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Preparation of a high-performance synthetic pitch from aromatic hydrocarbons containing N/Cl
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作者 ZHANG Yu-kun LIN Xiong-chao +3 位作者 GAO Hong-feng XI Wen-shuai WANG Cai-hong WANG Yong-gang 《新型炭材料(中英文)》 SCIE EI CAS CSCD 北大核心 2024年第4期655-667,共13页
The preparation of a synthetic pitch from aromatic monomers could easily regulate structure orientation at the molecu-lar level,which would be useful in fabrication.An isotropic synthetic pitch was prepared by a chlor... The preparation of a synthetic pitch from aromatic monomers could easily regulate structure orientation at the molecu-lar level,which would be useful in fabrication.An isotropic synthetic pitch was prepared by a chlorine-and/or nitrogen-induced sub-stitution polymerization reaction method using aromatic hydrocarbon precursors containing Cl and N,which for this study were chloromethyl naphthalene and quinoline.This method was verified by investigating the structural changes under different synthesis conditions,and the synthesis mechanism induced by aromatics containing Cl was also probed.The result shows that the pyridinic N in quinoline contains a lone pair of electrons,and is an effective active site to induce the polymerization reaction by coupling with aromatic hydrocarbons containing Cl.The reaction between such free radicals causes strong homopolymerization and oligomeriza-tion.A higher reaction temperature and longer reaction time significantly increased the degree of polymerization and thus increased the softening point of the pitch.A linear molecular structure was formed by the Cl substitution reaction,which produced a highly spinnable pitch with a softening point of 258.6℃,and carbon fibers with a tensile strength of 1163.82 MPa were obtained.This study provides a relatively simple and safe method for the preparation of high-quality spinnable pitch. 展开更多
关键词 QUINOLINE 1-Chloromethyl-naphthalene Synthetic pitch SPINNABILITY Carbon fiber
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Improvement Mechanism of Adhesion Performance of Anti-stripping Agents and Coupling Agents on Asphalt-Aggregate Interface Based on Molecular Dynamics
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作者 SONG Jing XIE Jianguang DAI Zexinyu 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2024年第S01期111-120,共10页
This study examined the mechanisms for improving the adhesion performance of the asphalt-aggregate interface with two anti-stripping agents and two coupling agents.The investigation of contact behavior between various... This study examined the mechanisms for improving the adhesion performance of the asphalt-aggregate interface with two anti-stripping agents and two coupling agents.The investigation of contact behavior between various asphalt-aggregate surfaces was conducted using molecular dynamics(MD)simulations.The interaction energy and the relative concentration distribution were employed as the parameters to analyze the enhancement mechanisms of anti-stripping agents and coupling agents on the asphalt-aggregate interface.Results indicated that the adhesion at the asphalt-aggregate interface could be strengthened by both anti-stripping agents and coupling agents.Anti-stripping agents primarily improve adhesion through the reinforcement of electrostatic attraction,while coupling agents primarily upgrade adhesion by strengthening the van der Waals.Hence,the molecular dynamics modeling and calculation techniques presented in this study can be utilized to elucidate the development mechanism of the asphalt-aggregate interface through the use of anti-stripping agents and coupling agents. 展开更多
关键词 asphalt-aggregate interface adhesion performance anti-stripping agents coupling agents molecular dynamics
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油炸马铃薯食品中发现丙烯酰胺的研究近况 被引量:7
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作者 邬应龙 何国庆 应铁进 《食品与发酵工业》 CAS CSCD 北大核心 2002年第7期71-75,共5页
对油炸或焙烤马铃薯食品中的丙烯酰胺含量、食品中丙烯酰胺含量的分析方法、丙烯酰胺毒性问题的最新研究结果进行了综述。现有研究结果表明 ,炸薯片、炸薯条中含有较高含量的丙烯酰胺 ,过度油炸会进一步增加薯条中的丙烯酰胺含量 ,而相... 对油炸或焙烤马铃薯食品中的丙烯酰胺含量、食品中丙烯酰胺含量的分析方法、丙烯酰胺毒性问题的最新研究结果进行了综述。现有研究结果表明 ,炸薯片、炸薯条中含有较高含量的丙烯酰胺 ,过度油炸会进一步增加薯条中的丙烯酰胺含量 ,而相应的生马铃薯原料与煮熟马铃薯中则不含丙烯酰胺。食品中丙烯酰胺含量的分析方法目前采用气相色谱 -质谱法 (GC MS)与液相色谱 串联质谱联用新技术 (LC/MS/MS) ,但食品中丙烯酰胺含量的分析方法、丙烯酰胺的毒理学研究仍在进一步发展中。 展开更多
关键词 油炸马铃薯食品 丙烯酰胺 分析方法 青性 气相色谱质谱法
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Laboratory evaluation of epoxy resin modified asphalt mixtures 被引量:13
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作者 钱振东 罗桑 王建伟 《Journal of Southeast University(English Edition)》 EI CAS 2007年第1期117-121,共5页
The pavement performance of epoxy resin modified asphalt mixtures was investigated by the Marshall test, the indirect tensile test, the rutting test, the three-pointed bending test and the composite beam fatigue test.... The pavement performance of epoxy resin modified asphalt mixtures was investigated by the Marshall test, the indirect tensile test, the rutting test, the three-pointed bending test and the composite beam fatigue test. In comparison with the performance of epoxy resin modified asphalt mixtures, the performance of stone matrix asphalt mixtures (SMA10) was also investigated. The rutting test and composite beam fatigue test results show that the epoxy resin modified asphalt mixtures can improve permanent deformation and fatigue characteristics. They also show lower temperature susceptibility and greater resistance to moisture damage compared to the SMA10. Findings from the research indicate that the epoxy resin modified asphalt mixture provides an optional material for the pavement of long-span steel bridges in China due to profound performance and economic advantages. 展开更多
关键词 epoxy resin modified asphalt epoxy resin modified asphalt mixture PAVEMENT strength performance
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Evaluation of modification effect of epoxy resin based on performance of asphalt mixtures 被引量:4
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作者 杨军 陆海珠 +1 位作者 袁登全 王建伟 《Journal of Southeast University(English Edition)》 EI CAS 2007年第1期122-126,共5页
Based on the analysis of the main failures discovered in pavement on steel deck plate and the demanding service condition of the pavement on steel deck, high-temperature rutting test, low-temperature bending test and ... Based on the analysis of the main failures discovered in pavement on steel deck plate and the demanding service condition of the pavement on steel deck, high-temperature rutting test, low-temperature bending test and controlled stress flexural fatigue test are used to study the performance of asphalt mixtures modified by epoxy resin including high-temperature stability, low-temperature cracking-resistance, and fatigue cracking-resistance, which are served to evaluate the modification effect of epoxy resin of different contents. With the addition of epoxy resin, all the three performances are improved greatly. However, when the amount of epoxy resin added is over a certain value, the modification effect will be stable with no extra benefit detected. Finally, in terms of the properties of the three respects, 20%, 30%, 30% are given separately as the proposal adding contents. 展开更多
关键词 pavement on steel deck plate content of epoxy resin asphalt mixtures modified by epoxy resin PERFORMANCE modification effect
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Construction controlling and strength increasing characteristics of locally developed epoxy asphalt mixture 被引量:7
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作者 陈春 钱振东 陈磊磊 《Journal of Southeast University(English Edition)》 EI CAS 2011年第1期61-64,共4页
The construction controlling elements,including construction performance at low ambient temperatures,reserved time ranges,and the strength increasing rule,for locally developed epoxy asphalt mixture(LDEAM) are studi... The construction controlling elements,including construction performance at low ambient temperatures,reserved time ranges,and the strength increasing rule,for locally developed epoxy asphalt mixture(LDEAM) are studied through laboratory tests.Air void and Marshall stability are chosen as the performance measures for evaluating the construction quality.The wheel rolling test is used to simulate the actual construction situations,while the Marshall test and the Brookfield viscosity test are adopted to study the strength increasing rule.The experimental results reveal that the LDEAM can be constructed under a low ambient temperature condition of 10℃,and its longest reserved time is 70 min at a reserved temperature of 120℃.Test also shows that the strength of the LDEAM increases with time and temperature before cured.Finally,the theoretical reason for the strength increasing rule is analyzed on the basis of the organic chemistry theory. 展开更多
关键词 construction characteristics locally developed epoxy asphalt strength increasing characteristics
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In situ synthesized Cu-ZSM-5/cordierite for reduction of NO 被引量:5
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作者 王建成 田东 +2 位作者 韩丽娜 常丽萍 鲍卫仁 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第2期353-358,共6页
ZSM-5 zeolites were directly synthesized on the surface of honeycomb cordierite substrates by hydrothermal method and certified by XRD and SEM techniques; the adhesion of ZSM-5 coatings was evaluated by ultrasonic vib... ZSM-5 zeolites were directly synthesized on the surface of honeycomb cordierite substrates by hydrothermal method and certified by XRD and SEM techniques; the adhesion of ZSM-5 coatings was evaluated by ultrasonic vibration. Cu-ZSM-5/cordierite monolithic catalyst was prepared by ion-exchange and impregnation method and applied for the selective catalytic reduction (SCR) of NO by NH3 using a simulated diesel exhaust. The results show that the cordierite surface is almost completely covered by ZSM-5 crystals and the crystallization time greatly impacts the loadings and adhesion of ZSM-5 coatings on substrate, the NOx removal rate over Cu-ZSM-5/cordierite is above 90% in a temperature range of 240-480℃. Moreover, Cu-ZSM-5/cordierite prepared by different methods shows a wide temperature window (240-540 ℃) with high NO removal activities. 展开更多
关键词 in situ synthesis Cu-ZSM-5/cordierite selective catalytic reduction NH3
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Anti-cracking mechanism of diatomite asphalt and diatomite asphalt mixture at low temperature 被引量:8
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作者 谭忆秋 单丽岩 +1 位作者 房军 张兴友 《Journal of Southeast University(English Edition)》 EI CAS 2009年第1期74-78,共5页
A kind of neat asphalt and three kinds of diatomite asphalt are tested using differential scanning calorimetry(DSC). The anti-cracking mechanism of diatomite asphalt is analyzed by DSC and the thermal stress restrai... A kind of neat asphalt and three kinds of diatomite asphalt are tested using differential scanning calorimetry(DSC). The anti-cracking mechanism of diatomite asphalt is analyzed by DSC and the thermal stress restrained specimen test(TSRST) of the asphalt mixtures. The results show that the low temperature performance of diatomite asphalt is better than that of neat asphalt. The glass transition temperature can reflect the low temperature performance of the diatomite asphalt better and has a good relationship with breaking temperatures. Besides, the TSRST, the bending test, the compressing test and the contraction coefficient test are used to study the low temperature performance of the diatomite asphalt mixture. The results prove that the low temperature performance of the diatomite asphalt mixture is better than that of the neat asphalt mixture. The critical bending strain energy density and the compressing strain energy density of the diatomite asphalt mixture are greater than those of the neat asphalt mixture. After adding diatomite to the asphalt mixture, the contraction coefficient is reduced. Based on the above results, the anti-cracking mechanism of the diatomite asphalt mixture is analyzed from the angle of contraction performance and breaking energy. 展开更多
关键词 diatomite asphalt low temperature performance glass transition temperature differential scanning calorimetry anticracking mechanism
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Rutting resistance of asphalt mixtures in the middle course 被引量:4
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作者 杨军 于良溟 +2 位作者 万军 陈军 钱国超 《Journal of Southeast University(English Edition)》 EI CAS 2006年第2期270-272,共3页
In order to improve the rutting resistance of asphalt mixtures in the middle course to reduce the rutting of asphalt pavement, the influence of different types of gradation with their own optimal asphaltaggregate rati... In order to improve the rutting resistance of asphalt mixtures in the middle course to reduce the rutting of asphalt pavement, the influence of different types of gradation with their own optimal asphaltaggregate ratios is analyzed. Some investigations are made out on the mixture in the middle course through the modified wheel tracking test in air bath and the Hamburg wheel tracking test (HWTT) in water bath, and the results of which are compared with the corresponding research in Germany. Results show that the Sup20 and the modified AC-20I have better performance than that of AC-20I under the same test conditions. In addition, the high-quality bitumen and hard aggregate can improve the rutting performance of the mixture in water-submerged conditions. The selection of modified asphalt, hard aggregate and a reasonable gradation are essential to the improvement of the rutting resistance of the mixtures used in the middle course. 展开更多
关键词 middle course RUTTING modified asphalt modified wheel tracking test Hamburg wheel tracking test
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Bond condition between surface layer and immediate layer in porous asphalt pavement 被引量:3
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作者 杨军 戴鹏 +3 位作者 于良溟 葛苏闽 刘清泉 钱国超 《Journal of Southeast University(English Edition)》 EI CAS 2007年第4期588-593,共6页
Through the shear tests on composite specimens using four different kinds of tack coat material (epoxy resin, SBS modified emulsified asphalt, SBS modified asphalt and H# bridge waterproof material), the bond condit... Through the shear tests on composite specimens using four different kinds of tack coat material (epoxy resin, SBS modified emulsified asphalt, SBS modified asphalt and H# bridge waterproof material), the bond condition between layers of porous asphalt pavement under traffic load, temperature variation and moisture situation is evaluated. The test results show that the bond strength decreases with the rise in temperature, and the relationship between shear strength and temperature can be expressed by a logarithm curve at a high reliability. Under the action of traffic load, the value of shear strength of the mixture right under the centre of the wheel track is smaller than that of other parts of the pavement. It is also found that some effects concerning moisture have comparative effects on the bonding of the two layers. Given all the results achieved during the study, it will be quite rewarding to make rational comparisons during selecting the sound type of tack coat. 展开更多
关键词 porous asphalt pavement waterproof and cohesive layer: shear strength
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Study on High Temperature Behaviour of Gussasphalt 被引量:11
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作者 杨军 Gharabaghy Cyrus Steinauer Bernhard 《Journal of Southeast University(English Edition)》 EI CAS 2002年第4期297-301,共5页
Rutting is one of the most damages in the asphalt surfaces for the orthotropic steel bridge decks. With Hamburg wheel tracking device, the suitable test conditions for Gussasphalt in Germany are pointed out, the high ... Rutting is one of the most damages in the asphalt surfaces for the orthotropic steel bridge decks. With Hamburg wheel tracking device, the suitable test conditions for Gussasphalt in Germany are pointed out, the high temperature behaviour of Gussasphalt with different binders are tested and compared. The polymer modified binder has higher resistance stability to rutting. The retained time and mixed frequency have obvious effects on Gussasphalt behaviour during Gussasphalt retained period. 展开更多
关键词 GUSSASPHALT high temperature behaviour Hamburg wheel tracking test polymer modified binder
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Seasonal Changes in Photosynthetic Characteristics of Ammopiptanthus mongolicus 被引量:43
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作者 李文瑞 冯金朝 +2 位作者 江天然 张立新 刘新民 《Acta Botanica Sinica》 CSCD 1999年第2期190-193,共4页
Seasonal changes in the photosynthetic characteristics of Ammopiptantus mongolicus (Maxim. )Chen f. were studied. When the net photosynthetic rate decreased with the elevation of air temperature, thestomatal conductan... Seasonal changes in the photosynthetic characteristics of Ammopiptantus mongolicus (Maxim. )Chen f. were studied. When the net photosynthetic rate decreased with the elevation of air temperature, thestomatal conductance and stomatal limitation value tended to decline simultaneously, while the interoellularCO2 concentration was increased. According to the two criteria discriminating the stomatal limitation of Photosynthesis suggeSted by Fmrquhar and Sharkey, the seasonal changes in these parameters indicated that the decrease in Pn may not be due to stomatal factor. These studies proved that the relative contents of the large subunit of Rubisco and the photochemical activities correlated with the seasonal changes in the net photosyntheticrate, whieh may show that these two factors contribute primarily to the seasonal changeS in CO2 assimilation. 展开更多
关键词 Net photosynthetic rate Stomatal conductance Intercellular CO2 concentration Stomatal limitation value RUBISCO Electron transport activity
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Development of overlay tester for fracture test of asphalt mixture 被引量:2
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作者 李兴海 黄卫 钱振东 《Journal of Southeast University(English Edition)》 EI CAS 2013年第3期294-299,共6页
To determine the fracture characteristics of asphalt mixture a novel fracture test with modified loading modes loading fixtures and the control system of the conventional overlay tester is implemented by the asphalt m... To determine the fracture characteristics of asphalt mixture a novel fracture test with modified loading modes loading fixtures and the control system of the conventional overlay tester is implemented by the asphalt material performance tester AMPT .In order to evaluate the validity of the proposed fracture test four different loading rates including 1 2 3 and 4 mm/min are examined in the AMPT. The results indicate that the fracture behavior is similar to creep at a low loading rate and does not show significant marginal tail extension at a high loading rate.It clearly shows the phase of crack initiation crack propagation and fracture at a loading rate of 3 mm/min. Besides eight fracture parameters such as fracture energy tensile strength and tensile modulus are applied to evaluate the fracture characteristics of asphalt mixture.Development of the overlay tester for the fracture test of asphalt mixture can be considered as a new fracture test of asphalt mixture. 展开更多
关键词 asphalt mixture fracture test overlay tester asphalt material performance tester (AMPT) fracture parame-ter
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Comparative Assessment of Genetic Diversity of Peanut (Arachis hypogaea L.)Genotypes with Various Levels of Resistance to Bacterial Wilt Through SSR and AFLP Analyses 被引量:12
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作者 姜慧芳 廖伯寿 +4 位作者 任小平 雷永 Emma Mace 傅廷栋 J.H.Crouch 《Journal of Genetics and Genomics》 SCIE CAS CSCD 北大核心 2007年第6期544-554,共11页
Bacterial wilt (BW) caused by Ralstonia solanacearum is an important constraint to peanut (Arachis hypogaea L.) production in several Asian and African countries, and planting BW-resistant cultivars is the most fe... Bacterial wilt (BW) caused by Ralstonia solanacearum is an important constraint to peanut (Arachis hypogaea L.) production in several Asian and African countries, and planting BW-resistant cultivars is the most feasible method for controlling the disease. Although several BW-resistant peanut germplasm accessions have been identified, the genetic diversity among these has not been properly investigated, which has impeded efficient utilization. In this study, the genetic relationships of 31 peanut genotypes with various levels of resistance to BW were assessed based on SSR and AFLP analyses. Twenty-nine of 78 SSR primers and 32 of 126 AFLP primer combinations employed in this study were polymorphic amongst the peanut genotypes tested. The SSR primers amplified 91 polymorphic loci in total with an average of 3.14 alleles per primer, and the AFLP primers amplified 72 polymorphic loci in total with an average of 2.25 alleles per primer. Four SSR primers (14H06, 7G02, 3A8, 16C6) and one AFLP primer (P1M62) were found to be most efficient in detecting diversity. The genetic distance between pairs of genotypes ranged from 0.12 to 0.94 with an average of 0.53 in the SSR data and from 0.06 to 0.57 with an average of 0.25 in the AFLP data. The SSR-based estimates of the genetic distance were generally larger than that based on the AFLP data. The genotypes belonging to subsp, fastigiata possessed wider diversity than that of subsp, hypogaea. The clustering of genotypes based on the SSR and AFLP data were similar but the SSR clustering was more consistent with morphological classification ofA. hypogaea. Optimum diverse genotypes of both subsp, hypogaea and subsp.fastigiata can be recommended based on this analysis for developing mapping populations and breeding for high yielding and resistant cultivars. 展开更多
关键词 PEANUT bacterial wilt resistance genetic diversity SSR AFLP
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Permanent deformation and deformation compliance of guss-asphalt for orthotropic steel deck plate surfacing 被引量:7
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作者 陈先华 黄卫 王建伟 《Journal of Southeast University(English Edition)》 EI CAS 2004年第3期360-363,共4页
Indentation test and bending test were adopted to investigate permanent deformation and deformation compliance of guss-asphalt for orthotropic steel deck plate. Factors of mastic Epure content, fine to coarse aggregat... Indentation test and bending test were adopted to investigate permanent deformation and deformation compliance of guss-asphalt for orthotropic steel deck plate. Factors of mastic Epure content, fine to coarse aggregate proportion, temperature and loading pressure were investigated. It is pointed out that mastic Epure content, temperature and loading pressure are the main factors influencing permanent deformation of guss-asphalt; fine to coarse aggregate proportion influences its maximum bending strain and crack energy at low temperature. The results indicate that there exists an optimum mastic Epure content, and a critical operation temperature as well as a critical loading pressure for guss-asphalt in operation. 展开更多
关键词 Bending (deformation) Concrete aggregates DEFORMATION Loading
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Study on low temperature performance of Gussasphalt on steel decks with hard bitumen 被引量:6
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作者 杨军 《Journal of Southeast University(English Edition)》 EI CAS 2003年第2期160-164,共5页
Using a Hamburg wheel-track test device, the resistance to rutting of Gussasphalt is tested and compared. Gussasphalt with hard bitumen has good resistance to rutting. The related resistance abilities to cracking at ... Using a Hamburg wheel-track test device, the resistance to rutting of Gussasphalt is tested and compared. Gussasphalt with hard bitumen has good resistance to rutting. The related resistance abilities to cracking at low temperature of Gussasphalt are tested and compared through flexural experiments and the composite structure fatigue test with temperature dropping. Gussasphalt with high performance polymer modified bitumen has a longer fatigue life and a lower breaking temperature; they can be used in the future surfaces for steel bridge decks in Germany. 展开更多
关键词 GUSSASPHALT surfaces for steel decks hard bitumen high performance polymer modified bitumen low temperature performance
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One-step hydrothermal synthesis of Cu-SAPO-34/cordierite and its catalytic performance on NO_x removal from diesel vehicles 被引量:2
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作者 王建成 陈影 +3 位作者 唐磊 鲍卫仁 常丽萍 韩丽娜 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第11期3330-3336,共7页
Cu-SAPO-34/cordierite catalysts were prepared via one-step hydrothermal synthesis method and their performances to remove NO x from the diesel vehicle exhaust were evaluated. The morphology, structure, Cu content and ... Cu-SAPO-34/cordierite catalysts were prepared via one-step hydrothermal synthesis method and their performances to remove NO x from the diesel vehicle exhaust were evaluated. The morphology, structure, Cu content and valence state were characterized by SEM, XRD, ICP and XPS, respectively. The experimental results show the active component Cu of the catalysts via in situ synthesis could significantly improve the selective catalytic reduction (SCR) activities of NOx and the optimal Cu content is in the range of 0.30%-0.40%(mass fraction). No N 2 O is detected by gas chromatograph (GC) during the evaluation process, which implies that NOx is almost entirely converted to N2 over Cu-SAPO-34/cordierite catalyst. The conversion rate of NOx to N2 by NH3 over catalyst could almost be up to 100%in the temperature range of 300-670 ℃with a space velocity of 12000 h-1 and it is still more than 60% at 300-620 ℃ under 36000 h-1. The catalysts also show the good hydrothermal and chemical stability at the atmosphere with H 2 O. 展开更多
关键词 in situ synthesis Cu-SAPO-34/cordierite NOx selective catalyst reduction NH3 diesel vehicle exhaust
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A Preliminary Study on Conservation Genetics of Endangered Vatica guangxiensis (Dipterocarpaceae) 被引量:10
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作者 李巧明 许再富 何田华 《Acta Botanica Sinica》 CSCD 2002年第2期246-249,共4页
运用 2 0个 10碱基随机引物 ,对中国龙脑香科 (Dipterocarpaceae)特有的珍稀濒危植物版纳青梅 (VaticaguangxiensisX .L .Mo)进行了RAPD多态性分析。 3个自然居群和 1个迁地保护居群 (分布于云南和广西 )共扩增出2 31个位点 ,多态位点... 运用 2 0个 10碱基随机引物 ,对中国龙脑香科 (Dipterocarpaceae)特有的珍稀濒危植物版纳青梅 (VaticaguangxiensisX .L .Mo)进行了RAPD多态性分析。 3个自然居群和 1个迁地保护居群 (分布于云南和广西 )共扩增出2 31个位点 ,多态位点所占比例 (PPB)为 5 3.6 8% ;观察等位基因数na =1.5 36 8,有效等位基因数ne =1.2 878,Nei基因多样性指数h为 0 .16 86 ,居群内的遗传多样性水平较低。基于AMOVA和POPGENE的结果均表明居群内的遗传变异大于居群间的遗传变异。居群内的遗传变异为 5 5 .0 9% ,居群间的变异为 44 .91% (AMOVA) ;基因分化系数Gst为 0 .3746 (POPGENE) ,表明居群间存在高水平的遗传分化。研究结果对该濒危植物的保护有重要意义。考虑到低水平的遗传多样性和高水平的居群分化 ,通过居群间种子和幼苗的交换来促进基因流是可行的保护方案。迁地保护居群 (ML)不具最高的遗传多样性 ,表明为了保护此濒危物种的全部遗传变异 。 展开更多
关键词 Vatica guangxiensis RAPD genetic diversity conservation biology
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Genetic Diversity of SSR Markers in Cultivated Hordeum vulgare L.in Qinghai Province 被引量:1
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作者 田海宁 杨菁 何桂芳 《Agricultural Science & Technology》 CAS 2011年第1期70-73,共4页
[Objective]The aim was to analyze genetic diversity of SSR markers in Hordeum vulgare L.in Qinghai Province and lay a foundation for screening and protecting some excellent H.vulgare cultivars.[Method]SSR markers were... [Objective]The aim was to analyze genetic diversity of SSR markers in Hordeum vulgare L.in Qinghai Province and lay a foundation for screening and protecting some excellent H.vulgare cultivars.[Method]SSR markers were used to evaluate the genetic diversity of 42 cultivated H.vulgare from Qinghai Province.[Result]42 H.vulgare showed polymorphism in 7 SSR markers locus.A total of 24 alleles were identified,and the number of alleles per locus ranged from 1 to 6,with an average of 3.0.According to SSR markers polymorphism,42 H.vulgare could be divided into 4 groups,namely I,II,III and IV.[Result]The study indicated that cultivated H.vulgare from Qinghai Province is rich in genetic diversity,which will provide reference for selecting parent of H.vulgare breeding. 展开更多
关键词 Qinghai Province Cultivated Hordeum vulgare L. SSR markers Genetic diversity
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Relationship between trophic component of different poplar strains and occurrence of Saperda poplnea
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作者 高长启 孙守慧 +8 位作者 任晓光 宋丽文 张晓军 戴万琢 肖辉 庄翠云 易德国 朱振宇 任海波 《Journal of Forestry Research》 SCIE CAS CSCD 2001年第4期263-265,278,共4页
An experimental area of poplar was established in Songyuan of Jilin Province in 1999 for testing the resistance of different poplar stains to Saperda poplnea. Incidence of S. poplnea on ten poplar strains were investi... An experimental area of poplar was established in Songyuan of Jilin Province in 1999 for testing the resistance of different poplar stains to Saperda poplnea. Incidence of S. poplnea on ten poplar strains were investigated, and the main trophic component of branches of these poplar trees were measured and analyzed in April 2001. The results showed that there existed significant difference in population size of S. poplnea on different poplar strains, and the branches of these poplar strains have significant difference in nutrient component and content of amino acids. The population size of this pest had a significantly positive correlation with dissolvable total sugar and water content but had no significant correlation with content of total nitrogen and protein nitrogen. 展开更多
关键词 Saperda poplnea Poplar strains Pest resistance
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