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Synthesis and Structural Characterization of a New Cadmium(II) Complex with a Double Betaine 被引量:5
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作者 ZHENG Fa-Kun WU A-Qing +2 位作者 LI Yan GUO Guo-Cong HUANG Jin-Shun 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2005年第8期940-944,共5页
A new flexible double betaine L (L = 1,4-bis(pyridinio-4-carboxylato-N-methyl)benzene, C20H16N2O4) and its cadmium(Ⅱ) complex [Cd(H2O)aL(NO3)]NO3.H2O 1 were synthesized. Complex 1 was obtained by self-assem... A new flexible double betaine L (L = 1,4-bis(pyridinio-4-carboxylato-N-methyl)benzene, C20H16N2O4) and its cadmium(Ⅱ) complex [Cd(H2O)aL(NO3)]NO3.H2O 1 were synthesized. Complex 1 was obtained by self-assembly reaction of [Cd(NO3)2]-4H2O and L in hot water,and its crystal structure was determined by single-crystal X-ray diffraction analysis. Crystallographic data for complex 1: C20H24CdN4O14.H2O, Mr = 674.85, monoclinic, space group P21/c, a =13.7854(3), b = 14.2820(3), c = 14.9188(4) ,A°, β = 116.418(1)°, V = 2630.5(1)A°^3, Z = 4, Dc= 1.704g/cm^3,/J(MoKα) = 0.911 mm^-1, F(000) = 1368, the final R = 0.0315 and wR = 0.0768 for 3637 observed reflections with I 〉 2σ(I). In complex 1, L acts as a monodentate ligand to link a Cd(Ⅱ) ion in a novel coordination mode of double betaines. The mononuclear [Cd(H2O)aL(NO3)] units are connected through intermolecular hydrogen bonds and π-π stacking reactions to generate a 3D network. 展开更多
关键词 cadmium(Ⅱ) complex crystal structure double betaine hydrogen bonds
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Highly active double metal cyanide complexes: Effect of central metal and ligand on reaction of epoxide/CO2 被引量:3
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作者 Xing Hong Zhang Shang Chen +3 位作者 Xian Ming Wu Xue Ke Sun Fei Liu Guo Rong Qi 《Chinese Chemical Letters》 SCIE CAS CSCD 2007年第7期887-890,共4页
Various novel double metal cyanide (DMC) catalysts were successfully prepared by modifying the central metal (M) and one of cyanide ion (CN-) in Zna[M(CN)b]c complex. Such modifications have significant impact... Various novel double metal cyanide (DMC) catalysts were successfully prepared by modifying the central metal (M) and one of cyanide ion (CN-) in Zna[M(CN)b]c complex. Such modifications have significant impact on the catalytic efficiency as well as the polymer selectivity for the reaction of PO/CO2. Zn-Ni(Ⅱ) DMC is a potential catalyst for alternating copolymerization of PO/CO2,and DMC catalysts based on Zn3[Co(CN)5X]2 (X = Br^- and N3^-) exhibit moderate efficiency for the production of polycarbonates.This research presents the preliminary exploration of novel DMC complex via chemical modification of its central metal and ligand. 展开更多
关键词 double metal cyanide complexes EPOXIDE CO2 POLYMERIZATION
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RANDOM COPOLYMER OF PROPYLENE OXIDE AND ETHYLENE OXIDE PREPARED BY DOUBLE METAL CYANIDE COMPLEX CATALYST 被引量:2
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作者 Yi-jun Huang Guo-rong Qi +1 位作者 Guan-xi Chen Department of Polymer Science and Engineering, Zhejiang University Hangzhou 310027,China 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2002年第5期453-459,共7页
Copolymerization of propylene oxide (PO) and ethylene oxide (EO) using double metal cyanide (DMC) complex as the catalyst was carried out. The structure of random copolymers was confirmed by C-13-NMR and IR spectra. H... Copolymerization of propylene oxide (PO) and ethylene oxide (EO) using double metal cyanide (DMC) complex as the catalyst was carried out. The structure of random copolymers was confirmed by C-13-NMR and IR spectra. H-1-NMR analysis shows that the EO content in the copolymer is the same as that in the initial monomer feed. Moderate molecular weight copolymers with various EO content were obtained and their values of molecular weight distribution (MWD) fell in the range of 1.21-1.55. It was found that the molecular weight of copolymers is controlled by the mass ratio of EO+PO to initiator moles used, The reaction rate as well as polymer yield decrease with increasing EO content in the feed composition. 展开更多
关键词 propylene oxide ethylene oxide double metal cyanide complex
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Characterization and Crystal Structures of Two Copper(Ⅱ) Complexes Constructed by a Flexible Double Betaine Ligand 被引量:2
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作者 JIANG Ning-Yi LI Song-Lin 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2007年第2期199-205,共7页
A flexible double betaine 1,4-bis(pyridinil-4-carboxylato)-1,4-dimethylbenzene L has been used to generate two Cu(Ⅱ)-containing metal complexes that exhibit different polymeric structures: [Cu(H2O)2 L].2NO3 1 ... A flexible double betaine 1,4-bis(pyridinil-4-carboxylato)-1,4-dimethylbenzene L has been used to generate two Cu(Ⅱ)-containing metal complexes that exhibit different polymeric structures: [Cu(H2O)2 L].2NO3 1 and [Cu(H2O)3 L].2Cl.H2O 2. The crystal structures of 1 and 2 have been determined by single-crystal X-ray diffraction method. Crystal data for 1: triclinic, space group PT, a = 5.253(2), b = 7.406(3), c = 14.792(5) A, α = 84.195(5), β = 80.014(5), γ = 78.053(5)°, V= 553.2(3)A^3, Z = 1, F(000) = 293, Dc = 1.717 g/cm^3, the final R = 0.0385 and wR = 0.1079 for 1883 observed reflections (I 〉 2σ(I)); and those for 2: monoclinic, space group P21/c, a = 10.222(3), b = 25.287(7), c = 9.277(3)A, β = 93.572(5)°, V = 2393.2(12)A^3, Z = 4, F(000) = 1140, Dc = 1.540 g/cm^3, the final R = 0.0472 and wR = 0.0956 for 3204 observed reflections (I 〉2o(/)). 展开更多
关键词 1 4-bis(pyridinio-4-earboxylato)-l 4-dimethylbenzene copper(Ⅱ) complex double betaine
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Calcium chloride doped zinc-cobalt metal-cyanide complex:Unexpected highly activity towards ring-opening polymerization of propylene oxide 被引量:1
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作者 Yi Jun Huang Xing Hong Zhang +1 位作者 Zheng Jiang Hua Guo Rong Qi 《Chinese Chemical Letters》 SCIE CAS CSCD 2010年第8期897-901,共5页
Highly active calcium chloride(CaCl2) doped Zn-Co^Ⅲdouble metal-cyanide(Ca-DMC) catalysts were firstly reported.Ca-DMCs presented a very higher polymer yield(54 kg polymer/g catalyst) at relative low temperatur... Highly active calcium chloride(CaCl2) doped Zn-Co^Ⅲdouble metal-cyanide(Ca-DMC) catalysts were firstly reported.Ca-DMCs presented a very higher polymer yield(54 kg polymer/g catalyst) at relative low temperature(80-115℃) toward ringopening polymerization(ROP) of propylene oxide(PO) than did DMC catalysts without modification. 展开更多
关键词 Catalysts POLYETHERS Ring-opening polymerization metal-cyanide complex
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Reconstructing Equation of State for Dark Energy in Double Complex Symmetric Gravitational Theory
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作者 SHAO Ying GUI Yuan-Xing WANG Wei 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第6期1148-1152,共5页
We propose to study the accelerating expansion of the universe in the double complex symmetric gravitational theory (DCSGT). The universe we live in is taken as the real part of the whole spacetime MC^4(J), which ... We propose to study the accelerating expansion of the universe in the double complex symmetric gravitational theory (DCSGT). The universe we live in is taken as the real part of the whole spacetime MC^4(J), which is double complex. By introducing the spatially flat FRW metric, not only the double Friedmann equations but also the two constraint conditions py = 0 and J^2 = 1 are obtained. Farthermore, using parametric DL(z) ansatz, we reconstruct the ω/(z) and V(Ф) for dark energy from real observational data. We find that in the two cases of J = i, pJ = 0, and J = ε, pJ≠0, the corresponding equations of state ω'(z) remain close to -1 at present (z = 0) and change from below -1 to above -1. The results illustrate that the whole spacetime, i.e. the double complex spacetime MC^4(J), may be either ordinary complex (J = i, pJ = 0) or hyperbolic complex (J = ε, pJ≠ 0). And the fate of the universe would be Big Rip in the future. 展开更多
关键词 double complex symmetric gravitational theory equation of state dark energy
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Mechanism of Excited State Double Proton Transfer in 2-Amino-3-Methoxypyridine and Acetic Acid Complex
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作者 Qing-Chi Meng Guang-Hua Ren, +1 位作者 Song-Qiu Yang Tian-Shu Chu 《Chinese Physics Letters》 SCIE CAS CSCD 2018年第9期87-89,共3页
The excited-state double-proton transfer (ESDPT) mechanism of 2-amino-3-methoxypyridine and acetic acid com- plex is studied by the density functional theory (DFT) and time-dependent DFT with CAM-B3LYP functional.... The excited-state double-proton transfer (ESDPT) mechanism of 2-amino-3-methoxypyridine and acetic acid com- plex is studied by the density functional theory (DFT) and time-dependent DFT with CAM-B3LYP functional. The complex is connected through two different types of inter-molecular hydrogen bonds. After photo-excitation, both hydrogen bonds get strengthened, which can facilitate the ESDPT reaction. The scanned potential energy curve along the proton transfer coordinate indicates that the ESDPT reaction proceeds in a stepwise pattern. 展开更多
关键词 LYP CAM PT MOP Mechanism of Excited State double Proton Transfer in 2-Amino-3-Methoxypyridine and Acetic Acid complex
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Adaptive Hybrid Bivariate Double Density Discrete and Complex Wavelet for Image Denoising
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作者 Gamal Fahmy Mamdouh F. Fahmy Omar Fahmy 《Journal of Computer and Communications》 2023年第2期39-56,共18页
Image denoising is an important step in eliminating any noise impact in any image transmission process. Recently we presented two approaches for Bivariate based image denoising. They were Double Density Discrete Wavel... Image denoising is an important step in eliminating any noise impact in any image transmission process. Recently we presented two approaches for Bivariate based image denoising. They were Double Density Discrete Wavelet Transform (DD DWT) and Double Density Dual Tree Complex Wavelet Transform (DD CWT). In both techniques we decomposed noisy images with either DD DWT or DD CWT decompositions and then applied the Bivariate based denoising technique for noise removal. In this paper we propose an adaptive hybrid technique for Bivariate based image denoising that is based on the synthesis of DD-DWT bands or DD-CWT bands but with different weights, to deliver enhanced image features with less denoising impact especially around image edges, which is the most effected by noisy transmission channels. This proposed technique has been also enhanced by edge sharpening and Eigen analysis, as two separate stages. Simulation result comparisons have been performed between the proposed hybrid band adaptive DD-DWT and DD-CWT technique and the two primary techniques DD-DWT, DD- CWT, as well as other superior literature techniques such the original bivariate denoising technique with both original Complex Wavelet Transform and Double Density decompositions. This work in specific compares between Double Density DWT and Double Density CWT decompositions, proposes new filter design that suits each of them and proposes a hybrid technique between as will be shown. 展开更多
关键词 complex Wavelet Image Deniosing double Density Wavelets
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High efficiency spreading spectrum modulation using double orthogonal complex sequences
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作者 Shi Xiaohong 《Engineering Sciences》 EI 2012年第5期71-75,共5页
This paper presents a novel scheme of high efficiency spreading spectrum modulation using double orthogonal complex sequences (DoCS). In this scheme, input data bit-stream is split into many groups with length M. Ea... This paper presents a novel scheme of high efficiency spreading spectrum modulation using double orthogonal complex sequences (DoCS). In this scheme, input data bit-stream is split into many groups with length M. Each group is then mapped into a word of width M and then utihzed to select one sequence from 2u-2 DoCS sequences each with length L. After that, the selected sequence is modulated on carrier in quadrature phase shift keying (QPSK) mode. In addition, a new method named forward phase correction (FPC) is put forward for carrier recovery. Theoretical analysis and bit-error-ratio(BER) experiment results indicate that the proposed scheme has better performance than the conventional direct sequence spread spectrum(DSSS) scheme both in bandwidth efficiency and processing gain of the receiver. 展开更多
关键词 modulation and demodulation high efficiency spreading spectrum modulation forward phase correction double orthogonal complex sequences
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The Double-Double Effect of Lanthanide Complexes with Styrene-Acrylic Acid Copolymer
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作者 于广谦 李玉良 刘丛明 《Journal of Rare Earths》 SCIE EI CAS CSCD 1992年第2期148-150,共3页
The double-double (or tetrad) effect of low molecular lanthanide complexes has been reportedsince the effect was discovered by Fidelis and Siekierski.However,so far no description concerning thedouble-double effect of... The double-double (or tetrad) effect of low molecular lanthanide complexes has been reportedsince the effect was discovered by Fidelis and Siekierski.However,so far no description concerning thedouble-double effect of macromolecular lanthanide complexes has been published in literature.We have been successful in preparing lanthanide complexes with styrene-acrylic acid copolymer,someof which exhibite high activitiest in butadiene polymerization.It was found that the complexes showedthe double-double effect as they were characterized.In the present paper,the SAAC·Ln IR spectra whichcharacterize the double-double effect have been discussed in detail. 展开更多
关键词 double-double effect Lanthanide complexes COPOLYMER
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Two Cases of Double Crush Syndrome Progressing to Complex Regional Pain Syndrome
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作者 Carmine Vincifora Troy Buck 《Open Journal of Anesthesiology》 2015年第7期183-186,共4页
The double crush syndrome is described as an increased risk of distal nerve injury after a more proximal injury. This was a case series of two patients who developed Complex Regional Pain Syndrome under circumstances ... The double crush syndrome is described as an increased risk of distal nerve injury after a more proximal injury. This was a case series of two patients who developed Complex Regional Pain Syndrome under circumstances when a double crush phenomenon could have occurred. Both initially had spinal stenosis and subsequent spinal surgery. Both later had crush injuries to a unilateral lower extremity, which progressed to CRPS. There is no documented correlation between double crush syndrome and CRPS;however, these cases raise awareness about a heightened propensity for CRPS in such patients, which will lead to earlier, accurate diagnosis and treatment. 展开更多
关键词 complex Regional Pain SYNDROME CRPS double-Crush SYNDROME SPINAL STENOSIS SPINAL Surgery
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复杂光照与背景下的Double肤色模型人脸检测算法 被引量:1
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作者 于明慧 陈玮 《江南大学学报(自然科学版)》 CAS 2014年第5期517-522,共6页
针对复杂光照与背景的图像中难以准确检测出人脸的情况,提出一种复杂光照与背景下的Double肤色模型人脸检测算法。采用一种改进的光照补偿方法对图像进行光照预处理,融合改进的高斯肤色模型和非线性肤色模型,通过对融合算法进行收敛性... 针对复杂光照与背景的图像中难以准确检测出人脸的情况,提出一种复杂光照与背景下的Double肤色模型人脸检测算法。采用一种改进的光照补偿方法对图像进行光照预处理,融合改进的高斯肤色模型和非线性肤色模型,通过对融合算法进行收敛性验证与实例检验,证明了其可行性。实验结果表明,该算法能够对复杂背景及光照下多人脸、多姿态、遮挡、动态视频图像等情况的人脸检测有较好的检测效果。 展开更多
关键词 光照补偿 double肤色模型 复杂光照 多姿态人脸检测
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苯乙烯——丙烯酸共聚物载体稀土配合物的Double-Double效应
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作者 王世英 于广谦 李玉良 《长春光学精密机械学院学报》 1993年第1期1-4,共4页
研究了苯乙烯——丙烯酸共聚物载体稀土配合物(SAAC·Ln)的红外光谱,证明SAAC·Ln具有双齿配位结构(B)发现SAAC·Ln的V_(as)(COO^-)与V_s(COO^-)的振动频率差(△_u)与稀土元素原子序数关系呈现出对称的DoubLe-DoubLe效应.
关键词 苯乙烯 丙烯酸 共聚物 稀土配合物
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Syntheses and Crystal Structure of Erbium(Ⅲ) Coordination Polymers with Two Flexible Double Betaine Ligands 被引量:1
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作者 毛江高 吴海涛 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 1998年第5期353-360,共8页
Two new polymeric erbium(Ⅲ) complexes of two flexible double betaine ligands have been synthesized and characterized by X-ray analysis. In {[Er(L1)(H2O)4)Cl3 H2O}n (1) (L1 = 4, 4’ -trimethylenedipyridinio-N, N’-dia... Two new polymeric erbium(Ⅲ) complexes of two flexible double betaine ligands have been synthesized and characterized by X-ray analysis. In {[Er(L1)(H2O)4)Cl3 H2O}n (1) (L1 = 4, 4’ -trimethylenedipyridinio-N, N’-diacetate ), the erbium(Ⅲ) ions form a two-dimensional metal carboxylate layer in which each pair of Er(Ⅲ) atoms is bridged by two syn-anti μ-carboxylato-o,o’ groups, Adjacent layers arecross-linked through hydrogen bonds among aqua ligands, lattice water molecules andchloride ions to form a three-dimensional network. Complex l, C17 H28 N2 O9 ErC13 (Mr =676.0) is monoclinic, space group C2, with a= 27. 408(4), b= 9. 645 (3), c= 9. 423(2) A, p=1loo. 85(1)’, V=2446. 2(9) A’, Z=4, D=l. 836 g/cm’, F(OOO) =1332, μ(MoKa) = 38.06 cm-1, R=0. 048 for 2451 reflections with I>2σ(I). { [Er(L2 ) (H2O)4]Cl3. 5H2O}. (2) (L2=1, 3-bis (pyridinio-4-carboxylato) propane) comprises lanthanide carboxylate chains built from centrosymmetric dimeric units crosslinked by a pair of L2 ligands, discrete anions and lattice water molecules. In the dimeric unit of complex 2, each pair of metal ions is bridged by four syn-syn μ-carboxylatoO, O’ groups that are oriented nearly perpendicular to each other about the metal-metalaxis. The metal carboxylate chains of complex 2 are further cross-linked by hydrogenbonds to form a three-dimensional network. Complex 2, C15 H32 N2O13 ErCl3 (Mr=722.0) belongs to the monoclinic space group C2/m with a=16. 564 (3), b=15. 839(3), c=11. 792(4) , β=122. 27(1)°, V=2616(1), Z=4, Dc=1.833 g/cm3,F(000) =1436, μ (MoKa) = 35. 75 cm-1, R =0.043 for 2436 observed reflectionswithI>2σ(I). 展开更多
关键词 crystal structure coordination polymer erbium(Ⅲ) complex double betaine
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敏感环境下地下水池基坑围护施工技术
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作者 苏宇 《山西建筑》 2025年第2期68-71,81,共5页
杨树浦水厂深度处理改造工程具有地质条件复杂、场地工况敏感、施工组织及环境保护要求高等特点。结合周边建筑物密集,且离运营中的文保工业建筑最近距离仅为15 m的特点,从支撑选型、回填及降水、土方开挖等方面介绍了敏感环境下地下水... 杨树浦水厂深度处理改造工程具有地质条件复杂、场地工况敏感、施工组织及环境保护要求高等特点。结合周边建筑物密集,且离运营中的文保工业建筑最近距离仅为15 m的特点,从支撑选型、回填及降水、土方开挖等方面介绍了敏感环境下地下水池处理改造基坑围护施工技术,有效地保障了重大工程的高效、安全实施,为今后类似环境下地下结构建造涉及到的基坑施工提供了借鉴和参考。 展开更多
关键词 硬咬合排桩 复杂地质 文保建筑 双C环形支撑 基坑开挖 工期高效
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Structure and Luminescent Properties of the First Cadmium Complex with Isophthalate and Di-pyrazole Ligands
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作者 刘同飞 张明熹 +1 位作者 张卫国 崔广华 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2011年第4期508-513,共6页
The title complex [Cd(IPA)L(H2O)]n(1,H2IPA = isophthalic acid,L = 1,4-bis(pyra-zole-1-ylmethyl)benzene) has been hydrothermally synthesized,and characterized by elemental analyses,IR spectroscopy,TGA and X-ray... The title complex [Cd(IPA)L(H2O)]n(1,H2IPA = isophthalic acid,L = 1,4-bis(pyra-zole-1-ylmethyl)benzene) has been hydrothermally synthesized,and characterized by elemental analyses,IR spectroscopy,TGA and X-ray single-crystal diffraction.It crystallizes in the triclinic system,space group P1 with a = 9.3060(6),b = 10.2374(7),c = 11.9706(8) ?,α = 73.804(6),β = 77.883(5),γ = 85.942(5)°,V = 1070.7(1) ?3,Z = 2,C22H20CdN4O5,Mr = 532.82,Dc = 1.653 g/cm3,μ = 1.062 mm-1,λ(MoKα) = 0.71073 ?,F(000) = 536,R = 0.0392 and wR = 0.0640 for 3751 observed reflections with I 2σ(I).Crystal structure analysis showed that complex 1 has a 1D double chain structure,which is assembled together through strong O-H...O hydrogen bonding interactions between coordinated water molecules and carboxylate groups of isophthalate to form a 2D supramolecular network.In addition,the solid-state fluorescent spectrum of 1 exhibits strong emission at 364 nm. 展开更多
关键词 1D double chain Cd(II) complex di-pyrazole ligand ISOPHTHALATE luminescent property
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Zircon age depth-profiling sheds light on the early Caledonian evolution of the Seve Nappe Complex in west-central J?mtland
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作者 Katarzyna Walczak Christopher J.Barnes +2 位作者 Jaroslaw Majka David G.Gee Iwona Klonowska 《Geoscience Frontiers》 SCIE CAS CSCD 2022年第2期460-470,共11页
The Scandinavian Caledonides comprise nappe stacks of far-travelled allochthons that record closure of the Iapetus Ocean and subsequent continental collision of Baltica and Laurentia.The Seve Nappe Complex(SNC)of the ... The Scandinavian Caledonides comprise nappe stacks of far-travelled allochthons that record closure of the Iapetus Ocean and subsequent continental collision of Baltica and Laurentia.The Seve Nappe Complex(SNC)of the Scandinavian Caledonides includes relics of the outermost Baltoscandian passive margin that were subducted to mantle depths.The earliest of the deep subduction events has been dated to ca.500-480 Ma.Evidence of this event has been reported from the northern exposures of the SNC.Farther south in the central and southern segments of the SNC,(ultra)high-pressure rocks have yielded younger ages in the range of ca.470-440 Ma.This study provides the first record of the early Caledonian event in the southern SNC.The evidence has been obtained by depth profiling of zircon grains that were extracted from the Tv?r?klumparna microdiamond-bearing gneiss.These zircon grains preserve eclogite facies overgrowths that crystallized at 482.6±3.8 Ma.A second,chemically-distinct zircon overgrowth records granulite facies metamorphism at 439.3±3.6 Ma,which corroborates previous geochronological evidence for granulite facies metamorphism at this time.Based on these results,we propose that the entire outer margin of Baltica was subducted in the late Cambrian to early Ordovician,but the record of this event may be almost entirely eradicated in the vast majority of lithologies by pervasive late Ordovician to early Silurian metamorphism. 展开更多
关键词 Caledonian Orogeny Seve Nappe complex Zircon geochronology Depth profiling HP/UHP metamorphism double dunking
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Effects of PI3-k/Akt short hairpin RNA on proliferation, fibronectin production and synthesis of thrombospondin-1 and transforming growth factor-beta(1 ) in glomerular mesangial cells induced by sublytic C5b-9 complexes 被引量:5
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作者 Gao, L. Zhang, Y. Qiu, W. Xu, W. Feng, X. Ren, J. Jiang, X. Wang, H. Zhao, D. Wang, Y. 《南京医科大学学报(自然科学版)》 CAS CSCD 北大核心 2009年第3期344-344,共1页
关键词 连接蛋白 凝血栓蛋白 临床分析 治疗方法 白血病
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Naked DNA in cells:An inducer of major histocompatibility complex molecules to evoke autoimmune responses?
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作者 Yuqian Luo Aya Yoshihara +3 位作者 Kenzaburo Oda Yuko Ishido Naoki Hiroi Koichi Suzuki 《World Journal of Translational Medicine》 2016年第1期46-52,共7页
The major histocompatibility complex(MHC) is the exclusive chaperone that presents intracellular antigens,either self or foreign to T cells.Interestingly,aberrant expression of MHC molecules has been reported in vario... The major histocompatibility complex(MHC) is the exclusive chaperone that presents intracellular antigens,either self or foreign to T cells.Interestingly,aberrant expression of MHC molecules has been reported in various autoimmune target tissues such as thyroid follicular cells in Grave's disease.Herein,we review the discovery of an unexpected effect of cytosolic doublestranded DNA(ds DNA),despite its origins,to induce antigen processing and presenting genes,including MHC molecules,in non-immune cells.Moreover,we highlight several recent studies that suggest cell injury endows thyroid epithelial cells with a phenotype of mature antigen presenting cells by inducing multiple antigen processing and presenting genes via releasing genomic DNA fragments into the cytosol.We discuss the possibility that such cytosolic ds DNA,in naked form without binding to histone proteins,might be involved in the development of cell damage-triggered autoimmune responses.We also discuss the possible molecular mechanism by which cytosolic ds DNA can induce MHC molecules.It is reasonable to speculate that cytosolic ds DNA-induced MHC class Ⅰ is partially due to an autocrine/paracrine effect of type Ⅰ interferon(IFN).While the mechanism of cytosolic ds DNA-induced MHC class Ⅱ expression appears,at least partially,distinct from that mediated by IFN-γ.Further in-depth are required to clarify this picture. 展开更多
关键词 CYTOSOLIC double-STRANDED DNA Major HISTOCOMPATIBILITY complex MOLECULES AUTOIMMUNE response Antigen presentation Tissue injury
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Complex Heat Pipe System
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作者 王宗伟 田晓亮 +2 位作者 DU Qi-hang REN Jie ZHOU Wen-quan 《科技信息》 2012年第36期225-226,共2页
Based on the analysis for the situation about heat pipe,this paper points out that high efficiency micro heat pipe,high temperaturelarge heat pipe,high efficiency heat pipe reaction equipment and high efficiency heat ... Based on the analysis for the situation about heat pipe,this paper points out that high efficiency micro heat pipe,high temperaturelarge heat pipe,high efficiency heat pipe reaction equipment and high efficiency heat pipe heat exchange equipment are the developing di-rection of the heat pipe,and the complex heat pipe system is a new heat pipe idea that can satisfy the modern large heat pipe heat exchangeequipment and the high efficiency heat pipe heat exchange equipment.A new complex heat pipe system that is called double circulation con-trollable heat pipe system is advanced and several basic structure modes are given in this paper.The working principle and the basic character-istics about this special heat pipe system are also introduced and analyzed. 展开更多
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