期刊文献+
共找到157篇文章
< 1 2 8 >
每页显示 20 50 100
Increased Endogenous Methyl Jasmonate Altered Leaf and Root Development in Transgenic Soybean Plants 被引量:7
1
作者 薛仁镐 张标 《Journal of Genetics and Genomics》 SCIE CAS CSCD 北大核心 2007年第4期339-346,共8页
Methyl jasmonate (MeJA) is a plant-signaling molecule that regulates plant morphogenesis and expression of plant defense genes. To determine the role of the endogenous MeJA levels in the development of plants, trans... Methyl jasmonate (MeJA) is a plant-signaling molecule that regulates plant morphogenesis and expression of plant defense genes. To determine the role of the endogenous MeJA levels in the development of plants, transgenic soybean [Glycine max (L.) Merrill] plants harboring NTR1 gene encoding for jasmonic acid carboxyl methyltransferase (JMT) were produced. The activation of NTR1 gene expression resulted in the production of MeJA. Overexpression of the NTR1 cDNA under the regulation of cauliflower mosaic virus (CaMV) 35S promoter in the transgenic soybean plants was confirmed using Northern blot analysis. The significant differences in leaf and root growth patterns were observed between the transgenic plants and the wild-type plants. The leaves of the transgenic plants were slightly elongated in length but dramatically narrowed in width compared with the nontrans-formed wild-type plants. In addition, elongation of primary root was inhibited in the overexpressed transgenic soybean plantlets, whereas the development of lateral root was stimulated relative to the nontransformed plants. The leaves of the transgenic plants showed 2-2.5-fold higher levels of MeJA than the control plants. These results indicated that the increased endogenous levels of MeJA is involved in regulation of morphogenesis in soybean plants. 展开更多
关键词 methyl jasmonate MORPHOGENESIS NTR1 OVEREXPRESSION SOYBEAN
下载PDF
Group Size and Composition of Black-and-White Snub-nosed Monkey (Rhinopithecus bieti) Estimated by Faecesof Sleeping Sites at Baima Snow Mountain 被引量:8
2
作者 崔亮伟 钟泰 +1 位作者 肖林 肖文 《Zoological Research》 CAS CSCD 北大核心 2006年第4期337-343,共7页
This study was designed to introduce a new method of estimating group size and composition of black-andwhite snub-nosed monkeys (Rhinopithecus bieti ) on the basis of faecal amount at sleeping sites at Mt. Baima Nat... This study was designed to introduce a new method of estimating group size and composition of black-andwhite snub-nosed monkeys (Rhinopithecus bieti ) on the basis of faecal amount at sleeping sites at Mt. Baima Nature Reserve. The monkeys spend nights in the form of one-male, multi-female units (OMUs) and all-male units (AMU), and their faecal pellets can be classified into three categories: adult males (the largest), adult females (moderate) and immatures (the smallest) based on their size. Total pellets were counted under sleeping trees used for two nights at Nanren village (99°04′E, 28°34′N, northwest of Yunnan Province, China) in each of four seasons in 2000- 2001. Moreover, data on group composition were collected when the monkeys were passing through an open gully in November 2001. Since the number of adults in OMUs shows a positive significant correlation with the amount of pellets amount in each season, the mean number of feces produced per night per individual is the slope of the regression lines. Thus, group size and composition can be relatively reliably and accurately estimated by the faeces under trees compared with the previous methods of estimation, including the use of monkeys' activities and tracks such as broken branches on steep slopes, in deep gorges and under lower visibility. The use of pellets for population estimates displayed 9.4% deviation in regards to population size of adult females. Some causes of the bias were also discussed. The method might be applicable to other monkey groups of this species if their habitats and main foods are similar to those of the study group. 展开更多
关键词 FECES Group composition Group size Rhinopithecus bieti Sleeping site
下载PDF
College English autonomous teaching and learning research and practice 被引量:1
3
作者 高鹏 时真妹 肖亮 《Sino-US English Teaching》 2009年第7期1-7,共7页
This paper intends to promote a college English autonomous teaching and learning approach by introducing the whole process of its implementation and feedback from the learners. The theoretical and practical framework ... This paper intends to promote a college English autonomous teaching and learning approach by introducing the whole process of its implementation and feedback from the learners. The theoretical and practical framework of this approach is: with multiple autonomous learning research and practice models as its core, with process syllabus as its guidance, with task-based teaching as its essential principle, with group cooperation and reciprocal learning as its means, with extracurricular activities, online learning and self-access center as its learning environment, with formative assessment system as its guarantee and with cultivation of learners' comprehensive English practical skills and autonomy as its goal. Through this approach, we provide the learners with a favorable learning environment where they can learn by themselves and learn by reflection and practice so that they can learn how to learn and how to behave and how to survive. 展开更多
关键词 autonomous learning process syllabus cooperative learning
下载PDF
Heterogeneous Uptake of Hydrogen Peroxide on Mineral Oxides 被引量:3
4
作者 王炜罡 葛茂发 孙巧 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2011年第5期515-520,I0003,共7页
The interaction of mineral oxides (α-A12O3, MgO, Fe2O3, and SiO2) with hydrogen peroxide was investigated using the Knudsen cell reactor. The initial reactive uptake coefficients for tile commercially available pow... The interaction of mineral oxides (α-A12O3, MgO, Fe2O3, and SiO2) with hydrogen peroxide was investigated using the Knudsen cell reactor. The initial reactive uptake coefficients for tile commercially available powders are measured as (1.00±0.11)×10-4 for α-A1203, (1.66±0.23)×10-4 for MgO, (9.70±1.95)×10-5 for Fe203, and (5.22±0.9)×10-5 for SiO2. These metal oxide powders exhibit some catalytic behavior toward the decomposition of hydrogen peroxide excluding SiO2. H2O2 can be destroyed on Fe2O3 surface and O2 is formed. The experimental results suggest that the heterogeneous loss on mineral surface can represent an important sink of hydrogen peroxide. 展开更多
关键词 KINETICS Hydrogen peroxide Heterogeneous uptake Atmospheric lifetime
下载PDF
A New Structure for a CMOS Audio Power AMP with Extremely Low THD and Low Power Consumption 被引量:1
5
作者 曹政新 熊绍珍 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2006年第9期1552-1556,共5页
A new system-corrected CMOS audio power AMP is presented. Consisting of four single-end OPAs,this structure is a pseudo-differential system. Compared to conventional CMOS power AMPs, it has the merits of low power con... A new system-corrected CMOS audio power AMP is presented. Consisting of four single-end OPAs,this structure is a pseudo-differential system. Compared to conventional CMOS power AMPs, it has the merits of low power consumption, extremely low THD,easy compensation, and good driving capability. With 1st silicon 0.25μm 1P4M CMOS technology and a 3V power supply,the output range can be 4Vpp when driving an 8Ω‖ 300pF load, while its power dissipation is less than 3mW. The THD is better than 0. 003% at 1kHz. A new over-current protection circuit, which can effectively protect the power output circuits on the chip, is also demonstrated. 展开更多
关键词 system-corrected structure CMOS power AMP over-current protection
下载PDF
Molecular Cloning, Escherichia coli Expression and Genomic Organization of Squalene Synthase Gene from Artemisia annua 被引量:5
6
作者 刘彦 叶和春 +1 位作者 王红 李国凤 《Acta Botanica Sinica》 CSCD 2003年第5期608-613,共6页
A 1 539 by squalene synthase (AaSQS) cDNA was cloned from a high-yield Artemisia annua L. strain 001 by reverse transcription-polymerise chain reaction (RT-PCR). The amino acid sequence of AaSQS is 70%, 77%, 44% and 3... A 1 539 by squalene synthase (AaSQS) cDNA was cloned from a high-yield Artemisia annua L. strain 001 by reverse transcription-polymerise chain reaction (RT-PCR). The amino acid sequence of AaSQS is 70%, 77%, 44% and 39%a identical to that of squalene synthases from Arabidopsis thaliana, tobacco, human and yeast, respectively. The AaSQS genomic DNA has a complex organization containing 14 exons and 13 introns. Full-length or C-terminal truncated cDNA was subcloned into prokaryotic expression vector pET30a and the constructed plasmid was introduced to Escherichia coli strain BL21 (DE3) for induced overexpression. No squalene synthase protein with expected molecular mass was observed in E. cola containing the putative full-length squalene synthase cDNA, however, overexpression in E. coli was achieved by truncating 30 amino acids of hydrophobic region at the carboxy terminus. 展开更多
关键词 Artemisia annua squalene synthase Escherachia coli overexpression genomic organization CLONING
下载PDF
Responses of Membrane Lipid Peroxidation and Endogenous Hormones of Soybean Seedlings to UV-B Radiation and Rare Earth 被引量:7
7
作者 闫生荣 杨春和 +2 位作者 张跃群 花海蓉 蒋云霞 《Agricultural Science & Technology》 CAS 2009年第6期72-75,90,共5页
[ Objective] The aim was to provide strategies for development of rare earth and control of environmental pollution. [ Method] Responses of membrane lipid peroxidation and endogenous hormones of soybean seedlings to U... [ Objective] The aim was to provide strategies for development of rare earth and control of environmental pollution. [ Method] Responses of membrane lipid peroxidation and endogenous hormones of soybean seedlings to UV-B radiation and rare earth were studied through hydroponics in laboratory. [ Result] The results showed that under irradiation of UV-B( T1-0.15 W/m^2 and T2-0.45 W/m^2), chlorophyll and indole-3-acetic acid(IAA) contents firstly decreased during the stress phase (1 -5 d) and then increased during the restoration phase (6 -9 d) while contents of malonadialdehyde(MDA) and abscisic acid(ABA) gradually increased during the imposition of UV-B radiation (1 -5 d) and subsequently decreased during recovery from UV-B stress (6 -9 d) . With adding of La (III) with the concentration of 20 mg · L^-1 , the decline/dse trend of chlorophyll, IAA, MDA and ABA contents was slowed down during the stress period while the rise/decline speed was accelerated during the recovery period. [ Conclusion] It suggests that the regulation of La ( III ) on membrane lipid peroxidation and endogenous hormones could increase chlorophyll and IAA contents, improve the metabolism of reactive oxygen species ( ROS), inhibit membrane lipid peroxidation, decrease the accumulation amount of ABA and alleviate injury of UV-B radiation to soybean seedlings. Further, the protective potential of La ( III ) was better under low UV-B radiation than under high one. 展开更多
关键词 La III UV-B radiation Soybean seedlings Membrane lipid peroxidation Endogenous hormones
下载PDF
Design of an OP-AMP Based on a LDO Regulator 被引量:4
8
作者 樊华 冯全源 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2005年第10期1905-1909,共5页
An operational amplifier (OP-AMP) with a ground current of about 0.6μA is presented. Moreover, this amplifier reaps the benefits of incorporating a foldback current limiting circuit,which enables the low-dropout vo... An operational amplifier (OP-AMP) with a ground current of about 0.6μA is presented. Moreover, this amplifier reaps the benefits of incorporating a foldback current limiting circuit,which enables the low-dropout voltage regulator without the need of a special current limiting subblock. Therefore,the object of ultra-low power is realized because of a great reduction in transistors and current limbs. 展开更多
关键词 operational amplifier ground current LDO foldback current limiter
下载PDF
Construction analysis on integral lifting of steel structure by the vector form intrinsic finite element 被引量:2
9
作者 朱明亮 陈雪琪 郭正兴 《Journal of Southeast University(English Edition)》 EI CAS 2016年第4期451-456,共6页
A newnumerical method based on vector form intrinsic finite element(VFIFE) is proposed to simulate the integral lifting process of steel structures. First, in order to verify the validity of the VFIFE method, taking... A newnumerical method based on vector form intrinsic finite element(VFIFE) is proposed to simulate the integral lifting process of steel structures. First, in order to verify the validity of the VFIFE method, taking the steel gallery between the integrated building and the attached building of Nanjing M obile Communication Buildings for example, the static analysis was carried out and the corresponding results were compared with the results achieved by the traditional finite element method. Then, according to the characteristics of dynamic construction of steel structure integral lifting, the tension cable element was employed to simulate the behavior of dynamic construction. The VFIFE method avoids the iterative solution of the stiffness matrix and the singularity problems. Therefore, it is simple to simulate the complete process of steel structure lifting construction.Finally, by using the VFIFE, the displacement and internal force time history curves of the steel structures under different lifting speeds are obtained. The results show that the lifting speed has influence on the lifting force, the internal force, and the displacement of the structure. In the case of normal lifting speed, the dynamic magnification factor of 1. 5 is safe and reasonable for practical application. 展开更多
关键词 integral lifting vector form intrinsic finite element(VFIFE) steel gallery whole process of construction dynamic magnification factor
下载PDF
Bioinformatics Analysis on B cell Epitopes of Rice Allergen RAG1 被引量:1
10
作者 李燕芳 何颖 邹泽红 《Agricultural Science & Technology》 CAS 2012年第2期304-306,共3页
[Objective] To predict the secondary structure and B cell epitopes of the rice major allergen RAG1. [Method] The amino acid sequence of rice allergen RAG1 was acquired from Expasy protein database. The secondary struc... [Objective] To predict the secondary structure and B cell epitopes of the rice major allergen RAG1. [Method] The amino acid sequence of rice allergen RAG1 was acquired from Expasy protein database. The secondary structure of RAG1 was predicted by DNAStar Protean software with Gamier-Robson program, Chou-Fasman program and Karplus-Schulz program; the B cell epitopes of RAG1 was predicted with the Kyte Doolittle hydrophilic program, Emini surface accessibility program and Jameson-Wolf antigenic index program. [Result] The predictions on secondary structure and B cell epitopes showed that the regions of 33-44, 119-129, 155-163 were the dominant B cell epitopes. [Conclusion] This study predicted the potential dominant B cell epitopes in rice allergen RAG1 by comprehensive use of multi-methods and multi-parameters, and provided a theoretical basis for further researches on identification, antigen modification and epitope vaccine design of RAG1 B cell epitopes. 展开更多
关键词 Rice allergen RAG1 Secondary structure B cell epitopes
下载PDF
Key Issues on Cryospheric Changes,Trends and Their Impacts 被引量:3
11
作者 Dahe Qin Yongjian Ding 《Advances in Climate Change Research》 SCIE 2010年第1期1-10,共10页
On the basis of analyzing the importance of cryospheric researches in China and current status of cryospheric sciences in the world, this paper addresses key issues and main contents of present cryospheric sciences in... On the basis of analyzing the importance of cryospheric researches in China and current status of cryospheric sciences in the world, this paper addresses key issues and main contents of present cryospheric sciences in China. The key issues currently addressed are: i) mechanisms of different types of glaciers in response to climate change and the scale-conversion in water resources assessments; ii) modeling of water and heat exchanges between frozen soil and vegetation; iii) parameterization of physical processes in cryosphere as well as coupling with climate models. To gain full clarification of these key issues, works of the following three aspects should be highlighted, i.e., cryospheric processes and responses to climate change, influences of cryospheric changes, and adaptation strategies for cryospheric changes. 展开更多
关键词 CRYOSPHERE climate change IMPACT water resources
下载PDF
Improvement of Isomerization Process of Crude Isoamylene with Tertiary-amyl-alcohol Addition 被引量:1
12
作者 徐泽辉 夏蓉晖 +2 位作者 郭世卓 范存良 房鼎业 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2009年第5期761-766,共6页
The present work contributed to a new developed production method for enhancing the quality of isoamylene (IA) by adding a small amount of tertiary amyl alcohol (TAA) to the catalyst of strong acid cation exchange... The present work contributed to a new developed production method for enhancing the quality of isoamylene (IA) by adding a small amount of tertiary amyl alcohol (TAA) to the catalyst of strong acid cation exchange resin. TAA improved the selectivity of 2-methyl-2-butene (2M2B) at a high conversion level for the isomerization of IA. Compared with the other results from the current IA units, the conversion of 2-methyl- 1-butene (2M1B), the mass ratio of 2M2B to 2M1B and the selectivity of 2M2B were increased from 0.5474, 7.32 and 0.6864 to 0.72, 12 and 0.95, respectively, while the dimers content in the products decreased from 4.38% to below 1.0%. Optimized conditions for IA isomerization consisted of temperature between 28 and 33℃ and system pressure of 0.5 MPa, weight hourly space velocity of 8.0 h-1 with TAA mass fraction of 0.7%-0.9% in raw material. The results in lab supported bases for the developed process in industrial application which was later proved to be successful. In addition, a possible mechanism of the isomerization process was speculated to propose a key step of water formation in the TAA-added isomerization process and a verified experiment was conducted to support this speculation. 展开更多
关键词 isoamylene 2-methyl-1-butene 2-methyl-2-butene isomerization process tertiary amyl alcohol
下载PDF
An extra embryonic phase in the true freshwater crab Sinopotamon yangtsekiense Bott,1967(Decapoda,Potamidae) 被引量:1
13
作者 吴惠仙 薛俊增 CUMBERLIDGE Neil 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2010年第4期725-730,共6页
The true freshwater crabs(Crustacea,Decapoda,Brachyura) are highly adapted to life in freshwater and complete their life cycle entirely independently of sea water.All true freshwater crabs exhibit direct development a... The true freshwater crabs(Crustacea,Decapoda,Brachyura) are highly adapted to life in freshwater and complete their life cycle entirely independently of sea water.All true freshwater crabs exhibit direct development and lack the free-living larval forms(zoea and megalopa) typical of most other brachyurans.After a prolonged embryonic period(during which they pass through the typical brachyuran larval forms embryologically) the eggs of true freshwater crabs hatch to produce juvenile(hatchling) crabs.We provide here the first report and description of the continuous record of embryonic development from egg-laying up to hatching in the Chinese true freshwater crab Sinopotamon yangtsekiense Bott,1967(Potamoidea,Potamidae).Direct development(complete secondary embryonization) in S.yangtsekiense was observed to take 77 days and to include an additional embryonic phase(termed here the egg-juvenile-crab) that occurs in the embryo between the imprisoned megalopa and the newly-emerged juvenile(hatchling) crab.This is significant because the only other freshwater crab whose embryonic development has been studied in detail is Potamon fluviatilis(Potamidae) which takes 45-47 days and involves only nine embryonic stages. 展开更多
关键词 true freshwater crab Sinopotamon yangtsekiense embryonic development egg larvae
下载PDF
Large Deviation Theorem for Empirical Measures of Degenerate Diffusion Processes
14
作者 刘秀芹 席福宝 《Journal of Beijing Institute of Technology》 EI CAS 2001年第3期233-239,共7页
A class of multi dimensional degenerate diffusion processes X ε(t) in R r(r≥2) are considered and the asymptotic properties of empirical measures are investigated; here X ε(t) saitisfies the stochastic differen... A class of multi dimensional degenerate diffusion processes X ε(t) in R r(r≥2) are considered and the asymptotic properties of empirical measures are investigated; here X ε(t) saitisfies the stochastic differential equation dX ε(t)=σ(X ε(t)) d W(t)+B(X ε(t)) d t+ εσ~(X ε(t)) d W(t),ε>0. X ε(t) are small random perturbations of the degenerate diffusion process X(t), which satisfies the stochastic differential equation dX(t)=σ(X(t)) d W(t)+B(X(t)) d t. A large deviation theorem for projection measures ν on R r-n (n<r) of empirical measures μ are proved 展开更多
关键词 empirical measures large deviation diffusion process
下载PDF
Mechanisms of Inhibitory Effects of Breviscapine on Lipid Peroxidation in Rat Brain Mitochondria 被引量:1
15
作者 陈小夏 何冰 陈一岳 《Journal of Chinese Pharmaceutical Sciences》 CAS 1998年第4期42-46,共5页
The mechanisms by which breviscapine (Bre) inhibits the lipid preoxidation in rat brain mitochondria were investigated. The mitochondrial lipid peroxidation of rat brain induced by oxygen free radical was measured by ... The mechanisms by which breviscapine (Bre) inhibits the lipid preoxidation in rat brain mitochondria were investigated. The mitochondrial lipid peroxidation of rat brain induced by oxygen free radical was measured by thiobarbituric acid spectrophotometry. The chelating activities of Bre for Fe 2+ were tested by differential spectrum. Superoxide anion (O 2)from xanthine xanthine oxidase (Xan XO) system and hydroxyl radical (·OH) from FeSO 4 H 2O 2 system were determined with spectrophotometry. It was found that Bre could effectively inhibit the lipid peroxidation of brain mitochondria induced by free radicals driven from Xan XO and FeSO 4 H 2O 2 system. The IC 50 of Bre were 93 01 μmol·L -1 for Xan XO system and 62 18 μmol·L -1 for FeSO 4 H 2O 2 system. Bre also scavenged O 2 and ·OH produced by Xan XO and FeSO 4 H 2O 2 systems. The IC 50 of Bre were 32 63 μmol·L -1 for O - 2 and 20 22 μmol·L -1 for ·OH. Furthermore, the chelating Fe 2+ activity of Bre was shown. It may be concluded that Bre inhibited lipid peroxidation at different stages of the reaction of oxygen free redial with the mitochondria membrane: (1) the formation of ·OH; (2) the initiation of the lipid peroxidation, by chelating Fe 2+ and scavenging O 2 as well as ·OH. The scavenging oxygen free radicals and chelating iron are the mechanisms of inhibitory effect of Bre on lipid peroxidation. 展开更多
关键词 BREVISCAPINE Brain mitochondria Lipid peroxidation Oxygen free radical CHELATOR
全文增补中
Investigation on Characteristics and the Improving Method of Double Loop Optical Buffer 被引量:1
16
作者 王拥军 吴重庆 +5 位作者 王智 杨双收 赵爽 王亚平 疏达 赵曦 《Chinese Physics Letters》 SCIE CAS CSCD 2009年第4期131-134,共4页
We establish an equivalent cascaded semiconductor optical amplifier system model to analyze the characteristics of the double loop optical buffer (DLOB). The theoretical analysis finds that the performance of the DL... We establish an equivalent cascaded semiconductor optical amplifier system model to analyze the characteristics of the double loop optical buffer (DLOB). The theoretical analysis finds that the performance of the DLOB can be improved by inserted amplifying process in an interval of some cycles. The experiment demonstrates that the buffered cycles can be improved from 20 to 50 and the bit error rate is less than 10-9 by inserting amplifying process in an interval of about 10 cycles. 展开更多
关键词 gamma-ray bursts GAMMA-RAYS RELATIVITY
下载PDF
Mechanical properties of porous titanium with different distributions of pore size 被引量:12
17
《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第8期2317-2322,共6页
To satisfy the mechanical and biological requirement of porous bone substitutes, porous Ti with two different pore sizes designed in advance was fabricated by the space-holder sintering process. Mechanical properties ... To satisfy the mechanical and biological requirement of porous bone substitutes, porous Ti with two different pore sizes designed in advance was fabricated by the space-holder sintering process. Mechanical properties of the porous Ti were explored via room temperature compressive tests. The pore sizes and shapes are uniform throughout the specimens with porosities ranging from 36% to 63%. The compression strength and the elastic modulus are in the range from 94.05 to 468.57 MPa and 2.662 to 18 GPa, respectively. It is worth noting that the relationship between the compressive strength and the porosities is completely linear relation beyond the effect of pore size distributions on the mechanical properties. The value of the constant C achieved from the Gibson-Ashby model suggests that the pore sizes affect the yield strength of the porous Ti and the values of density exponent (n) for porous Ti with two different pore sizes are higher than 2, which suggests that the deformation mode of the porous Ti with a porosity ranging from 36% to 63% is mainly buckling of the cell struts. 展开更多
关键词 porous Ti pore size distributions mechanical properties density exponent BIOMATERIALS
下载PDF
Removal of Nitrophenols by Adsorption Using β-Cyclodextrin Modified Zeolites 被引量:8
18
作者 李效红 赵保卫 +1 位作者 朱琨 郝学奎 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2011年第6期938-943,共6页
Removal of nitrophenols (NPs) from aqueous solutions through the adsorption process by using cationic β-cyclodextrin (CCD) modified zeolite (CCDMZ) was investigated. The effects of particle size, contact time, ... Removal of nitrophenols (NPs) from aqueous solutions through the adsorption process by using cationic β-cyclodextrin (CCD) modified zeolite (CCDMZ) was investigated. The effects of particle size, contact time, solution pH values and sodium chloride content in the aqueous on adsorption capacity were evaluated through a series of batch experiments. The results showed that CCDMZ had a higher adsorption capacity for removing NPs at a size fraction of 0.45-0.9 mm while adsorption of NPs on CCDMZ reached equilibrium within 60 min. The adsorption process was apparently influenced by pH values and sodium chloride content in aqueous solution. To ascertain the mechanisms of sorption, the experimental data were modeled by using the pseudo-first and pseudo-second order kinetic equations, and the results indicated that the adsorption kinetics of NPs on CCDMZ well-matched with the pseudo-second order rate expression. 展开更多
关键词 ADSORPTION ZEOLITE MODIFICATION NITROPHENOLS adsorption kinetics
下载PDF
Nonlinear characteristics of induced spontaneous combustion process of sulfide ores 被引量:2
19
作者 潘伟 吴超 +2 位作者 李孜军 石英 杨月平 《Journal of Central South University》 SCIE EI CAS CSCD 2016年第12期3284-3292,共9页
To investigate the relationship between nonlinear parameters and spontaneous combustion tendency of sulfide ores, nine different sulfide ore samples were taken from a pyrite mine in China, and induced spontaneous comb... To investigate the relationship between nonlinear parameters and spontaneous combustion tendency of sulfide ores, nine different sulfide ore samples were taken from a pyrite mine in China, and induced spontaneous combustion experiment was carried out in the laboratory. Different stages of the induced spontaneous combustion process were studied by integrating wavelet technology and nonlinear dynamics theory. The results show that ignition points of all the ore samples are above 330 ℃, indicating that sulfide ores of the pyrite mine are difficult to combust spontaneously under normal mining conditions. Spontaneous combustion process includes three stages: incubation stage, development stage and approaching stage. The average temperature rising rate of the three stages are 1.0 ~C/min, 2.0 ~C/min and 4.2 ~C/min, respectively. During the spontaneous combustion process, mean values of approximate entropy and correlation dimension increase at first, and then decrease in the following stage. The mean value of the maximum Lyapunov exponent increases with the passage of reaction time. In a whole, correlation among the three nonlinear parameters firstly weakens, then enhances, and the best correlation period is at approaching stage. As ignition point increases, the maximum Lyapunov exponent of approaching stage decreases. Therefore, combustible tendency of sulfide ores could be qualitatively evaluated based on the maximum Lyapunov exponent of this stage. 展开更多
关键词 sulfide ores induced spontaneous combustion nonlinear parameters ignition point maximum Lyapunov exponent
下载PDF
Mesalamine hypersensitivity and Kounis syndrome in a pediatric ulcerative colitis patient 被引量:1
20
作者 Geoge N Kounis Sophia A Kouni +1 位作者 George Hahalis Nicholas G Kounis 《World Journal of Gastroenterology》 SCIE CAS CSCD 2008年第46期7141-7142,共2页
5-aminosalicylic acid (mesalamine) rarely induces hyper- sensitivity reactions. If chest pain associated with atypical electrocardiographic changes are seen during its administration, one should always bear in mind ... 5-aminosalicylic acid (mesalamine) rarely induces hyper- sensitivity reactions. If chest pain associated with atypical electrocardiographic changes are seen during its administration, one should always bear in mind type I variant of Kounis syndrome. This variant includes patients, of any age, with normal coronary arteries, without predisposing factors for coronary artery disease, in whom the acute release of inflammatory mediators from mast cells can induce either sudden coronary artery narrowing, without increase of cardiac enzymes and troponins, or coronary artery spasm that progresses to acute myocardial infarction, with elevated cardiac enzymes and troponins. 展开更多
关键词 Drug hypersensitivity Kounis syndrome MESALAMINE SALICYLATES
下载PDF
上一页 1 2 8 下一页 到第
使用帮助 返回顶部