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Characteristic atom occupation patterns of Au_3Cu,AuCu_3,AuCuI and AuCuII based on experimental data of disordered alloys 被引量:3
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作者 谢佑卿 李艳芬 +3 位作者 刘心笔 李晓波 彭红建 聂耀庄 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第5期1092-1104,共13页
The potential energies, volumes and electronic structures of characteristic atoms coordinated by neighboring configurations were obtained from the experimental heats of formation and lattice parameters of disordered A... The potential energies, volumes and electronic structures of characteristic atoms coordinated by neighboring configurations were obtained from the experimental heats of formation and lattice parameters of disordered Au1-xCux alloys. From characteristic atom occupation (CAO) patterns of L12-Au3Cu, L12-AuCu3 and Llo-AuCu compounds, their electronic structures, volumetric and energetic properties were calculated. The CAO pattern of Johasson-Linde(J-L) model shows that the transition AuCuI→AuCulI is an exothermic and volume contraction reaction, which is opposite from experimental phenomena. According to CAO pattern of Guymont-Feutelais-Legendre(G-F-L) model, the AuCulI cell consists of two periodic antidirection (PAD) AuCuI regions and two PAD boundary regions. The equations derived from CAO pattern of G-F-L model can be used to calculate energetic properties, volumetric properties and ordering degrees of the PAD AuCuI region and PAD boundary region, as well as corresponding average properties of the AuCulI phase. The results are consistent with experimental phenomena. 展开更多
关键词 Au-Cu system INTERMETALLICS electronic structure crystalline structure characteristic atom occupation pattern
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Isolation and Biological Characteristics of Bacteriophage of an Antibiotic-resistant Escherchia coli Strain 被引量:1
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作者 李淑芳 邓瑞玲 +3 位作者 张帅领 张智慧 梁垲珊 张继东 《Agricultural Science & Technology》 CAS 2016年第12期2692-2695,2706,共5页
In this study, bacteriophage of an antibiotic-resistant Escherchia coil strain isolated from feces of chicken was isolated. Its host range was determined by the method of spotting sample on monolayer agar, and its lys... In this study, bacteriophage of an antibiotic-resistant Escherchia coil strain isolated from feces of chicken was isolated. Its host range was determined by the method of spotting sample on monolayer agar, and its lysis titer, optimal multiplicity of infection (MOI), temperature tolerance and pH tolerance were determined by the double-layer agar plate method. The results showed that the bacteriophage had a broad host range. The biological assay demonstrated that two strains of E. coil were fully lysed and one strain of E. coil was weakly lysed by the bacteriophage. The lysis titer and MOI of the bacteriophage were 1.20×10^8 PFU/ml and 1, respec- tively. Under the optimum temperature of 40℃, the Jysis titer of the bacteriophage reached 8.90×10^9 PFU/ml; however, the bacteriophage lost its infectivity at the tem- perature of 80℃. In the pH range of 5-11, the lysis titer of the bacteriophage ranged from10^6 to 10^9 PFU/mI. Under the condition of pH 4 and 12, the bacterio- phage was invalid. 展开更多
关键词 BACTERIOPHAGE Escherchia coli Antibiotic resistance Biological charac-teristics
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Metafunctions and stylistic features of nominalization
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作者 丛迎旭 《Sino-US English Teaching》 2007年第5期54-58,共5页
As an important feature of written language, nominalization is frequently used in formal texts. Using the approach of systemic functional grammar, the paper presents a detailed analysis of the three metafunctions of n... As an important feature of written language, nominalization is frequently used in formal texts. Using the approach of systemic functional grammar, the paper presents a detailed analysis of the three metafunctions of nominalization, which entails the positive and negative stylistic effects. The paper also discusses the relationship between form, function and stylistic features. 展开更多
关键词 NOMINALIZATION meta-functions grammatical metaphor stylistic features
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Effect of ligand of peroxisome proliferator-activated receptor γ on the biological characters of hepatic stellate cells 被引量:5
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作者 Yan-Tong Guo Xi-Sheng Leng Tao Li Ji-Run Peng Sheng-Han Song Liang-Fa Xiong Zhi-Zhong Qin 《World Journal of Gastroenterology》 SCIE CAS CSCD 2005年第30期4735-4739,共5页
AIM: To study the effect of rosiglitazone, which is a ligand of peroxisome proliferator-activated receptor gamma (PPARy), on the expression of PPARy in hepatic stellate cells (HSCs) and on the biological characte... AIM: To study the effect of rosiglitazone, which is a ligand of peroxisome proliferator-activated receptor gamma (PPARy), on the expression of PPARy in hepatic stellate cells (HSCs) and on the biological characteristics of HSCs. METHODS: The activated HSCs were divided into three groups: control group, 3 μmol/L rosiglitazone group, and 10 μmol/L rosiglitazone group. The expression of PPARγ, α-smooth muscle actin (α-SMA), and type Ⅰ and Ⅲ collagen was detected by RT-PCR, Western blot and immunocytochemical staining, respectively. Cell proliferation was determined with methylthiazolyltetrazolium (MTT) colodmetric assay. Cell apoptosis was demonstrated with flow cytometry. RESULTS: The expression of PPARγ at mRNA and protein level markedly increased in HSCs of 10 μmol/L rosiglitazone group (tvalue was 10.870 and 4.627 respectively, P〈0.01 in both). The proliferation of HSCs in 10 μmol/L rosiglitazone group decreased significantly (t = 5.542, P〈0.01), α-SMA expression level and type Ⅰ collagen synthesis ability were also reduced VS controls (tvalue = 10.256 and 14.627 respectively, P〈0.01 in both). The apoptotic rate of HSCs significantly increased in 10 μmol/L rosiglitazone group vs control (X^2= 16.682, P〈0.01). CONCLUSION: By increasing expression of PPARγ in activated HSCs, rosiglitazone, an agonist of PPARγ, decreases α-SNA expression and type Ⅰ collagen synthesis, inhibits cell proliferation, and induces cell apoptosis. 展开更多
关键词 Peroxisome proliferator-activated receptor gamma Hepatic stellate cell ROSIGLITAZONE
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Biological characters and rDNA ITS sequences of pathogen of poplar leaf blight 被引量:4
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作者 JI Hong-fang YANG Qian SONG Rui-qing 《Journal of Forestry Research》 SCIE CAS CSCD 2006年第1期17-20,共4页
DNA was extracted from the strain of pathogen of poplar leaf blight using a modified CTAB method. ITS sequence (601bp) was initially amplified from the pathogen by using the universal primers ITSl and ITS4 (registe... DNA was extracted from the strain of pathogen of poplar leaf blight using a modified CTAB method. ITS sequence (601bp) was initially amplified from the pathogen by using the universal primers ITSl and ITS4 (registered No, DQ011257). Comparing to the nucleotide sequences acquired from GenBank database, the strain is clustered into the homogeneity with Alternaria alternate (AY787684) and Alternaria alternate (AY354228), with a homology of 98%, thus the strain was checked as Alternaria alternata (Fr.) Keissler. The optimal conditions for conidia germination and mycelium growth of the pathogen were tested, The optimal temperature for conidia germinating and mycelium growth is 25℃, and the optimal pH value is 6. Mycelium grows rather slowly at 10℃ and 30℃ and growth stops at above 35 ℃. Among the six culture mediums tested, PDA + poplar leaf juice medium is most favorable for mycelium growth. 展开更多
关键词 PATHOGEN Popular leaf blight Alternaria alternate rDNA ITS sequences Biological characteristics
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MINERALOGICAL FEATURES OF ULTRAMAFIC HYPOXENOLITHS IN ALKALI-RICH PORPHYRY 被引量:2
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作者 LIU Xianfan YANG Zhengxi +3 位作者 LIU Jiaduo ZHANG Chengjiang WU Dechao LI Youguo 《Geotectonica et Metallogenia》 2003年第1期81-90,共10页
Ultramafic hypoxenoliths found in the alkali-rich porphyry in the Liuhe Village, Heqing, Yunnan, China, are of great significance in understanding the origin and evolution of the porphyry. This paper discusses the min... Ultramafic hypoxenoliths found in the alkali-rich porphyry in the Liuhe Village, Heqing, Yunnan, China, are of great significance in understanding the origin and evolution of the porphyry. This paper discusses the mineralogical features of the hypoxenoliths. It shows that the xenoliths are characterized by the upper mantle rocks modified to certain extent by the enriched mantle fluid metasomatism in the mantle environment, with the enriched mantle property of low-degree partial melting. This constitutes the important mineralogical evidence for the petrogenesis and mineralization of alkali-rich porphyry. 展开更多
关键词 alkali-rich porphyry deep-source xenoliths enriched mantle low-degree partial melting mineralogical characteristics
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Structural insights into a dual-specificity histone demethylase ceKDM7A from Caenorhabditis elegans 被引量:3
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作者 Ying Yang Lulu Hu +14 位作者 Ping Wang Haifeng Hou Yan Lin Yi Liu Ze Li Rui Gong Xiang Feng Lu Zhou Wen Zhang Yuhui Dong Huirong Yang Hanqing Lin Yiqin Wang Charlie Degui Chen Yanhui Xu 《Cell Research》 SCIE CAS CSCD 2010年第8期886-898,共13页
Histone lysine methylation can be removed by JmjC domain-containing proteins in a sequence- and methylationstate-specific manner. However, how substrate specificity is determined and how the enzymes are regulated were... Histone lysine methylation can be removed by JmjC domain-containing proteins in a sequence- and methylationstate-specific manner. However, how substrate specificity is determined and how the enzymes are regulated were largely unknown. We recently found that ceKDM7A, a PHD- and JmjC domain-containing protein, is a histone demethylase specific for H3K9me2 and H3K27me2, and the PHD finger binding to H3K4me3 guides the demethylation activity in vivo. To provide structural insight into the molecular mechanisms for the enzymatic activity and the function of the PHD finger, we solved six crystal structures of the enzyme in apo form and in complex with single or two peptides containing various combinations of H3K4me3, H3K9me2, and H3K27me2 modifications. The structures indicate that H3Kgme2 and H3K27me2 interact with ceKDMTA in a similar fashion, and that the peptide-binding specificity is determined by a network of specific interactions. The geometrical measurement of the structures also revealed that H3K4me3 associated with the PHD finger and H3K9me2 bound to the JmjC domain are from two separate molecules, suggesting a trans-histone peptide-binding mechanism. Thus, our systemic structural studies reveal not only the substrate recognition by the catalytic domain but also more importantly, the molecular mechanism of dual specifieity of ceDKM7A for both H3K9me2 and H3K27me2. 展开更多
关键词 HISTONE methylation DEMETHYLASE structure PHD JMJC
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Treatment for triple-negative breast cancer 被引量:2
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作者 Xuebing Shi Lu Wang 《The Chinese-German Journal of Clinical Oncology》 CAS 2012年第9期539-543,共5页
Triple-negative breast cancers (TNBCs) neither express estrogen receptor and progesterone receptor nor over- express human epidermal growth factor receptor-2. Because of the special molecular features, triple-negative... Triple-negative breast cancers (TNBCs) neither express estrogen receptor and progesterone receptor nor over- express human epidermal growth factor receptor-2. Because of the special molecular features, triple-negative breast cancer is not either sensitive to endocrine therapy or targeted therapy of trastuzumab. There has not been standard treatment regimen for triple-negative breast cancer yet and chemotherapy has still been the chief therapy currently. However, with the great progress of oncology and molecular biology, the understanding of the natural history, pathophysiology and molecular features of this disease has been greatly improved, and a growing number of novel and effective therapies and discoveries of new biological targets for this phenotype of breast cancers have been reported, which provide new insights into therapeutic strategies for the women suffering from it. 展开更多
关键词 tripPe-negative breast neoplasms THERAPY REVIEW
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Physical and Hydrodynamic Properties of Spherical Cellulose-Titanium Dioxide Composite Matrix for Expanded Bed Adsorption 被引量:5
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作者 雷引林 林东强 +2 位作者 姚善泾 刘坐镇 朱自强 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2003年第2期141-145,共5页
Expanded bed adsorption (EBA) has been widely used in industrial downstream bioprocessing. Solid matrix is the principal pillar supporting the successful application of EBA. A novel spherical cellulose-titanium dioxid... Expanded bed adsorption (EBA) has been widely used in industrial downstream bioprocessing. Solid matrix is the principal pillar supporting the successful application of EBA. A novel spherical cellulose-titanium dioxide composite matrix was prepared through the method of water-in-oil suspension thermal regeneration. Its typical physical properties were wet density 1.18g.cm-3, diameters in the range of 100-300um, porosity 85.5%, and water content 72.3%. Expansion characteristics and liquid mixing performance of the matrix in expanded bed were investigated using water and 10% (by mass) glycerol solution as mobile phases. The results indicate that the custom-assembled matrix has a stable flow hydrodynamics and exhibits the same degree of liquid-phase mixing or column efficiency as the commercially available Streamline adsorbent. 展开更多
关键词 expanded bed adsorption MATRIX CELLULOSE titanium dioxide
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Biological Characteristies of Methane Emission of Oryzasativa,Panicumcrus-galliand Cyperusdif for misGrown on PaddySoil 被引量:2
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作者 MINHANG CHENMEI-CI 《Pedosphere》 SCIE CAS CSCD 1994年第2期165-172,共8页
Biological characteristics of methane emission were compared among Oryza sativa, Panicum crus-galli andCyperus difformis grown on paddy soil. The order of the amounts of methane emitted was P. crus-galli > O. sativ... Biological characteristics of methane emission were compared among Oryza sativa, Panicum crus-galli andCyperus difformis grown on paddy soil. The order of the amounts of methane emitted was P. crus-galli > O. sativa >C. difformis, with the former two 11 and 8 times as much as that of the latter, respectively. And it was just opposite tothat of the methane-forming activities of roots of the three plants. The diurnal changes of methane emission of thethree plants were relatively consistent with valleys during 11:00-14:00 and midnight and peaks during 8:00-11: 00,14:00- 20:00 and about 5:00 early morning. The methanogenic activites in rhizospheric soils were higher than those innonrhizospheric soils with P. crus-galli and O. sativa, but not with C. difformis. The pathways of methane release ofP. crus-galli and O . sativa were probably through the top gaps near the junctions of nodal plate and leaf sheath, how-ever in C. difformistopgaps from which methane could escape into atmosphere were not found. 展开更多
关键词 activity of methane formation Cyperus difformis methane emission Oryza sativa Panicum crus-galli
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Effects of temperature and age on physico-mechanical properties of cemented gravel sand backfills 被引量:5
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作者 JIANG Fei-fei ZHOU Hui +2 位作者 SHENG Jia KOU Yong-yuan LI Xiang-dong 《Journal of Central South University》 SCIE EI CAS CSCD 2020年第10期2999-3012,共14页
Cemented backfill used in deep mines would inevitably be exposed to the ambient temperature of 20−60℃in the next few decades.In this paper,two types of cemented gravel sand backfills,cemented rod-mill sand backfill(C... Cemented backfill used in deep mines would inevitably be exposed to the ambient temperature of 20−60℃in the next few decades.In this paper,two types of cemented gravel sand backfills,cemented rod-mill sand backfill(CRB)and cemented gobi sand backfill(CGB),were prepared and cured at various temperatures(20,40,60℃)and ages(3,7,28 d),and the effects of temperature and age on the physico-mechanical properties of CRB and CGB were investigated based on laboratory tests.Results show that:1)the effects of temperature and age on the physico-mechanical properties of backfills mainly depend on the amount of hydration products and the refinement of cementation structures.The temperature has a more significant effect on thermal expansibility and ultrasonic performance at early ages.2)The facilitating effect of temperature and age on the compressive strength of CGB is higher than that on CRB.With the increase of temperature,the compressive failure modes changed from X-conjugate shear failure to tensile failure,and the integrity of specimens was significantly improved.3)Similarly,the shear performance of CGB is generally better than that of CRB.The temperature has a weaker effect on shear strength than age,but the shear deformation and shear plane morphology are closely related to temperature. 展开更多
关键词 cemented backfill gravel sand TEMPERATURE physico-mechanical properties deformation characteristics
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The Ejffect of Vertical Internal Baffles on Fluidization Hydrodynamics and Grain Drying Characteristics 被引量:3
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作者 LAWChungLim SitiMasrindaTASIRIN +1 位作者 WanRamliWanDAUD NGPinPin 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2004年第6期801-808,共8页
The effect of vertical internal baffles on the particle mixing and graindrying characteristics in a batch fluidized bed column is investigated. Experimental work wascarried out in a 3m high rectangular fluidized bed d... The effect of vertical internal baffles on the particle mixing and graindrying characteristics in a batch fluidized bed column is investigated. Experimental work wascarried out in a 3m high rectangular fluidized bed dryer of cross sectional area of 0.15 m x 0.61 mat different operating conditions using paddy, a group D particle, as the fluidizing material. Theresults of the study showed that the fluidized bed dryer system with vertical internal baffles gavebetter particle mixing effect in the bed of particles than that without vertical internal baffles.This is due to the fact that the vertical internal baffle act as gas bubble breakers by breaking upthe large gas bubbles into smaller ones. The smaller bubbles cause a more vigorous mixing in the bedof particles before finally erupting at the bed surface. This improves the contacting efficiencyand enhanced the heat and mass transfer of the fluidized bed system. Thus a higher drying rate wasobtained in the falling rate period because the higher contacting efficiency increases theevaporation rate at the particle surface. However, the drying rate in the diffusion region showslittle improvement because the moisture diffusivity does not depend on the contacting efficiency.The fluidized bed dryer with vertical internal baffles could therefore be used in the initial rapiddrying stage in a two stage drying strategy for paddy. The insertion of vertical internal bafflesinto a fluidized bed system improves the processing of Group D particles in a fluidized bed systemespecially if the system is large in scale. 展开更多
关键词 bubble characteristics critical moisture content drying curves fluidization quality fluidized bed dryer group d particles PADDY
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KN-93,a specific inhibitor of CaMKⅡ inhibits human hepatic stellate cell proliferation in vitro 被引量:3
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作者 Ping An Jun-Yong Zhu +4 位作者 Yan Yang Peng Lv Yi-Hao Tian Ming-Kai Chen He-Sheng Luo 《World Journal of Gastroenterology》 SCIE CAS CSCD 2007年第9期1445-1448,共4页
AIM: To investigate the effects of KN-93, a CaMKⅡ selective inhibitor on cell proliferation and the expression of p53 or p21 protein in human hepatic stellate cells. METHODS: Human hepatic stellate cells (LX-2) w... AIM: To investigate the effects of KN-93, a CaMKⅡ selective inhibitor on cell proliferation and the expression of p53 or p21 protein in human hepatic stellate cells. METHODS: Human hepatic stellate cells (LX-2) were incubated with various concentrations (0-50 μmol/L) of KN-93 or its inactive derivative, KN-92. Cell proliferation was measured by CCK-8 assay, and the expression of two cell cycle regulators, p53 and p21, was determined by SDS-PAGE and Western blotting. RESULTS: KN-93 (5-50 μmol/L) decreased the proliferation of human hepatic stellate cells in a dosedependent manner from 81.76% (81.76% ± 2.58% vs 96.63% ± 2.69%, P 〈 0.05) to 27.15% (27.15% ± 2.86% vs 96.59% ± 2.44%, P 〈 0.01) after 24 h treatment. Incubation of 10 μmol/L KN-93 induced the cell growth reduction in a time-dependent manner from 78.27% at 8 h to 11.48% at 48 h. However, KN-92, an inactive derivative of KN-93, did not inhibit cell proliferation effectively. Moreover, analysis of cell cycle regulator expression revealed that KN-93 rather than KN-92 reduced the expression of p53 and p21. CONCLUSION: KN-93 has potent inhibitory effect on proliferation of LX-2 cells by modulating the expression of two special cell cycle regulators, p53 and p21. 展开更多
关键词 KN-93 Human hepatic stellate cells LX-2 Cell proliferation
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Effects of water depth and substrate color on the growth and body color of the red sea cucumber,Apostichopus japonicus 被引量:3
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作者 姜森颢 董双林 +2 位作者 高勤峰 任贻超 王芳 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2015年第3期616-623,共8页
Three color variants of the sea cucumber,Apostichopus japonicus are recognized,the red one is highly valued in the market. When the red variant is cultured in ponds in China,its body color changes from red to celadon ... Three color variants of the sea cucumber,Apostichopus japonicus are recognized,the red one is highly valued in the market. When the red variant is cultured in ponds in China,its body color changes from red to celadon in 3–6 months. The effects of water depth and substrate color on the growth and body color of this animal were investigated. Juveniles of red A. japonicus were cultured in cages suspended at a range of water depths(20,50,100,150 and 200 cm). The specific growth rate of red sea cucumbers was significantly higher in animals cultured at deeper water layers compared with those grown at shallowers. Body weights were greatest for sea cucumbers cultured at a depth of 150 cm and their survival rates were highest at a depth of 200 cm. A scale to evaluate the color of red sea cucumbers(R value) was developed using a Pantone standard color card. All stocked animals in the 9-month trial retained a red color,however the red body color was much more intense in sea cucumbers cultured at shallower depths,while animals suspended in deeper layers became pale. In a separate trial,A. japonicus were cultured in suspended cages with seven different colored substrates. Substrate color had a significant effect on the growth and body-color of red A. japonicus. The yield were greatest for A. japonicus cultured on a yellow substrate,followed by green > white > orange > red > black and blue. All sea cucumbers in the 7-month trial retained a red color,although the red was most intense(highest R value) in animals cultured on a blue substrate and pale(lowest R value) for animals cultured on a green substrate. 展开更多
关键词 Apostichopusjaponicus water depth substrate color GROWTH body color
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Influence of La precursors on structure and properties of CeO_2-ZrO_2-Al_2O_3 composite oxides 被引量:1
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作者 You-feng LI Yue-hui HE +1 位作者 Guo-qing LIU Ling-wei ZENG 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2018年第4期739-747,共9页
Three La-doped CeO2-ZrO2-Al2O3(CZA)composite oxide samples,namely,CZA-I,CZA-II and CZA-III,were prepared following a co-precipitation method in the presence of La2O3,La(NO3)3-6H2O and H[La(EDTA)]-16H2O precursors,resp... Three La-doped CeO2-ZrO2-Al2O3(CZA)composite oxide samples,namely,CZA-I,CZA-II and CZA-III,were prepared following a co-precipitation method in the presence of La2O3,La(NO3)3-6H2O and H[La(EDTA)]-16H2O precursors,respectively.When the precursor samples are sintered at 1000°C,the as-prepared composite oxides mainly exhibit the CeO2-ZrO2 cubic fluorite phase,while theγ-Al2O3 andδ-Al2O3 phases appear when the precursor samples are subjected to sintering at 1100 and 1200°C.CZA-III exhibits improved redox properties after high-temperature treatment compared with CZA-I and CZA-II.CZA-III presents the largest surface area of 97.46 m2/g among the three CZAs when the CZA-III precursor sample is sintered at 1000°C.Furthermore,the corresponding oxygen storage capacity(OSC)is the largest with value of 400.27μmol/g when CZA-III precursor sample is sintered at 1000°C.Additionally,CZA-III exhibits the best thermal stability and the highest reduction temperature.However,by increasing the sintering temperature to 1200°C,there is a dramatic decline in the properties of surface area and OSC.And a decrease for CZA-III in surface area by 58.94%and a decrease of the OSC value by 74.56%are observed. 展开更多
关键词 La precursor ceria-zirconia solid solution composite oxide texture structure redox property
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A new germacranolide from Carpesium cernuum
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作者 曹建新 潘远江 +4 位作者 许重阳 黄利夏 马淑红 代常亮 高婉婉 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2005年第7期640-642,共3页
As a part of our interest in biologically active germacranolides from the genus Carpesium (Compositae), we have investigated the constituents of Carpesium cernuum. This paper reports the isolation and structural elu... As a part of our interest in biologically active germacranolides from the genus Carpesium (Compositae), we have investigated the constituents of Carpesium cernuum. This paper reports the isolation and structural elucidation of a new germacranolide, cernolide A (Compound 1), from the herb. The structure of Compound 1 was determined as 2α,3β-dihydroxy-9-angeloxygermacra-4-en-6,12-olide on the basis of spectral evidence. The skeleton of Compound 1 was elucidation by IR, MS, ^1H and ^13C NMR, COSY, HMQC and HMBC experiments. The stereochemistry of Compound 1 was deduced by ROESY spectral data. Finally, the procedures of extraction and isolation were described in detail. 展开更多
关键词 Carpesium cernuum COMPOSITAE SESQUITERPENOID 3β-dihydroxy-9-angeloxygermacra-4-en-6 12-olide
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Motion feature descriptor based moving objects segmentation
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作者 Yuan Hui Chang Yilin +2 位作者 Ma Yanzhuo Bai Donglin Lu Zhaoyang 《High Technology Letters》 EI CAS 2012年第1期84-89,共6页
A novel moving objects segmentation method is proposed in this paper. A modified three dimensional recursive search (3DRS) algorithm is used in order to obtain motion information accurately. A motion feature descrip... A novel moving objects segmentation method is proposed in this paper. A modified three dimensional recursive search (3DRS) algorithm is used in order to obtain motion information accurately. A motion feature descriptor (MFD) is designed to describe motion feature of each block in a picture based on motion intensity, motion in occlusion areas, and motion correlation among neighbouring blocks. Then, a fuzzy C-means clustering algorithm (FCM) is implemented based on those MFDs so as to segment moving objects. Moreover, a new parameter named as gathering degree is used to distinguish foreground moving objects and background motion. Experimental results demonstrate the effectiveness of the proposed method. 展开更多
关键词 motion estimation (ME) motion feature descriptor (MFD) fuzzy C-means clustering .moving objects segmentation video analysis
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Transmission electron microscopic study of the fine-grained vein matrix in the Suizhou L6 meteorite
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作者 Xie Xiande Wang Jianbo +2 位作者 Gu Xiangping Xiong Yi Jia Shuangfeng 《Acta Geochimica》 EI CAS CSCD 2016年第2期105-110,共6页
The mineralogy of shock vein matrix in the Suizhou meteorite has been investigated by optical and transmission electron microscopy. It was revealed that the vein matrix is composed of majorite-pyrope garnet, mag- aesi... The mineralogy of shock vein matrix in the Suizhou meteorite has been investigated by optical and transmission electron microscopy. It was revealed that the vein matrix is composed of majorite-pyrope garnet, mag- aesiowtistite, and ringwoodite, with FeNi-FeS inter- growths. The observation and character of ring-like selected electron diffraction (SAED) patterns indicate that Lhe idiomorphic garnet crystals in the vein matrix have different orientations. The polycrystalline nature of magnesiowtistite is also confirmed by a ring-like SAED pattern. Both garnet and magnesiowtistite crystals showed sharp Jiffraction spots, signifying the good crystallinity of these :wo minerals. The SAED pattern of cryptocrystalline 5ngwoodite shows only diffuse concentric diffraction tings. FeNi metal and troilite (FeS), which were molten during the shock event, occur in the matrix as fine eutectic FeNi-FeS intergrowths filling the interstices between garaet and magnesiowiistite grains. Based on the phase dia- gram of the Allende chondrite and the results of this TEM study, it is inferred that majorite-pyrope garnet first crystallized from the Suizhou chondritic melt at 22-26 GPa, Followed by crystallization of magnesiowtistite at 20-24 GPa, and then ringwoodite at 18-20 GPa. The eutectic intergrowths of FeNi-metal and troilite are proposed to have crystallized during meteorite cooling and solidified at the last stage of vein formation. 展开更多
关键词 Suizhou meteorite Shock vein matrix. High-pressure minerals Transmission electron microscopy
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Experimental investigation on combustion and unregulated emission characteristics of butanol-isomer/gasoline blends 被引量:3
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作者 LI Yuan-xu NING Zhi YAN Jun-hao 《Journal of Central South University》 SCIE EI CAS CSCD 2019年第8期2244-2258,共15页
Effects of butanol isomers on characteristics of combustion and emission were studied on PFI SI engine. Experiments were operated under the condition of 3 and 5 bar brake mean effective pressure (BMEP) engine loads an... Effects of butanol isomers on characteristics of combustion and emission were studied on PFI SI engine. Experiments were operated under the condition of 3 and 5 bar brake mean effective pressure (BMEP) engine loads and different equivalence ratios (φ=0.83-1.25) with engine speed of 1200 r/min using blends made of 70 vol.% gasoline and 30 vol.% butanol isomers (N30, S30, I30 and T30). The results indicated that compared with gasoline, all butanol isomer blends have higher cylinder pressure. N30 has the highest and most advanced peak pressure, and T30 shows a higher brake specific fuel consumption (BSFC) and lower brake thermal efficiency (BTE). N30 presents a lower UHC emissions and I30 has slightly higher CO emissions than other blends. For unregulated emissions, compared with gasoline, butanol isomer blends have higher acetaldehyde, and N30 produces a higher emission of 1,3-butadiene than other blends. A reduction in benzene, toluene, ethylbenzene and xylene (BTEX) has been found with butanol isomer blends. 展开更多
关键词 Butanol isomers unregulated emission combustion characteristics gas chromatograph SI engine
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Physically based analytical model for plateau in gate C-V characteristics of strained silicon pMOSFET 被引量:2
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作者 王斌 张鹤鸣 +3 位作者 胡辉勇 张玉明 周春宇 李妤晨 《Journal of Central South University》 SCIE EI CAS 2013年第9期2366-2371,共6页
A physically based analytical model was developed to predict the performance of the plateau observed in the gate C-V characteristics of strained-Si/SiGe pMOSFET.Experimental results were used to validate this model.Th... A physically based analytical model was developed to predict the performance of the plateau observed in the gate C-V characteristics of strained-Si/SiGe pMOSFET.Experimental results were used to validate this model.The extracted parameters from our model were tOX=20 nm,ND=1×1016cm 3,tSSi=13.2 nm,consistent with the experimental values.The results show that the simulation results agree with experimental data well.It is found that the plateau can be strongly affected by doping concentration,strained-Si layer thickness and mass fraction of Ge in the SiGe layer.The model has been implemented in the software for strained silicon MOSFET parameter extraction,and has great value in the design of the strained-Si/SiGe devices. 展开更多
关键词 strained-Si/SiGe PMOSFET gate C-V characteristics PLATEAU doping concentration strained-Si layer thickness mass fraction of Ge
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