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浅析中医人文精神与社会主义核心价值观培育合位性教育模式构建 被引量:1
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作者 唐雪梅 吴娟 胡迪 《成都中医药大学学报(教育科学版)》 2017年第3期4-5,18,共3页
兼具中医人文精神和社会主义核心价值观是成为合格中医药人才的首要素质条件。本文旨在分析中医人文精神与社会主义核心价值观在方向性、涵盖性、认同性和目标性方面的高度契合,找准两者之间的相同点、相融点和互促点,探索建立赋有中医... 兼具中医人文精神和社会主义核心价值观是成为合格中医药人才的首要素质条件。本文旨在分析中医人文精神与社会主义核心价值观在方向性、涵盖性、认同性和目标性方面的高度契合,找准两者之间的相同点、相融点和互促点,探索建立赋有中医药文化特色的社会主义核心价值观融合教育模式,以期实现中医药院校大学生践行社会主义核心价值观的认同根植目标。 展开更多
关键词 中医人文精神 社会主义核心价值观 合位性
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Syntheses and catalytic performances of three coordination polymers with tetracarboxylate ligands
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作者 MEI Zhenzhong WANG Hongyu +2 位作者 KANG Xiuqi SHAO Yongliang GU Jinzhong 《无机化学学报》 SCIE CAS CSCD 北大核心 2024年第9期1795-1802,共8页
Three zincand cobaltcoordination polymers,namely{[Zn_(2)(μ_(6)-adip)(phen)_(2)]·4H_(2)O}_(n)(1),{[Co_(2)(μ_(6)-adip)(bipy)_(2)]·4H_(2)O}_(n)(2),and[Co_(2)(μ4-adip)(μ-bpa)_(2)]_(n)(3)have been constructed... Three zincand cobaltcoordination polymers,namely{[Zn_(2)(μ_(6)-adip)(phen)_(2)]·4H_(2)O}_(n)(1),{[Co_(2)(μ_(6)-adip)(bipy)_(2)]·4H_(2)O}_(n)(2),and[Co_(2)(μ4-adip)(μ-bpa)_(2)]_(n)(3)have been constructed hydrothermally using H4adip(H4adip=5,5′-azanediyldiisophthalic acid),phen(phen=1,10-phenanthroline),bipy(bipy=2,2′-bipyridine),bpa(bpa=bis(4-pyridyl)amine),and zinc and cobalt chlorides at 160℃.The products were isolated as stable crystalline solids and were characterized by IR spectra,elemental analyses,thermogravimetric analyses,and single-crystal X-ray diffrac-tion analyses.Single-crystal X-ray diffraction analyses revealed that three compounds crystallize in the orthorhom-bic system Pnna(1 and 2)or P21212(3)space groups.All compounds exhibit 3D frameworks.The catalytic perfor-mances in the Henry reaction of these compounds were investigated.Compound 3 exhibited an effective catalytic activity in the Henry reaction at 70℃.CCDC:2339391,1;2339392,2;2339393,3. 展开更多
关键词 coordination polymer tetracarboxylic acid catalytic properties Henry reaction
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Syntheses,crystal structures,and catalytic properties of three zinc(Ⅱ),cobalt(Ⅱ)and nickel(Ⅱ)coordination polymers constructed from 5⁃(4⁃carboxyphenoxy)nicotinic acid
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作者 LING Weizhong CHEN Xiangyun +2 位作者 LIU Wenjing HUANG Yingkai LI Yu 《无机化学学报》 SCIE CAS CSCD 北大核心 2024年第9期1803-1810,共8页
Three zinc(Ⅱ),cobalt(Ⅱ),and nickel(Ⅱ)coordination polymers,namely[Zn(μ^(3-)cpna)(μ-dpea)_(0.5)]_(n)(1),[Co(μ^(3-)cpna)(μ-dpey)_(0.5)]_(n)(2),and[Ni(μ^(3-)cpna)(μ-dpey)_(0.5)(H_(2)O)]_(n)(3),have been construc... Three zinc(Ⅱ),cobalt(Ⅱ),and nickel(Ⅱ)coordination polymers,namely[Zn(μ^(3-)cpna)(μ-dpea)_(0.5)]_(n)(1),[Co(μ^(3-)cpna)(μ-dpey)_(0.5)]_(n)(2),and[Ni(μ^(3-)cpna)(μ-dpey)_(0.5)(H_(2)O)]_(n)(3),have been constructed hydrothermally using H_(2)cpna(5-(4-carboxyphenoxy)nicotinic acid),dpea(1,2-di(4-pyridyl)ethane),dpey(1,2-di(4-pyridyl)ethylene),and zinc,cobalt,and nickel chlorides at 160℃.The products were isolated as stable crystalline solids and were characterized by IR spectra,elemental analyses,thermogravimetric analyses,and single-crystal X-ray diffraction analyses.Single-crystal X-ray diffraction analyses revealed that three compounds crystallize in the triclinic system,space group P1.Compounds 1-3 show 2D layer structures.The catalytic activities in the Knoevenagel condensation reaction of these compounds were investigated.Compounds 1 and 2 exhibit effective catalytic activities in the Knoevenagel condensa-tion reaction at room temperature.For this reaction,various parameters were optimized,followed by the investiga-tion of the substrate scope.CCDC:2335676,1;2335677,2;2335678,3. 展开更多
关键词 coordination polymer dicarboxylic acid catalytic property Knoevenagel condensation reaction
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Effect of electropulsing on dislocation mobility of titanium sheet 被引量:5
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作者 宋辉 王忠金 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2012年第7期1599-1605,共7页
To investigate the effect of the electropulsing on dislocation mobility,specimens cut from the cold-rolled titanium sheet were treated by high density electropulsing with the maximum current density of 7.22,7.64,7.96 ... To investigate the effect of the electropulsing on dislocation mobility,specimens cut from the cold-rolled titanium sheet were treated by high density electropulsing with the maximum current density of 7.22,7.64,7.96 kA/mm 2 ,pulse period 110μs.The internal friction and elastic modulus were measured by a dynamic mechanical analyzer(DMA).When strain amplitude lowers a certain critical one,the damping of the electropulsed titanium sheet is lower than that of the cold-rolled one.When the strain amplitude exceeds the critical one,the damping of the electropulsed titanium sheet is extraordinarily higher than that of the cold-rolled or conventional annealed one.Furthermore,it is found that the damping peak of the electropulsed titanium sheet shifts to lower temperature compared with the conventional annealed one.It is demonstrated that the electropulsing treatment can decrease dislocation tangles and enhance dislocation mobility. 展开更多
关键词 titanium alloys dislocation mobility DAMPING ELECTROPULSING
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Enhancement of Rice Germplasm by Pyramiding the Cultivars with Multi-resistance to Orseolia oryzae (Wood-Mason) 被引量:2
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作者 冯锐 秦学毅 +5 位作者 唐建淮 朱汝财 潘英华 刘百龙 韦素美 黄凤宽 《Agricultural Science & Technology》 CAS 2009年第1期7-10,共4页
[ Objective] This study was to breed rice cultivars with multi-resistance to Orseolia oryzae (Wood-Mason). [ Method] The Guangxi local cultivar GX-M001 (Jiangchao) with high resistance to Orseolia oryzae (Wood-Ma... [ Objective] This study was to breed rice cultivars with multi-resistance to Orseolia oryzae (Wood-Mason). [ Method] The Guangxi local cultivar GX-M001 (Jiangchao) with high resistance to Orseolia oryzae (Wood-Mason) was used to hybrid with the known resistance cultivars "Kangwenqingzhan" (harboring GM5 gene), OB677( harboring GM3 gene) from Sri Lanka, HT1350 and high yield end quality cultivar " Guiruanzhan". [ Result] Through pyramiding the multi-resistant genes via routine hybridization, the general resistances of the hybrids were remarkably enhanced. The grades of resistance were also improved, many of the combinations were endowed with a resistance at immune level (grade 0) ; and interestingly, the respective hybridization of GX-M001 (high resistance) with OB677( medium resistance) and HT1350(suscepti- ble) also generate two lines at immune level, which is probably the effects of additive effects of genes.[ Conclusion] By routine hybridization, multiple genes were successfully pyramided, thus generating novel rice lines with multiple resistances. For the rice breeding scientists at the grass-roots level, the resistance-resistance pyramiding is an effective approach to breed high resistance cultivars. 展开更多
关键词 Orseolia oryzae (Wood-Mason) Pyramiding via hybridization Rice breeding
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Synthesis,crystal structure and adsorption properties of a novel Fe(Ⅲ) porous coordination polymer containing 1,4-naphthalenedicarboxylate ligand 被引量:1
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作者 陈金喜 孟伟伟 张若冰 《Journal of Southeast University(English Edition)》 EI CAS 2011年第1期107-110,共4页
A novel porous coordination polymer,iron naphthalenedicarboxylate Fe(OH)(1,4-NDC)·2H2O is hydrothermally synthesized by the reaction of FeSO4·7H2O and 1,4-naphthalenedicarboxylic acid(1,4-H2NDC) at 150... A novel porous coordination polymer,iron naphthalenedicarboxylate Fe(OH)(1,4-NDC)·2H2O is hydrothermally synthesized by the reaction of FeSO4·7H2O and 1,4-naphthalenedicarboxylic acid(1,4-H2NDC) at 150℃.The compound crystallizes in a tetragonal space group P42/nmc:a=2.1447(4) nm,c=0.68849(14) nm,V=3.1669(11) nm3,Z=8,R=0.0845,wR=0.1829.The crystal structure exhibits a three-dimensional framework which is composed of infinite chains of corner-sharing octahedral Fe(OH)2O4 with 1,4-NDC ligands forming two types of channels with square-shaped cross-sections.The large channels present a cross-section of 0.76 nm×0.76 nm,while the small channels are about 0.30 nm×0.30 nm.No structural transformation occurs after removing the guest water molecules,while a robust structure generates with permanent porosity.The adsorption measurements show that the anhydrous sample of the compound can adsorb CO2 into its pores.The adsorption isotherms for methanol,acetone,tetrahydrofuran and benzene are also measured. 展开更多
关键词 porous coordination polymer selective adsorption 1 4-naphthalenedicarboxylic acid
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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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In-situ synthesis of Al_3Ti particles reinforced Al-based composite coating
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作者 牛立斌 张菊梅 杨小兰 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2012年第6期1387-1392,共6页
Using titanium wires (99.5%, 200 μm in diameter) as a reactive source, an Al-based composite coating reinforced by titanium tri-aluminide (A13Ti) particles was fabricated by infiltration plus in-situ methods. Acc... Using titanium wires (99.5%, 200 μm in diameter) as a reactive source, an Al-based composite coating reinforced by titanium tri-aluminide (A13Ti) particles was fabricated by infiltration plus in-situ methods. According to the differential thermal analysis (DTA) curve, the reactive temperature between Ti wires and A1 matrix can be determined at 890 ℃. The obtained composite coatings were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and microhardness and wear test. The experimental results show that when holding period is 20 min at 890℃, the titanium wires react completely to in-situ synthesize Al3Ti particles, which presents blocky and strip-like states. The microhardness of in-situ synthesized Al3Ti particles is about 4.5 times that of the Al-matrix. Under the condition of dry sliding at 10 N load, compared with the unreinforced Al matrix, the composite coating fabricated with 20 min offers unique wear resistance behavior, and its wear mechanism is that the adhesive wear and abrasive wear coexist. 展开更多
关键词 INTERMETALLICS in-situ reaction composite coating wear resistance
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Discussion on AFLP Molecular Markers in Piper methysticum and Pepper 被引量:2
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作者 施江 辛莉 +1 位作者 杨彦 郑学勤 《Agricultural Science & Technology》 CAS 2007年第3期5-10,19,共7页
The aim of the research was to discuss the genetic relationships between Piper methysticum, Pepper and other wild species in Pepper genus. DNA was extracted from leaves which belonged to 28 germplasms including 6 mate... The aim of the research was to discuss the genetic relationships between Piper methysticum, Pepper and other wild species in Pepper genus. DNA was extracted from leaves which belonged to 28 germplasms including 6 materials of P. methysticum, 21 maerials of cultivated and wild Pepper, 1 material of Peperomia pellucida belonged to different genus. Premiers with good band-type and high polymorphism and resolution were selected from 64 pairs of primers for AFLP amplification and the clustering analysis was conducted with MVSP3.13f software. 191 bands were amplified by 4 pairs of premiers, 189 of which had polymorphism, being 98.6%. 28 germplasms were classified into 6 different groups at the genetic similarity coefficient of 0.52 by silver staining AFLP, in which 6 materials of Piper methysticum were clustered into a single group, indicating that P. methysticum belonged to Pepper family of Pepper genus but were distantly related to the others. The research provided the basis for selecting rootstocks for P. methysticum graft, molecular identification of P. methysticum and the fingerprint construction of P. methysticum. 展开更多
关键词 Piper methysticum PEPPER Amplified fragment length polymorphism
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Studies of Site Specific DNA Binding of Small Peptides by Competitive Assays with Hoechst 33258
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作者 杨铭 朱树梅 +2 位作者 黄艳萍 胡齐悦 王夔 《Journal of Chinese Pharmaceutical Sciences》 CAS 1996年第3期141-146,共6页
With a view to finding out precisely how small peptides recognize a particular binding site of DNA, we have accomplished DNA binding studies of two peptides, H-Tyr-Arg-OH (YR) and H-Gly-Gly-His-OH (GGH) by using measu... With a view to finding out precisely how small peptides recognize a particular binding site of DNA, we have accomplished DNA binding studies of two peptides, H-Tyr-Arg-OH (YR) and H-Gly-Gly-His-OH (GGH) by using measurements in comparison with the binding between DNA and Hoechst 33258. The inhibition mode by YR and GGH to DNA binding of Hoechst 33258 was analyzed by Lineweaver-Burk plot which shows the plot of typical competitive inhibition at concentration of Hoechst 33258 from 3.66 ( 10-9 mol / L to 1.09 ( 10-8 mol / L. And it is concluded that YR binds to DNA in its minor groove (AT rich regions) with a binding constant K = 1.02 ( 108 (mol / L)-1. The GGH(s specificity is reduced at high concentration because it can also bind GC base pair. 展开更多
关键词 DNA PEPTIDE Competitive inhibitor Site specific binding
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Microstructure evolution and dislocation configurations in nanostructured Al-Mg alloys processed by high pressure torsion 被引量:3
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作者 刘满平 蒋婷慧 +3 位作者 谢学锋 刘强 李雪峰 Hans J.ROVEN 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第12期3848-3857,共10页
Microstructure evolution and dislocation configurations in nanostructured Al–Mg alloys processed by high pressure torsion (HPT) were analyzed by transmission electron microscopy (TEM) and high-resolution TEM (HR... Microstructure evolution and dislocation configurations in nanostructured Al–Mg alloys processed by high pressure torsion (HPT) were analyzed by transmission electron microscopy (TEM) and high-resolution TEM (HRTEM). The results show that the grains less than 100 nm have sharp grain boundaries (GBs) and are completely free of dislocations. In contrast, a high density of dislocation as high as 1017 m^-2 exists within the grains larger than 200 nm and these larger grains are usually separated into subgrains and dislocation cells. The dislocations are 60° full dislocations with Burgers vectors of 1/2〈110〉and most of them appear as dipoles and loops. The microtwins and stacking faults (SFs) formed by the Shockley partials from the dissociation of both the 60° mixed dislocation and 0° screw dislocation in ultrafine grains were simultaneously observed by HRTEM in the HPT Al–Mg alloys. These results suggest that partial dislocation emissions, as well as the activation of partial dislocations could also become a deformation mechanism in ultrafine-grained aluminum during severe plastic deformation. The grain refinement mechanism associated with the very high local dislocation density, the dislocation cells and the non-equilibrium GBs, as well as the SFs and microtwins in the HPT Al-Mg alloys were proposed. 展开更多
关键词 Al-Mg aluminum alloy severe plastic deformation high pressure torsion dislocation configurations grain refinement deformation mechanism
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The Multiplier Algebra of a Ternary Algebra 被引量:1
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作者 许天周 《Chinese Quarterly Journal of Mathematics》 CSCD 1992年第2期6-11,共6页
In this article, we have given the definition of the relative double multiplier (quasi-multiplier) on a ternary algebra,and studied the isomorphic problem of the multiplier algebra M(A,e) of a ternary algerbra A.
关键词 multiplier algebra ternary algebra relative arens product
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Trade Issue over Agriculture Products between China and Countries along the Silk Road Economic Belt:Features and Status 被引量:1
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作者 吾斯曼.吾木尔 布娲鹣.阿布拉 +1 位作者 骆俊澎 邵帅 《Agricultural Science & Technology》 CAS 2015年第12期2886-2889,共4页
The bilateral trade margin has been surged rapidly as cooperation over trade of agriculture products between China and countries on the silk road econom- ic belt comes closely and stands as each others' essential par... The bilateral trade margin has been surged rapidly as cooperation over trade of agriculture products between China and countries on the silk road econom- ic belt comes closely and stands as each others' essential partner, At present, however, the trade coexistence in bilateral industries that the concentration focused by markets and products is too much of the same. In light of this, sides over these countries must enhance their mutual understanding and promote more exchanges to seek tactics that can ovemome the shorthand in commercial trade,allowing win-win in the agriculture production trade. 展开更多
关键词 Trade cooperation Trade status COMPLEMENTARY
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Interactions Between Anticancer Pt(II) complexes and Human Erythrocyte Spectrin *
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作者 杨晓改 李荣昌 《Journal of Chinese Pharmaceutical Sciences》 CAS 1998年第3期9-14,共6页
The interactions between human erythrocyte spectrin(SP) and Pt(II) complexes with different composition and configuration were studied by fluorescence and circular dichroism spectra. The results showed that there are ... The interactions between human erythrocyte spectrin(SP) and Pt(II) complexes with different composition and configuration were studied by fluorescence and circular dichroism spectra. The results showed that there are 4.7×10 2 binding sites of cisplatin(CDDP) in a spectrin tetramer(SPT). Among them, about 70 sites with apparent binding constant K 1】3.47×10 6 were of highest affinity, 1.8×10 2 sites with K 2 = 3.47×10 6 were of high affinity, and other 2.2×10 2 sites with K 3 = 8.77×10 5 were of low affinity. The conformation change of spectrin, depending on the concentration of Pt(II) complex and molar ratio(R) of Pt(II) complex to spectrin, was induced by the binding of Pt(II) complexes. It indicated that the interaction of both CDDP and cis diaquodiamine platinum(DADP) with SP followed a two step first order kinetic process in the first stage (1 h), and the kinetic constants were determined. In the second stage, the induced conformation change, polymerization and depolymerization of SP were probably involved. It was noticed that in the reaction of SP and Pt(II) complexes with 1,2 cyclohexanediammine isomers as chiral carrier ligand, stereo matching played a more important role than the affinity of Pt(II) to thiol groups of SP. 展开更多
关键词 Pt (II) complex SPECTRIN CONFORMATION Binding sites Kinetic CHIRAL
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Assembly fabrication of linkers on glass surface and their effect on DNA synthesis and hybridization
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作者 沈佳尧 肖鹏峰 +3 位作者 侯鹏 祭美菊 孙啸 何农跃 《Journal of Southeast University(English Edition)》 EI CAS 2003年第2期149-154,共6页
Linkers were assembled on a glass surface based on the hydrolysis and condensation of 3-glycidoxy ̄propyltrimethoxysilane (GPS). After the assembly of GPS, four approaches were tried to open the ending epoxide group o... Linkers were assembled on a glass surface based on the hydrolysis and condensation of 3-glycidoxy ̄propyltrimethoxysilane (GPS). After the assembly of GPS, four approaches were tried to open the ending epoxide group of GPS or to further elongate the linkers. The effect of these approaches on DNA in situ synthesis and hybridization was investigated. For the spacing of the synthesis initiation sites, the wettability of the support and the length of the linking group that attaches the initiation site to the surface have direct influences on the yield of coupling reactions and the subsequent hybridization events. X-ray photoelectron spectroscopy (XPS) and mean contact angles of deionized water of the above slides were measured to assess the linker's characteristics in each procedure. It was proved that the glass slides were successfully modified and became excellent supports for the oligonucleotides synthesis. In addition, it proved best for the in situ oligonucleotides synthesis that a glass slide was in turn treated with ethylenediamine, glutaradehyde, ethanolamine and sodium borohydride solution at ambient temperature after silanized with GPS. 展开更多
关键词 LINKER assembly fabrication in situ oligonucleotide synthesis HYBRIDIZATION
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Syntheses, Structures and Magnetic Properties of Two Co(II) Coordination Polymers with 2,5-Pyridine Dicarboxylic Acid 被引量:2
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作者 XUYing YUANDa-Qiang LINZhen-Zhong WUBen-Lai LUOJun-Hua HONGMao-Chun 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2004年第11期1230-1237,共8页
The hydro(solvo)thermal reactions of cobalt powder or its chloride with 2,5- pyridine dicarboxylic acid (H2PYDC) yielded two new complexes: [Co(II)2(PYDC)2(H2O)2- (H2O)4]n 1 and {Co(II)[NH2(CH3)2]2(PYDC)2}n 2. It is o... The hydro(solvo)thermal reactions of cobalt powder or its chloride with 2,5- pyridine dicarboxylic acid (H2PYDC) yielded two new complexes: [Co(II)2(PYDC)2(H2O)2- (H2O)4]n 1 and {Co(II)[NH2(CH3)2]2(PYDC)2}n 2. It is observed that the reactive solvents result in different connectivity modes of ligand and diverse dimensional extension of crystal structures. The correlation between structure and magnetic property will be discussed in this paper. Crystal data for 1: space group P1, a = 7.0419(17), b = 8.937(2), c = 9.6182(19) ?, α = 91.532(4), β = 99.869(10), γ = 107.889(11)o, V = 565.5(2) ?3, Z = 1, Dc = 1.845 g/cm3, μ = 1.56 mm-1, F(000) = 322 , R = 0.0505 and wR = 0.1580; and those for 2: space group C2/c, a = 14.9075(6), b = 8.2523(3), c = 16.9643(2) ?, β = 100.982(2)o, V = 2048.75(11) ?3, Z = 4, Dc = 1.560 g/cm3, μ = 0.892 mm-1, F(000) = 996, R = 0.0443 and wR = 0.1134. 展开更多
关键词 HYDROTHERMAL SOLVOTHERMAL cobalt MAGNETIC 2 5-pyridine dicarboxylic acid
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High damping capacities of Mg-Cu based alloys 被引量:1
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作者 万迪庆 何柏林 +3 位作者 熊光耀 陈朝霞 王锦程 杨根仓 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2010年第B07期448-452,共5页
The dynamic mechanical analyzer(DMA)was applied to investigate the damping properties of Mg-Cu based alloys.The results show that the as-cast hypoeutectic Mg-Cu binary alloys exhibit ultra-high damping capacities,whil... The dynamic mechanical analyzer(DMA)was applied to investigate the damping properties of Mg-Cu based alloys.The results show that the as-cast hypoeutectic Mg-Cu binary alloys exhibit ultra-high damping capacities,while the eutectic Mg-Cu alloy exhibits low damping capacity.The strain amplitude dependent damping performance reveals that the dislocation damping mainly dominates in Mg-Cu alloys.Furthermore,the influence of eutectic phase on damping mechanisms of Mg-Cu binary alloys was discussed in detail and the effect of Si addition on the damping of Mg-1%Cu based alloy was also reported.Two damping peaks are observed on the temperature dependent spectrum of Mg-Cu based alloys.One is located at room temperature,which is dislocation related peak;and the other is located at moderate temperature,which is caused by the grain boundary sliding. 展开更多
关键词 Mg-Cu based alloys high damping MICROSTRUCTURE damping peaks damping mechanism
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LsrR-binding site recognition and regulatory characteristics in Escherichia coli AI-2 quorum sensing 被引量:13
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作者 Ting Xue Liping Zhao +2 位作者 Haipeng Sun Xianxuan Zhou Baolin Sun 《Cell Research》 SCIE CAS CSCD 2009年第11期1258-1268,共11页
In quorum sensing (QS) process, bacteria regulate gene expression by utilizing small signaling molecules called autoinducers in response to a variety of environmental cues. Autoinducer 2 (AI-2), a QS signaling mol... In quorum sensing (QS) process, bacteria regulate gene expression by utilizing small signaling molecules called autoinducers in response to a variety of environmental cues. Autoinducer 2 (AI-2), a QS signaling molecule proposed to be involved in interspecies communication, is produced by many species of gram-negative and gram-positive bacteria. In Escherichia coil and Salmonella typhimurium, the extracellular AI-2 is imported into the cell by a transporter encoded by the lsr operon. Upstream of the lsr operon, there is a divergently transcribed gene encoding LsrR, which was reported previously to repress the transcription of the lsr operon and itself. Here, we have demonstrated for the first time that LsrR represses the transcription of the lsr operon and itself by directly binding to their promoters using gel shift and DNase I footprinting assays. The β-galactosidase reporter assays further suggest that two motifs in both the lsrR and lsrA promoter regions are crucial for the LsrR binding. Furthermore, in agreement with the conclusion that phosphorylated AI-2 can relieve the repression of LsrR in previous studies, our data show that phospho- AI-2 renders LsrR unable to bind to its own promoter in vitro. 展开更多
关键词 quorum sensing LSRR AI-2
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Redox behavior and chemical species of arsenic in acidic aqueous system 被引量:11
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作者 Jin-qin YANG Li-yuan CHAI +1 位作者 Qing-zhu LI Yu-de SHU 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2017年第9期2063-2072,共10页
Arsenic(As)removal from smelting acidic wastewater is an urgent task.The most common method is oxidation of trivalent As(III)to pentavalent As(V)subsequently precipitated by ferric(Fe(III))salts.Foundations of redox b... Arsenic(As)removal from smelting acidic wastewater is an urgent task.The most common method is oxidation of trivalent As(III)to pentavalent As(V)subsequently precipitated by ferric(Fe(III))salts.Foundations of redox behavior and chemical species are of great importance for understanding As removal.In this work,cyclic voltammetry(CV)and UV?Vis spectroscopy were used for laboratory observation;meanwhile HSC and MINTEQ software were employed for theoretical analyses.It is found that As(III)oxidation,a multiple electron transfer reaction,is diffusion-controlled.The oxidation over-potential is very high(about0.9V)in sulfuric acid solutions(pH1.0).In addition,Fe(III)?As(V)complexes are evidenced by UV?Vis spectra and chemical species analyses in series of Fe(III)?As(V)?H2SO4?H2O solutions.Therefore,the Fe(III)and As(V)species distribution against pH values are determined and a newφ?pH diagram with inclusion of Fe?As complexes is consequently compiled based on thermodynamic data predicted by other researchers. 展开更多
关键词 ARSENIC ferric-arsenic complexes φ-pH diagram chemical species acidic wastewater
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Microstructures,tensile properties and serrated flow of Al_xCrMnFeCoNi high entropy alloys 被引量:12
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作者 Jun XU Cheng-ming CAO +1 位作者 Ping GU Liang-ming 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2020年第3期746-755,共10页
Microstructures and mechanical properties of dual-phase AlxCrMnFeCoNi (x=0.4, 0.5, 0.6, at.%) alloys were investigated. Thermomechanical processing leads to a microstructural evolution from cast dendritic structures t... Microstructures and mechanical properties of dual-phase AlxCrMnFeCoNi (x=0.4, 0.5, 0.6, at.%) alloys were investigated. Thermomechanical processing leads to a microstructural evolution from cast dendritic structures to equiaxed ones, consisting of face-centered cubic (fcc) and body-centered cubic (bcc) phases in the two states. The volume fraction of bcc phase increases and the size of fcc grain decreases with increasing Al content, resulting in remarkably improved tensile strength. Specifically, the serrated flow occurring at the medium temperatures varies from type A+B to B+C or C as the testing temperature increases. The average serration amplitude of these Al-containing alloys is larger than that of CoCrFeNiMn alloy due to the enhanced pinning effect. The early small strain produces low-density of dislocation arrays and bowed dislocations in fcc grains while the dislocation climb and shearing mechanism dominate inside bcc grains. The cross-slip and kinks of dislocations are frequently observed and high-density-tangled dislocations lead to dislocation cells after plastic deformation with a high strain. 展开更多
关键词 high-entropy alloys MICROSTRUCTURE tensile properties DISLOCATION serrated flow
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