱散活跃金属。赌注分析证明分散硅石... 详细信息

分散硅石的 NiMo hydrodesulfurization 催化剂被免职降水方法综合。为比较目的，体积 NiMo 催化剂被一起沉淀获得。分散硅石的 NiMo 催化剂有高度活跃的金属内容。硅石被采用为活跃部件的完整的利用驱散活跃金属。赌注分析证明分散硅石的 NiMo 催化剂有一个高表面区域(147.0 m2/g ) 和毛孔体积(0.27 mL/g ) ，而体积 NiMo 催化剂展出了一个很低的表面区域(87.5 m2/g ) 。传播电子显微镜学结果证明活跃部件在 SiO2 底层上被驱散。分散硅石的 NiMo 催化剂和体积 NiMo 催化剂的 X 光检查衍射模式被索引到 NiMoO4。分散硅石的 NiMo 催化剂的 hydrodesulfurization 活动比引用催化剂的高得多并且能直到比那些两次大商业 NiMo 支持氧化铝的系统每催化剂的克。测试结果的活动也证明分散硅石的 NiMo 催化剂是有效 hydrodesulfurization 催化剂。

关键词：加氢脱硫催化剂二氧化硅分散合成透射电子显微镜比表面积沉积沉淀法加氢催化剂

Influence of Substrate Conformation on the Deglycosylation of Ribonuclease B by Recombinant Yeast Peptide:N-glycanase

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Acta Biochimica et Biophysica Sinica 2007年第1期39卷 8-14页

作者： Shengjun WANG Peng George WANG and Qingsheng QI State key Laboratory of Microbial Technology,Life Science Schooll,Shandong University,Jinan 250100,China State key Laboratory of Microbial Technology Life Science School Shandong UniversityJinan 250100 China

Peptide:N-glycanase has been thought to be responsible for proteasome-dependent degradationof misfolded glycoproteins translocated from the endoplasmic reticulum (ER) to the cytosol.Therefore,theenzyme was supposed to be able to distinguish between native and non-native glycoproteins.In the presentstudy,a recombinant,yeast peptide:N-glycanase,Png lp, was expressed in Escherichia coli as inclusionbodies and was purified,refolded and characterized.The results showed that the recombinant enzymehas a broad pH range adaptation,from pH 4.0 to pH 10.0,and has an optimum temperature of 30 ℃.This enzyme is a zinc metalloenzyme.Its activity was abolished with the addition of EDTA and notrestored by adding metal ions.Furthermore,the deglycosylation efficiency of recombinant Pnglpfrom E.coli was investigated with respect to the substrate conformation in vitro.When ribonuclease B(RNase B) was denatured at 60-65 ℃ or by 40-60 mM dithiothreitol, indicated by its obvious structuralchange and sharpest activity change,its deglycosylation by Pnglp was most prominent.The deglycosylationefficiency of RNase B by Pnglp was found to be related to its structural conformation and enzymaticactivity.

关键词： glycanase ribonuclease B glycoprotein deglycosylation circular dichroism

Direct Electrodeposition of Cu-Ni-W Alloys for the Liners for Shaped Charges

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Journal of Materials Science & Technology 2010年第5期26卷 429-432页

作者： Hanwei He and Shouya Jia State key Lab of Powder Metallurgy,Central South University,Changsha 410083,China State key Lab of Powder Metallurgy Central South University Changsha 410083 China

The Cu-Ni-W alloys for the liners for shaped charges were successfully prepared by direct current（DC） electrodeposition.The influence of cathode current density on morphology,microstructure and composition of the Cu-Ni-W alloys was investigated by means of scanning electron microscopy（SEM）,X-ray diffraction（XRD） and energy dispersive spectrometry（EDS）.With the increasing of current density,the copper content reduces gradually and the nickel and tungsten content increase; the crystallite size is decreased.When the current density is 15 A/dm 2 the tungsten content reaches 12.96 wt pct,and the crystallite size is submicron degree.The Cu-Ni-W alloy is face-centered cubic（fcc） solid solution.All of the Cu-Ni-W alloys take on（220） texture.

关键词： Electrodeposition Cu-Ni-W alloy Cathode current density

Analysis micro-mechanism of burrs formation in the case of nanometric cutting process using numerical simulation method

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Science China(Technological Sciences) 2007年第2期50卷 129-137页

作者： HAN XueSong & HU YuanZhong State key Laboratory of Tribology, Tsinghua University, Beijing 100084, China State key Laboratory of Tribology Tsinghua University Beijing China

Burrs (exit failure), being one of the important factors influencing the final precision of workpiece, have been widely studied. Today, with the development of manufac- turing technology, the depth of cut falls into the range of nanometer or sub- nanometer, there may be some different disciplines dominating the burrs genera- tion process. Molecular dynamics (MD) method, which is different from continuous mechanics, plays an important role in describing microscopic world. Take the ex- ample of single crystal copper, this paper carries out MD analysis micro-mecha- nism of burrs generation process. The results show that the burrs geometry de- pends on the type of workpiece (ductile or brittle). The depth of cut is decreased in the case of positive burrs generation process while the depth of cut is increased in case of negative burrs generation process.

关键词： burr molecular dynamics micro-mechanism

A NEW ALGORITHM FOR ELIMINATING PHASE-SHIFT ERROR IN PHASE SHIFTING INTERFEROMETRY

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Chinese Journal of Mechanical Engineering 1999年第2期12卷 51-55页

作者： Liu Chong Liang Xichang Peng Donglin State key Laboratory of Mechanical Transmission,Chongqing University Chongqing Univ China

The effect of phaseshift error in phase shifting interferometry is investigated. A new algorithm with two sets of 4 samples for eliminating phase shift error is presented. The computer simulation and experiment result show that the phase shift offset should be π when the algorithm is used, and this algorithm has gotten better result than the original 4 sample algorithm.

关键词： Phase shifting interferometry Error compensation Profile measurement

Ammonium improves iron nutrition by decreasing leaf apoplastic pH of sunflower plants(Helianthus annuus L.cv.Frankasol)

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Chinese Science Bulletin 2003年第20期48卷 2215-2220页

作者： ZOU Chunqin & ZHANG Fusuo key Laboratory of Plant-Soil Interactions, Ministry of Education key Laboratory of Plant Nutrition, Ministry of Agriculture of China Department of Plant Nutrition, China Agricultural University, Beijing 100094, China Correspondence should be addressed to Zhang Fusuo (e-mail: zhangfs@ ***) Minist Educ Key Lab Plant Soil Interact Beijing 100094 Peoples R China Minist Agr Key Lab Plant Nutr Beijing 100094 Peoples R China China Agr Univ China Dept Plant Nutr Beijing 100094 Peoples R China

The effect of nitrogen form on pH and concentration of soluble iron (Fe) in leaf apoplast was investigated in hydrophonically grown sunflower plants (Helianthus annuus L. cv. Frankasol), and the mechanism underlying the improved Fe nutrition by ammonium (NH4) supply was also elucidated. Ammonium supply ameliorated Fe nutrition of plants grown without Fe through decreasing apoplastic pH and increasing soluble Fe concentration in apoplastic fluid of young leaves. The soluble Fe concentration in apoplastic fluid and cell sap of young leaves, and xylem exudates of NH4 fed-plants was higher than that of nitrate (NO3) fed-plants, and no typical Fe-deficiency chlorosis in young leaves was observed in NH4 fed plant without Fe supply. The apoplastic pH was 6.15 and 5.94 in young leaves of Fe-deficient plants fed respectively with NO3 and NH4, while in Fe-sufficient plants, the apoplastic pH was 6.43 with NO3, and 5.50 with NH4 supply. In primary leaves, the apoplastic pH was around 6.25 irrespective of nitrogen form and Fe supply. The pH of xylem exudate was 5.72 in Fe-deficient plants fed with NO3 and 5.49 with NH4. Iron nutrition increased the pH of xylem exudate by 0.27 and 0.16 unit under NO3 and NH4 supply respectively.

关键词：向日葵铁营养学非原质体 pH值氮铵赋存形态植物生理学

Effects of sintering pressure and temperature on microstructure and tribological characteristic of Cu-based aircraft brake material

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中国有色金属学会会刊：英文版 2007年第4期17卷 669-675页

作者：熊翔盛洪超陈洁姚萍屏State key Laboratory of Powder Metallurgy Central South University State key Laboratory of Powder Metallurgy Central South University

A novel Cu-based P/M aircraft brake material was prepared and the effects of sintering pressure and temperature on microstructure and tribological characteristic were investigated. For the constant sintering temperature, when the sintering pressure increases from 0.5 MPa to 1.5 MPa, the porosity, wear loss and friction coefficient decrease remarkably. When the sintering pressure increases from 1.5 MPa to 2.5 MPa, the porosity further decreases but in a little degree and wear behaviors are improved slightly. However, once the sintering pressure is larger than 2.5 MPa, it has no obvious effect on microstructure and tribological characteristic. For the constant sintering pressure, when the sintering temperature increases from 900 ℃ to 930 ℃, the sintered density remarkably increases, and wear behaviors are obviously improved. For further increasing sintering temperature to 1 000 ℃, the density keeps on increasing, but wear behaviors change slightly.

关键词：摩擦材料烧结压力烧结温度飞机制动材料铜基材料微观结构

Enhanced anaerobic biodegradability of real coal gasification wastewater with methanol addition

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Journal of Environmental Sciences 2010年第12期22卷 1868-1874页

作者： Wei Wang,Hongjun Han,Min Yuan,Huiqiang Li State key Laboratory of Urban Water Resource and Environment,Harbin Institute of Technology,Harbin 150090,China State key Laboratory of Urban Water Resource and Environment Harbin Institute of Technology Harbin 150090 China

Coal gasification effluent is a typical refractory industrial wastewater with a very poor anaerobic biodegradability due to its toxicity. Methanol was introduced to improve anaerobic biodegradability of real coal gasification wastewater, and the effect of methanol addition on the performance was investigated in a mesophilic upflow anaerobic sludge bed reactor with a hydraulic retention time of 24 hr. Experimental results indicated that anaerobic treatment of coal gasification wastewater was feasible with the addition of methanol. The corresponding maximum COD and phenol removal rates were 71% and 75%, respectively, with methanol concentration of 500 mg COD/L for a total organic loading rate of 3.5 kg COD/（m^3.day） and a phenol loading rate of 0.6 kg/（m^3.day）. The phenol removal rate was not improved with a higher methanol concentration of 1000 mg COD/L. Substrate utilization rate （SUR） tests indicated that the SURs of phenol were 106, 132, and 83 mg phenol/（g VSS.day） at methanol concentrations of 250, 500, and 1000 mg COD/L, respectively, and only 45 mg phenol/（g VSS.day） in the control reactor. The presence of methanol could reduce the toxicity of coal gasification wastewater and increase the biodegradation of phenolic compounds.

关键词： coal gasification wastewater anaerobic biodegradability phenol methanol

Interannual variation of annual precipitation and urban effect on precipitation in the Beijing region

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Progress in Natural Science:Materials International 2007年第9期17卷 1042-1050页

作者： Yu Shuqiu(State key Laboratory on Severe Weather,Chinese Academy of Meteorological Sciences,Beijing 100081,China) State key Laboratory on Severe Weather Chinese Academy of Meteorological Sciences Beijing 100081 China

The large scale character of the interannual variation of precipitation and the urban effect on local annual precipitation anomaly are investigated in this paper based on the 1960-2000 annual precipitation observations at 20 stations in the Beijing region.The results show that:the annual precipitation in the Beijing region possesses the large scale variation character with the linear trend of-1.197/10 yr,which corresponds to a total reduction of 27.82 mm in annual precipitation in the 41 years;the local annual precipitation anomalies(percent of the normal 1960-2000)show a positive center near the urban area,i.***.urban precipitation island(UPI),whose intensity increases with the linear trend of 0.6621%/10 yr,opposite to the interannual trend of large scale precipitation over the Beijing region;changes in the UPI are also associated with the intensity of synoptic processes of precipitation,and when the synoptic processes are strong(wet years),the intensity of UPI strengthens,while the synoptic processes are weak(dry years),and the UPI disappears in the Beijing region.

关键词： urban precipitation island effect interannual climate variation precipitation Beijing atmospheric science