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小麦分离合子与幼胚中膜钙和钙调素的分布 被引量:14
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作者 赵洁 周嫦 杨弘远 《Acta Botanica Sinica》 CSCD 1998年第1期28-32,共5页
用非酶手工显微解剖法分离小麦(TriticumaestivumL.)合子与幼胚。应用金霉素(CTC)和氟奋乃静(FPZ)荧光探针,观察了合子与胚胎发育过程中膜钙和活化钙调素的分布。合子原生质体CTC荧光呈极性分布。二... 用非酶手工显微解剖法分离小麦(TriticumaestivumL.)合子与幼胚。应用金霉素(CTC)和氟奋乃静(FPZ)荧光探针,观察了合子与胚胎发育过程中膜钙和活化钙调素的分布。合子原生质体CTC荧光呈极性分布。二细胞至十几个细胞原胚时期各细胞间的CTC和FPZ荧光均匀分布。幼小梨形胚胚体CTC和FPZ荧光稍强于胚柄。接近分化的梨形胚CTC荧光仅位于胚体与胚柄之间的几层细胞和胚体腹侧中部的几个细胞中。胚芽刚分化时,胚基部CTC荧光较强,FPZ荧光则仅出现在胚基部。讨论了合子分离技术和膜钙与钙调素(CaM)在胚胎发育中的可能作用。 展开更多
关键词 分离合子 胚胎发育 膜钙 钙调素 小麦
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A method for calculation of ion distribution in reaction system forming hydroxide
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作者 金哲男 郑大录 +3 位作者 洪正秀 郑英勋 路殿坤 陈国宝 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第12期3793-3798,共6页
A formula was proposed to calculate the distribution of metal ions quantitatively in chemical reaction system forming hydroxide where precipitation and complex are formed together. The effects of some factors on forma... A formula was proposed to calculate the distribution of metal ions quantitatively in chemical reaction system forming hydroxide where precipitation and complex are formed together. The effects of some factors on formation of precipitation and complex were investigated, and the corresponding precipitation rates of zinc, iron (III), aluminum, copper and magnesium were calculated. As a result, it shows that the proposed formula is reliable. By the proposed formula, the existence state of metal ions in hydroxides reaction system with any metal ions can be well described and the effects of some factors on the distribution of metal ions were determined. 展开更多
关键词 HYDROXIDE metal ions distribution precipitation rate complex forming rate
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Spectral Differences of the Molecule-ion Adducts of β-Cyclodextrin and Lithium Carbonate 被引量:2
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作者 柏雷 宋乐新 +1 位作者 王莽 朱林红 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2010年第1期117-124,I0002,共9页
A small shielding effect on the hydrogen atoms of chiral carbons of β-cyclodextrin (β-CD) was detected by 1H nuclear magnetic resonance, but a large environmental change of the chiral carbon atoms at high concentr... A small shielding effect on the hydrogen atoms of chiral carbons of β-cyclodextrin (β-CD) was detected by 1H nuclear magnetic resonance, but a large environmental change of the chiral carbon atoms at high concentration ratios of lithium carbonate (Li2CO3) to β-CD was observed by polarimetry in aqueous solution. These findings urged us to investigate whether different formation conditions of the molecule-ion system between Li2CO3 and β-CD in solid state were involved in different spectral performances. To answer the question, we prepared three adducts of Li2CO3 to β-CD, i.e., samples 1, 2, and 3, by magnetic stirring, solvothermal and grinding conditions, respectively. Powder X-ray diffraction and Fourier transformation infrared spectroscopy provided the information of formation of the three molecule-ion adducts. Besides, scanning electron microscope images provided different surface information of the three adducts. Further, significant spectral differences in thermal behavior of these adducts were found by thermogravimetry and derivative thermogravimetry. 展开更多
关键词 Β-CYCLODEXTRIN Li2CO3 Molecule-ion interaction ADDUCT
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Rare Earth Metals Ion-exchanged β-Zeolites as Supports of Platinum Catalysts for Hydroisomerization of n-Heptane 被引量:6
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作者 刘平 姚月 +1 位作者 张兴光 王军 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2011年第2期278-284,共7页
A series of Pt catalysts supported on the Hβ-zeolite that is ion-exchanged with the rare earth metal ions of Ce(III) and La(III),are prepared by impregnation,characterized by inductively coupled plasma (ICP),X-... A series of Pt catalysts supported on the Hβ-zeolite that is ion-exchanged with the rare earth metal ions of Ce(III) and La(III),are prepared by impregnation,characterized by inductively coupled plasma (ICP),X-ray diffraction (XRD),BET,temperature-programmed desorption of ammonia (NH3-TPD),temperature-programmed reduction of hydrogen (H2-TPR) and H2-chemisorption techniques,and evaluated in the hydroisomerization of n-heptane with an atmospheric fixed-bed reactor.The reaction temperature,time on stream,space velocity,and the ratio of H2/n-heptane are changed to get the optimal conditions.The Ce(III) and La(III)-exchanged Hβ-zeolites exhibit higher selectivity for isomerized products than the neat Hβ-zeolite.Moreover,the Ce(III)-exchanged catalysts give higher conversions of n-heptane,whereas the La(III)-exchanged ones do not show any improvement in con-version.Under optimal conditions,the catalyst with 0.4% (by mass) Pt and 0.5% (by mass) Ce loading presents very high selectivity of isomerized products of 95.1% coupled with high n-heptane conversion of 68.7%.Effects of the ion-exchange of Ce(III) and La(III) on the catalytic performance are discussed in relation with the physico-chemical properties of catalysts. 展开更多
关键词 hydroisomerization of n-heptane β-zeolite bifunctional catalyst CE LA
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Organotemplate-free Hydrothermal Synthesis of SUZ-4 Zeolite: Influence of Synthesis Conditions 被引量:1
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作者 周华兰 吴雅静 +1 位作者 张伟 王军 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2014年第1期120-126,共7页
Various conditions were investigated in detail for the novel organic template-free static hydrothermal synthesis of SUZ-4 zeolite in the presence of seeds. The obtained samples were characterized by XRD (X-ray diffra... Various conditions were investigated in detail for the novel organic template-free static hydrothermal synthesis of SUZ-4 zeolite in the presence of seeds. The obtained samples were characterized by XRD (X-ray diffraction), SEM (scanning electron microscope), TG (thermal gravimetric analysis), ICP (inductively coupling plasma) elemental analysis, nitrogen sorption isotherm and surface area. The results show that pure SUZ-4 zeolites with high crystallinity are obtained in a broad window of synthesis conditions: seed mass concentration 0.2%-2%, SIO2/A1203 molar ratio 21 25, KOH/SiO2 molar ratio 0.33 0.43, H20/SiO2 molar ratio 7.14-38.1, aging time 24 h, crystallization temperature 160℃, and crystallization time 6-10 d. Also, crystallinity and size of the rod-like SUZ-4 zeolite crystals are found to alter with the conditions. 展开更多
关键词 crystal growth microporous materials SUZ-4 zeolite zeolite synthesis organic template-free
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Theoretical research on vacuum separation of Au-Ag alloy 被引量:3
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作者 Shuang-ping WANG Jin-yang ZHAO +3 位作者 Bao-qiang XU Ling-xin KONG Wen-long JIANG Bin YANG 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2022年第8期2719-2726,共8页
To provide an accurate prediction of the product component dependence of temperature and pressure in vacuum distillation and give convenient and efficient guidance for the designing of the process parameters of indust... To provide an accurate prediction of the product component dependence of temperature and pressure in vacuum distillation and give convenient and efficient guidance for the designing of the process parameters of industrial production, according to the molecular interaction volume model(MIVM), the separation coefficient(β) and vapor-liquid equilibrium composition of Au-Ag alloy at different temperatures are calculated. Combined with the vapor-liquid equilibrium(VLE) theory, the VLE phase diagrams, including the temperature-composition(T-x) and pressure-composition(p-x) diagrams of Au-Ag alloy in vacuum distillation are plotted. The triple points and condensation temperatures of gold and silver vapors are calculated as well. The results show that the β decreases and the contents of gold in vapor phase increase with the distillation temperature increasing. Low pressures have positive effect on the separation of Ag and Au. The difference between the condensation temperatures of gold and silver is about 450 K in the pressure range of 1-10 Pa. 展开更多
关键词 Au-Ag alloy vacuum separation molecular interaction volume model(MIVM) vapor-liquid equilibrium(VLE)phase diagram condensation temperature
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Probing Molecular Interactions in 1-Butyl-3-methylimidazolium Chloride-Water and 2,6-Dimethoxyphenol Mixtures Using Attenuated Total Reflection Infrared Spectroscopy 被引量:1
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作者 王艳涛 李坤兰 +1 位作者 魏立纲 马英冲 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2017年第5期521-528,I0001,共9页
Molecular interactions of the ternary mixtures of 1-butyl-3-methylimidazolium chloride ([C4C1im]Cl)-water-2,6-dimethoxyphenol (2,6-DMP, a phenolic monomer lignin model compound) were investigated in comparison wit... Molecular interactions of the ternary mixtures of 1-butyl-3-methylimidazolium chloride ([C4C1im]Cl)-water-2,6-dimethoxyphenol (2,6-DMP, a phenolic monomer lignin model compound) were investigated in comparison with the [C4C1im]Cl-water binary systems through attenuated total reflection infrared spectroscopy. Results indicated that the microstructures of water and [C4C1im]Cl changed with varying mole fraction of [C4C1im]Cl (xIL) from 0.01 to 1.0. This change was mainly attributed to the interactions of [C4C1im]Cl-water and the self-aggregation of [C4C1im]Cl through hydrogen bonding. The band shifts of C-H on imidazolium ring and the functional groups in 2,6-DMP indicated that the occurrence of intermolecular interactions by different mechanisms (i.e., hydrogen bonding or π-π stacking) resulted in 2,6-DMP dissolution. In the case of xIL=0.12, the slightly hydrogen-bonded water was fully destroyed and [C4C1im]Cl existed in the form of hydrated ion pairs. Interestingly, the maximum 2,6-DMP solubility (238.5 g/100 g) was achieved in this case. The interactions and microstructures of [C4C1im]Cl-water mixtures influenced the dissolution behavior of 2,6-DMP. 展开更多
关键词 Lignin model compound Ionic liquid-water Molecular interactions
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Upper Triangular Matrix of Lie Algebra and a New Discrete Integrable Coupling System
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作者 YU Fa-Jun ZHANG Hong-Qing 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第3期393-396,共4页
The upper triangular matrix of Lie algebra is used to construct integrable couplings of discrete solition equations. Correspondingly, a feasible way to construct integrable couplings is presented. A nonlinear lattice ... The upper triangular matrix of Lie algebra is used to construct integrable couplings of discrete solition equations. Correspondingly, a feasible way to construct integrable couplings is presented. A nonlinear lattice soliton equation spectral problem is obtained and leads to a novel hierarchy of the nonlinear lattice equation hierarchy. It indicates that the study of integrable couplings using upper triangular matrix of Lie algebra is an important step towards constructing integrable systems. 展开更多
关键词 upper triangular matrix Lie algebra integrable coupling system
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Enhancing Effect of Fe^(2+) on the Formaldehyde Production from Trimethylamine N-oxide Decomposition Catalyzed by the Extract of Harpadon nehereus Kidney 被引量:2
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作者 SUN Yong ZHOU Deqing ZHAO Feng 《Journal of Ocean University of China》 SCIE CAS 2011年第1期67-72,共6页
The effects of Fe2+ on the trimethylamine N-oxide (TMAO) demethylating activity of the Harpadon nehereus kidney extract were studied in this research.The activity of the kidney extract was presumably inhibited by ethy... The effects of Fe2+ on the trimethylamine N-oxide (TMAO) demethylating activity of the Harpadon nehereus kidney extract were studied in this research.The activity of the kidney extract was presumably inhibited by ethylene diamine tetra-acetic acid (EDTA),which indicates that the kidney extract contains an enzyme or enzyme system with metal cations as activator.Activity of the kidney extract was enhanced significantly when Fe2+ was added into the model system in vitro.As the concentration of Fe2+ increased,the decomposing rate of TMAO increased rapidly until TMAO decomposed completely.The activity of the kidney extract was also enhanced by reductant such as ascorbic acid.Inductively Coupled Plasma-Atomic Emission Spectrometry (ICP-AES) was employed to determine the content of total iron in a number of fishery products.Significant positive correlation between the contents of total iron and endogenous formaldehyde (FA) was found,especially in marine products. 展开更多
关键词 TMAOase FORMALDEHYDE mechanism Fe2+ Harpadon nehereus
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Robust Scheme for Long-Distance Teleportation of an Unknown Atomic State
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作者 ZHENG Shi-Biao 《Communications in Theoretical Physics》 SCIE CAS CSCD 2006年第3期429-432,共4页
A scheme is presented for the long-distance teleportation of an unknown atomic state between two separated cavities. The scheme is based on the Raman coupling and cavity decay. In the scheme, the effective atom-cavity... A scheme is presented for the long-distance teleportation of an unknown atomic state between two separated cavities. The scheme is based on the Raman coupling and cavity decay. In the scheme, the effective atom-cavity coupling strength is much smaller than the cavity decay rate and thus cavities of high quality factor are unnecesssary. 展开更多
关键词 TELEPORTATION atomic state Raman coupling
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Molecular Simulation of CO2/H2 Mixture Separation in Metal-organic Frameworks: Effect of Catenation and Electrostatic Interactions 被引量:3
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作者 阳庆元 许青 +2 位作者 刘蓓 仲崇立 Smit Berend 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2009年第5期781-790,共10页
In this work grand canonical Monte Carlo simulations were performed to study gas separation in three pairs of isoreticular metal-organic frameworks (IRMOFs) with and without catenation at room temperature.Mixture comp... In this work grand canonical Monte Carlo simulations were performed to study gas separation in three pairs of isoreticular metal-organic frameworks (IRMOFs) with and without catenation at room temperature.Mixture composed of CO2 and H2 was selected as the model system to separate.The results show that CO2 selectivity in catenated MOFs with multi-porous frameworks is much higher than their non-catenated counterparts.The simulations also show that the electrostatic interactions are very important for the selectivity,and the contributions of different electrostatic interactions are different,depending on pore size,pressure and mixture composition.In fact,changing the electrostatic interactions can even qualitatively change the adsorption behavior.A general conclusion is that the electrostatic interactions between adsorbate molecules and the framework atoms play a dominant role at low pressures,and these interactions in catenated MOFs have much more pronounced effects than those in their non-catenated counterparts,while the electrostatic interactions between adsorbate molecules become evident with increasing pressure,and eventually dominant. 展开更多
关键词 SEPARATION CATENATION electrostatic interactions metal-organic frameworks molecular simulation
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Isolation of Main Genes Involved in Flowering of Saffron (Crocus sativus L.) in Order to Study Effective Flowering Protein
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作者 Iman Yousefi Javan Yousef Hosseinzadehgonabad 《Journal of Food Science and Engineering》 2017年第8期396-399,共4页
Saffron (Crocus sativus L.) always is grown for using its flowers in nutrient industry, color industry and healthy compounds due to its flowers and specially stigmas. Because of its expensive flowers, surveying and ... Saffron (Crocus sativus L.) always is grown for using its flowers in nutrient industry, color industry and healthy compounds due to its flowers and specially stigmas. Because of its expensive flowers, surveying and recognizing on effective genes for flowering is very important and its results can help us to control rate and timing of flowering at an early stage of flowering. The gene and gene state meant Pistillata like MADS box (PIC2) were surveyed for recognizing its molecular mechanism. The molecular sequence at the genes has high similarity to members of family MADS that is a factor for controls of protein at flowering stage. PIC2 gene was studied by bioinforrnatics resources. Primers were designed for replicating the gene and DNA and RNA were extracted from saffron's leaves. The gene's eDNA was built by recopying enzyme and used such a pattern for replicating gene PIC2 at polymerase chain reactions (PCR). Segments were replicated such 900 eDNA pair-nucleotides and a segment such 2,100 of DNA's pair-nucleotides. The gene codes a protein that was composed of 210 amino acids that has MADS sequence box. Analysis of protein's molecular structure and homological modeling of the protein indicated that it has a regular structure. 展开更多
关键词 SAFFRON PIC2 gene MADS sequence box gene state homological modeling.
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Application of NaHCO_3/ DTPA Extractant-ICP Spectrometry Technique in Soil Test for Availability of Nutrients and Heavy Metals 被引量:4
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作者 CHEN TONG-BINBeifng Agroecosystem Experimental Station, Institute of Geography, Chinese Academy of Sciences, Beifng 100101 (China) 《Pedosphere》 SCIE CAS CSCD 1993年第4期377-382,共6页
Soil test for availability of nutrients and heavy metals is extensively served as a means for the evaluations of soil fertility, and environmental effects and phytotoxicity of pollutants in soils, and for the fertiliz... Soil test for availability of nutrients and heavy metals is extensively served as a means for the evaluations of soil fertility, and environmental effects and phytotoxicity of pollutants in soils, and for the fertilizer recommendation in agricultural and environmental sciences. Therefore, great attention has been paid to the measurement of elemental availability in soil test. 展开更多
关键词 calcareous soil elemental availability ICP spectrometry NaHCO3/ DTPA extractant soil test
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Design of Fe (Ⅲ) and Hg (Ⅱ) Ion Selective Electrodes
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作者 Tuncer Mutlu 《Journal of Chemistry and Chemical Engineering》 2011年第5期451-455,共5页
Principally the basis of ISE is selecting of a support solid matrix and a nonsoluble compound or complexes of insighted cation, mixed with this solid. For preparing the ISE membranes there are some materials such PVC,... Principally the basis of ISE is selecting of a support solid matrix and a nonsoluble compound or complexes of insighted cation, mixed with this solid. For preparing the ISE membranes there are some materials such PVC, PE, organic polyelectrolytes, conducting polymers and inorganic compounds. The black white microscope photos are included, too. Detailed schemes and pictures of the electrodes and correlations were shown in the following article. Results are seen compatible for construction of the versatile ISE electrodes. 展开更多
关键词 ISE electrode SCE ADHESIVE polymer MW pH and mV calibrations.
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Construction of a chimeric hepatitis C virus replicon based on a strain isolated from a chronic hepatitis C patient 被引量:1
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作者 Huang Cao Wandi Zhu +2 位作者 Qingxia Han Rongjuan Pei Xinwen Chen 《Virologica Sinica》 SCIE CAS CSCD 2014年第1期61-70,共10页
Subgenomic replicons of hepatitis C virus (HCV) have been widely used for studying HCV replication.Here,we report a new subgenomic replicon based on a strain isolated from a chronically infected patient.The coding s... Subgenomic replicons of hepatitis C virus (HCV) have been widely used for studying HCV replication.Here,we report a new subgenomic replicon based on a strain isolated from a chronically infected patient.The coding sequence of HCV was recovered from a Chinese chronic hepatitis C patient displaying high serum HCV copy numbers.A consensus sequence designated as CCH strain was constructed based on the sequences of five clones and this was classified by sequence alignment as belonging to genotype 2a.The subgenomic replicon of CCH was replication-deficient in cell culture,due to dysfunctions in NS3 and NS5B.Various JFH1/CCH chimeric replicons were constructed,and specific mutations were introduced.The introduction of mutations could partially restore the replication of chimeric replicons.A replication-competent chimeric construct was finally obtained by the introduction of NS3 from JFH1 into the backbone of the CCH strain. 展开更多
关键词 hepatitis C virus subgenomic replicon MUTATION
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Chemical Composition and Mechanical Characteristic of Nitrogen Ion Beam Mixed Carbon Nanolayer
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作者 Frantisek Cemy Petr Vlcak +3 位作者 Janez Kovac Josef Sepitka Martin Klima Libor Dvorak 《Journal of Chemistry and Chemical Engineering》 2014年第5期488-492,共5页
Ion beam methods for modification of nanohardness of surface nanolayers of the titanium alloy Ti6AI4V were applied. After deposition of carbon nanolayers by electron beam evaporation, the ion implantation of nitrogen ... Ion beam methods for modification of nanohardness of surface nanolayers of the titanium alloy Ti6AI4V were applied. After deposition of carbon nanolayers by electron beam evaporation, the ion implantation of nitrogen into samples was carried out. The chemical composition of the modified surface area was investigated by AES (auger electron spectroscopy). The nanohardness of resulted ion beam modified surface nanolayers were investigated by nanoindentation testing. The measured concentration profiles indicate the atomic mixing of carbon into the substrate. It was found that the modified samples had a markedly higher nanohardness than the unmodified samples. The increased nanohardness is attributed to the newly created phases in the surface area. 展开更多
关键词 NANOCOMPOSITE carbon thin film electron beam evaporation ion implantation.
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Aromaticity of Heterofullerenes C18BxNy (x+y=2) and Their Molecular lons
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作者 Jia-li Chen Ablikim Kerim 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 北大核心 2008年第2期118-122,共5页
The aromaticity of all possible substituted fullerene isomers of C18N2, C18B2, C18BN, and their molecular ions which originate from the C20 (Ih) cage were studied by the topological resonance energy (TRE) and the ... The aromaticity of all possible substituted fullerene isomers of C18N2, C18B2, C18BN, and their molecular ions which originate from the C20 (Ih) cage were studied by the topological resonance energy (TRE) and the percentage topological resonance energy methods. The relationship between the aromaticity of C18BxNy isomers and the sites where the heteroatoms dope at the C20 (Ih) cage is discussed. Calculation results show that at the neutral and cationic states all the isomers are predicted to be antiaromatic with negative TREs, but their polyvalent anions are predicted to be aromatic with positive TREs. The most stable isomer is formed by heteroatom doping at the 1,11-sites in C18N2. C18B2, and C18BN. Heterofullerenes are more aromatic than C20. The stability order in the neutral states is C18N2〉C18BN〉C18B2〉C20. The stability order in closed-shell is C18B2^8- 〉C20^6- 〉C18BN^6- 〉C18N2^4-. This predicts theoretically that their polyvalent anions have high aromaticity. 展开更多
关键词 C18N2 C18B2 C18BN Aromaticity Topological resonance energy
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Mineral Constituents in Common Chanterelles and Soils Collected from a High Mountain and Lowland Sites in Poland 被引量:1
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作者 Jerzy FALANDYSZ MaIgorzata DREWNOWSKA +2 位作者 Grayna JARZYNSKA ZHANG Dan WANG Jipeng 《Journal of Mountain Science》 SCIE CSCD 2012年第5期697-705,共9页
This paper reported the results of the determination of Ag, A1, Ba, Ca, Cd, Co, Cr, Cu, Fe, K, Mg, Mn, Na, Ni, P, Pb, Rb, Sr and Zn in Common Chanterelles (Cantharellus cibarius) Fr. and surface soil layer (o-io cm... This paper reported the results of the determination of Ag, A1, Ba, Ca, Cd, Co, Cr, Cu, Fe, K, Mg, Mn, Na, Ni, P, Pb, Rb, Sr and Zn in Common Chanterelles (Cantharellus cibarius) Fr. and surface soil layer (o-io cm) underneath the fruiting bodies. Mushrooms and soils were collected from a lowland site in the Hel Peninsula (Baltic Sea coast) and a high mountain site in the Tatra Mountains. The trace elements were determined using validated method and inductively coupled plasma - atomic emission spectroscopy (ICP-AES). Common Chanterelles that emerged at sites poor in mineral nutrients podzols of the Hel Peninsula forests efficiently bioeoncentrated several essential trace elements (K, P, Co, Cu, Mn, Na, Zn), while the abundance of those elements in carpophores was around half less compared to specimens from Zakopane region and which emerged in soils much richer in minerals. Common Chanterelles collected at two spatially distant background areas in Poland were only weakly contaminated with metals such as Ag, Cd, Hg and Pb. The maximum tolerable Cd and Pb contents of certain cultivated mushrooms are regulated in the European Union by law and these hazardous metals in C. cibarius were far below tolerance limits set. 展开更多
关键词 Common Chanterelles Trace elements Fruiting bodies Bioconcentration factor
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Preparation and adsorption behaviors of Cu(Ⅱ) ion-imprinted polymers
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作者 钟世安 《Journal of Chongqing University》 CAS 2008年第1期23-27,共5页
Imprinted polymers were prepared for selective removal of Cu(Ⅱ) ions from metal solutions. Three ion-imprinted polymers were synthesized with methacrylic acid (MAA), acrylamide (AA) and N,N'-methylenebisacryla... Imprinted polymers were prepared for selective removal of Cu(Ⅱ) ions from metal solutions. Three ion-imprinted polymers were synthesized with methacrylic acid (MAA), acrylamide (AA) and N,N'-methylenebisacrylamide (MBAA) respectively as the functional monomers, ethleneglycoldimethacrylate (EGDMA) as the cross-linking agent, 2,2'- azobisisobutyronitrile (AIBN) as the initiator and Cu (Ⅱ) ion as the imprint ion. The template Cu (Ⅱ) ion was removed from the polymer by leaching with a liquid of a 1:1 volumetric ratio of HCl to ethylenediaminetetraacetic acid (EDTA). The capacity and selectivity of Cu(Ⅱ) ion adsorption were investigated with the three imprinted polymers and their non-imprinted counterparts. The polymers have a maximum adsorption capacity at pH 7.0. The isotherm of their batch adsorption of Cu(Ⅱ) ions shows a Langmuir adsorption pattern. Imprinted polymers all have a much higher capacity and higher selectivity of Cu(Ⅱ) adsorption than nonimprinted ones. MAA polymer benefits the most from imprinting. Imprinted MAA polymer has the highest selectivity when used to rebind Cu (Ⅱ) ion from an aqueous solution in the presence of other metal ions. Ion imprinting can be a promising technique of preparing selective adsorbents to separate and preconcentrate metal in a medium of multiple competitive metal ions through solid phase extraction (SPE). 展开更多
关键词 molecular recognition COMPLEXATION metal ion imprinted polymer PRECONCENTRATION solid phase extraction atomic absorption spectrometry copper ion selective adsorption
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Selective recovery of Cu(Ⅱ) through polymer inclusion membranes mediated with 2-aminomethylpyridine derivatives
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作者 Xue-jing QIU Jia TANG +3 位作者 Jun TAN Hui-ping HU Xiao-bo JI Jiu-gang HU 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2021年第11期3591-3601,共11页
The Cu(Ⅱ) separation behaviors with polymer inclusion membranes(PIMs) are explored by modifying 2-aminomethylpyridine derivatives with hydrophobic alkyl chains, including 2-[N-(tert-butyloxycarbonylmethyl)-2-picolyam... The Cu(Ⅱ) separation behaviors with polymer inclusion membranes(PIMs) are explored by modifying 2-aminomethylpyridine derivatives with hydrophobic alkyl chains, including 2-[N-(tert-butyloxycarbonylmethyl)-2-picolyamino]acetate(AMB), N,N-dioctyl-2-aminomethylpyridine(AMD), tert-butyl 2-(N-octyl-2-picolyamino) acetate(AMC), and N,N-didecyl-2-aminomethylpyridine(AME). The transport flux and selectivity of Cu(Ⅱ) are determined by optimizing composition and structure of carriers and plasticizers. The results show that the hydrophobic modification of 2-aminomethylpyridine derivatives can boost the selective transport of copper ions in PIMs and membrane stability. In the optimum composition of 30 wt.% PVC, 30 wt.% AME, and 40 wt.% NPOE, the initial flux of Cu(Ⅱ) is 5.8×10^(−6) mol·m^(−2)·s^(−1). The FT-IR and XPS spectra identify that the alkyl amine functional groups of AME involve in the transport of copper chloride species. The SAXS analysis demonstrates that the generated micro-channels in PIMs induced by the hydrophobic modification of 2-aminomethylpyridine derivatives can contribute to the enhanced Cu(Ⅱ) flux. 展开更多
关键词 hydrophobic modification 2-aminomethylpyridine derivative polymer inclusion membrane Cu(Ⅱ) separation
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