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Synthesis of a Novel Aromatic Diamino-bridged Bis(β-cyclodextrin) and its Inclusion Complexation with Dyes Molecules 被引量:1
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作者 Yah ZHAO Xiao Qing LIU +2 位作者 Hong You ZHU Zi Ming YANG Rong HUANG 《Chinese Chemical Letters》 SCIE CAS CSCD 2006年第12期1543-1546,共4页
A novel brideed bis(β-cvclodextrin), 4, 4'-diaminodiphenyl ether-bfiged-bis (6-aimino-6-deoxv-β-cyclodextrin) 3, has been synthesized and its inclusion complexation behavior with three linear'guest dyes (AR, ... A novel brideed bis(β-cvclodextrin), 4, 4'-diaminodiphenyl ether-bfiged-bis (6-aimino-6-deoxv-β-cyclodextrin) 3, has been synthesized and its inclusion complexation behavior with three linear'guest dyes (AR, NR and MB ) has been investigated by. means of fluorescence spectrometry. The-result obtained demonstrated that the novel bridged bis(β-cyclodextnn) showed much higher affinities towards guest dyes than native β-cyclodextrin. 展开更多
关键词 bridged bis(β-cyclodextrin)s cooperative binding inclusion complexation dye.
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Synthesis and Crystal Structure of the Ladder-like Organotin Complex: μ-pentaoxygen bridged penta(bis-benzyltin) bis-salicylate 被引量:7
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作者 WANG Jian-Qiu CHEN Zhi-Min ZENG Rong-Ying KUANG Dai-Zhi FENG Yong-Lan ZHANG Fu-Xing 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2005年第12期1387-1392,共6页
A novel organotin complex of μ-pentaoxygen bridged penta(bis-benzyltin) bissalicylate has been synthesized by the reaction of bis-benzyltin oxide and salicylic acid and its structure has been determined by X-ray di... A novel organotin complex of μ-pentaoxygen bridged penta(bis-benzyltin) bissalicylate has been synthesized by the reaction of bis-benzyltin oxide and salicylic acid and its structure has been determined by X-ray diffraction. The crystal belongs to monoclinic, space group P21/n with a = 1.7206(5), b = 2.1401(6), c = 2.1488(6)nm, β= 93.325(5)°, V = 7.899(4) nm^3, Z = 4, Dc = 1.564 g/cm^3,μ(MoKα) = 16.17cm^-1, Mr = 1859.94, F(000) = 3692, R1= 0.0755 and wR2= 0.1557. According to structural analysis, the coordination geometry of tin is a distorted trigonal bipyramid, and the ladder-like structure is shaped by four Sn2O2 planar four-membered rings. 展开更多
关键词 μ-pentaoxygen bridged penta(bis-benzyltin) bis-salicylate synthesis crystal structure
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FERROMAGNETIC INTERACTION BETWEEN GADOLINIUM(Ⅲ) AND COPPER (Ⅱ)IONS IN N,N'-BIS(2-AMINOPROPYL)OXAMIDO COPPER(Ⅱ) BRIDGED BINUCLEAR Gd(Ⅲ)-Cu(Ⅱ) COMPLEX
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作者 Yan Tuan LI Dai Zheng LIAO +2 位作者 Zong Hui JIANG Shi Ping YAN and Geng Lin WANG(Department of Chemisstry. Nankai University. Tianjin. 300071) 《Chinese Chemical Letters》 SCIE CAS CSCD 1994年第8期697-700,共4页
The heterobinuclear complex of formula Cu (oxap )Gd(phen)2 (CIO4 )3 has been synthesized, where oxap denotes the N, N'-bis (2-aminopropyl )oxamido dianion and phen represents 1,10-phenanthroline. The complex was c... The heterobinuclear complex of formula Cu (oxap )Gd(phen)2 (CIO4 )3 has been synthesized, where oxap denotes the N, N'-bis (2-aminopropyl )oxamido dianion and phen represents 1,10-phenanthroline. The complex was characterized with ESR and variable temperature magnetic susceptibility (4- 300K). The least-squares fit of the experimental sosceptibilities yielded J=2. 25cm-1. The observed Gd (Ⅲ)-Cu (Ⅱ) coupling is ferromagnetic.One Plausible mechanism that can cause a ferromagnetic coupling between Gd(Ⅱ) and Cu (Ⅱ) is discussed in terms of spin-polarization. 展开更多
关键词 GD biNUCLEAR bridged bis AMINOPROPYL CU
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One pot synthesis of bis-silicon-bridged stilbene derivatives
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作者 Chen Hui Li Hua Yu Qiu Cai Hong Xu 《Chinese Chemical Letters》 SCIE CAS CSCD 2007年第12期1436-1438,共3页
Bis-silicon-bridged stilbene derivatives were synthesized in a modified procedure that combined the preparation of bis[2- (silyl)phenyl]acetylene and its intramolecular reductive cyclization in one pot. The results ... Bis-silicon-bridged stilbene derivatives were synthesized in a modified procedure that combined the preparation of bis[2- (silyl)phenyl]acetylene and its intramolecular reductive cyclization in one pot. The results indicated that the one pot approach produced target products in a comparable yield to that of the two-step method reported previously. 展开更多
关键词 bis-silicon-bridged stilbene Reductive cyclization One pot synthesis
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Syntheses,Structures and Vitro Anticancer Activities ofμ_2-O-andμ_2-Dimethylglyoximato-bridgedμ_3-O-Tris[di(m-fluorobenzyl)tin]Bis(dimethylglyoximate) 被引量:1
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作者 张复兴 邝代治 +5 位作者 李璇捷 梁芳 冯泳兰 朱小明 庾江喜 蒋伍玖 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2016年第10期1510-1516,共7页
μ_2-O-and μ_2-dimethylglyoximato-bridged μ_3-O-tris[di(m-fluorobenzyl)tin] bis(dimethylglyoximate)(1) has been synthesized by the reaction of di(m-fluorobenzyl)tin dichloride with dimethylglyoxime. Complex ... μ_2-O-and μ_2-dimethylglyoximato-bridged μ_3-O-tris[di(m-fluorobenzyl)tin] bis(dimethylglyoximate)(1) has been synthesized by the reaction of di(m-fluorobenzyl)tin dichloride with dimethylglyoxime. Complex 1 was characterized by means of IR,~1H NMR,elemental analysis and X-ray diffraction. It crystallizes in orthorhombic system,space group Pna21 with a = 2.22172(12),b = 1.05566(6),c = 2.15577(12) nm,V = 5.0561(5) nm^3,Z = 4,C_(50)H_(50)F_6N_4O_6Sn_3,Mr = 1273.01,Dc = 1. 6721 g/cm3,μ_(MoΚα) = 15.44 cm^(-1),F(000) = 2520,R = 0.0281 and wR = 0.0683. The stabilities,orbital energies and composition characteristics of some frontier molecular orbitals of 1 have been investigated with the quantum chemistry calculation. The properties of thermogravimetric and vitro anticancer activities of the compound have been discussed. 展开更多
关键词 μ2-O-and μ2-dimethylglyoximato-bridged μ3-O-tris[di(m-fluorobenzyl)tin] bis(dimethylglyoximate) synthesis crystal structure vitro anticancer activity
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基于贝叶斯自优化Bi-LSTM组合网络的高速铁路轨道-桥梁系统震后响应预测方法 被引量:1
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作者 彭康 蒋丽忠 +3 位作者 周旺保 余建 向平 吴凌旭 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第3期965-975,共11页
中国高速铁路(HSR)规划建设逐渐向地震易发地区延伸,亟需一种及时、准确的灾后地震响应快速预测方法,以实现高速铁路系统运输生命线安全的快速评估。本文提出了一种基于贝叶斯自优化双向长短期记忆(Bi-LSTM)网络的快速预测方法,以经过... 中国高速铁路(HSR)规划建设逐渐向地震易发地区延伸,亟需一种及时、准确的灾后地震响应快速预测方法,以实现高速铁路系统运输生命线安全的快速评估。本文提出了一种基于贝叶斯自优化双向长短期记忆(Bi-LSTM)网络的快速预测方法,以经过实验验证的高速铁路轨道-桥梁系统有限元模型地震动响应计算数据为样本,将预测地震响应和有限元计算结果进行比较,验证所提方法的精度和鲁棒性,表明该方法在预测高速铁路桥梁结构的非线性地震反应方面是有效的,且高速铁路轨道-桥梁系统的不同预测位置对预测精度的影响不明显;此外,为了降低神经网络训练数据量需求,提出了一种基于离散小波分解的分层聚类算法,结果表明,基于小波分解的分层聚类方法在保证预测精度的同时,有效地减少了训练地震集的输入数量。 展开更多
关键词 高速铁路轨道-桥梁系统 贝叶斯优化 bi-LSTM神经网络 离散小波分解 聚类分析
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Bridging of Calixarenes with N,N′-Bis(Chloroacetyl)Propylenediamine
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作者 LIJun WANGWei GONGShu-ling CHENYuan-yin 《Wuhan University Journal of Natural Sciences》 CAS 2004年第4期509-512,共4页
A new bridging reagent, N,N ′\|bis(chloroacetyl)propylenediamine was used to explore the relative activity and bridging pattern of p \|tert\|buty lcalix\arene, p \|tert\|buty lcalix\arene and butyl... A new bridging reagent, N,N ′\|bis(chloroacetyl)propylenediamine was used to explore the relative activity and bridging pattern of p \|tert\|buty lcalix\arene, p \|tert\|buty lcalix\arene and butylcalix\arene. It was found that the bridging reaction is selectively, at least, preferably at 1,3\|position for p \|tert\|butylcalix\arene and p \|tert\|b utylcalix\arene, 1,5\|position for p \|tert \|butylcalix\arene. Taking the yield of bridged calixarene as a comparsion standard, the activity decreases with the increasing of the number of phenolic units in calixarene. 展开更多
关键词 N N ′-bis(chloroacetyl)propylenediamine bridging reaction CALIXARENE
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基于迁移学习和Bi-LSTM神经网络的桥梁温度-应变映射建模方法 被引量:2
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作者 方佳畅 黄天立 +1 位作者 李苗 王亚飞 《振动与冲击》 EI CSCD 北大核心 2023年第12期126-134,186,共10页
为快速构建并准确预测温度作用引起的斜拉桥主梁应变用于结构状态评估,基于某大跨度斜拉桥主梁超过1年的温度和应变监测数据,提出了一种基于迁移学习和双向长短时记忆(bi-directional long short-term memory,Bi-LSTM)神经网络的斜拉桥... 为快速构建并准确预测温度作用引起的斜拉桥主梁应变用于结构状态评估,基于某大跨度斜拉桥主梁超过1年的温度和应变监测数据,提出了一种基于迁移学习和双向长短时记忆(bi-directional long short-term memory,Bi-LSTM)神经网络的斜拉桥温度-应变映射模型建立方法。首先,利用解析模态分解(analytical mode decomposition,AMD)去噪应变数据,得到仅由温度引起的应变响应;其次,选择温度和某一测点应变数据构成数据集,采用Bi-LSTM神经网络训练该数据集,并通过网络结构和超参数优化建立温度-应变Bi-LSTM基准模型;最后,利用迁移学习方法,将已训练好的基准模型中部分参数迁移到其他温度-应变数据集,建立相应的温度-应变映射被迁移模型,并与未采用迁移学习的神经网络训练方法进行对比。研究结果表明,相比直接建立的温度-应变Bi-LSTM神经网络映射模型,采用迁移学习方法建立的被迁移模型,其拟合精度均高于所用的基准模型,且训练时间短,预测误差小。 展开更多
关键词 结构健康监测 大跨度斜拉桥 温度-应变映射模型 迁移学习 双向长短时记忆(bi-LSTM)神经网络
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Synthesis and photochromic behavior of mono-,and biphotochromic system linked by p-phenylene bridge 被引量:1
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作者 N.O.Mahmoodi K.Tabatabaeian A.Ghavidast 《Chinese Chemical Letters》 SCIE CAS CSCD 2010年第10期1199-1202,共4页
The synthesis of mono- and bis-1,3-diazabicyclo[3.1.0]hex-3-ene derivatives with indole ring and p-phenylene spacer, which behave as photochromic materials, is reported. The structure-photochromic behavior relationsh... The synthesis of mono- and bis-1,3-diazabicyclo[3.1.0]hex-3-ene derivatives with indole ring and p-phenylene spacer, which behave as photochromic materials, is reported. The structure-photochromic behavior relationship (SPBR) of the synthesized compounds has been analyzed. 展开更多
关键词 biphotochromic p-Phenylene bridge bis-l 3-diazabicyclo[3.1.0]hex-3-ene
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An Interesting Approach to Bis-calix[5]arene Analogue from Calix[6]arene
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作者 Hai Bing LI Yuan Yin CHEN Shu Ling GONG 《Chinese Chemical Letters》 SCIE CAS CSCD 2002年第3期205-206,共2页
By 1,4-bridging of p-tert-butylcalix [6] arene with 2,6-bis (bromomethyl)-4-methyl- anisole, a new type of bis-calix [5] arene analogue was obtained in high yield..
关键词 bis-calix [5] arene calyx [6] arene bridging.
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基于双重移相控制的双向全桥DC-DC变换器最小回流功率分段优化控制 被引量:1
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作者 孙标广 李静争 张迁迁 《电网技术》 EI CSCD 北大核心 2024年第3期1263-1272,共10页
双向全桥DC-DC变换器以其重量轻、高功率密度、能量双向流动等优点成为直流微电网中不可或缺的一部分。但双向全桥DC-DC变换器在传统的单重移相控制下存在回流功率和电流应力等问题,尤其当输入电压和输出电压不匹配时,回流功率和电流应... 双向全桥DC-DC变换器以其重量轻、高功率密度、能量双向流动等优点成为直流微电网中不可或缺的一部分。但双向全桥DC-DC变换器在传统的单重移相控制下存在回流功率和电流应力等问题,尤其当输入电压和输出电压不匹配时,回流功率和电流应力会显著增加。针对输入电压和输出电压不匹配的情况,该文提出了一种双向全桥DC-DC变换器在双重移相下的最小回流功率控制策略。该控制策略通过对回流功率进行分段优化,得到了变换器在不同传输功率范围下的最优移相角。通过将所提控制策略和传统的双重移相控制进行对比分析,发现该文所提控制策略具有更小的回流功率和电流应力,提升了变换器的效率。最后基于所提控制策略搭建了实验样机,实验结果验证了控制策略的正确性和有效性。 展开更多
关键词 双向全桥DC-DC变换器 双重移相控制 最小回流功率 电流应力 直流微电网
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环糊精键合相拆分和测定人血浆中β-受体阻滞剂对映体
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作者 黄志琴 曾庆丽 +1 位作者 李丹 李来生 《分析科学学报》 CAS CSCD 北大核心 2024年第3期263-269,共7页
本文采用一种新型的桥联双β-环糊精固定相,通过优化色谱条件,实现了常见β-受体阻滞剂卡维地洛、阿罗洛尔和阿替洛尔6种对映体的完全分离,分离度分别为1.6、1.9和1.7。以R-阿普洛尔为内标,建立了一种能同时测定人体血浆中上述6种对映... 本文采用一种新型的桥联双β-环糊精固定相,通过优化色谱条件,实现了常见β-受体阻滞剂卡维地洛、阿罗洛尔和阿替洛尔6种对映体的完全分离,分离度分别为1.6、1.9和1.7。以R-阿普洛尔为内标,建立了一种能同时测定人体血浆中上述6种对映体含量的液相色谱新方法。血浆样品碱化后用乙酸乙酯提取和净化,选择极性有机相体系(乙腈/甲醇/三乙胺/冰乙酸),通过梯度洗脱完全拆分对映体,柱后二极管阵列检测(275 nm),内标法定量。结果表明,在各自质量浓度范围内,6种β-受体阻滞剂对映体波长响应值与含量呈良好的线性关系(R2为0.9923~0.9989)。对映体的检测限(S/N=3)和定量限(S/N=10)分别在0.4~1.5 mg/L和1.5~4.0 mg/L范围内,样品加标平均回收率为85.96%~103.88%,测定结果的日内和日间的相对标准偏差范围分别为1.88%~3.29%和3.02%~5.17%。该方法具有操作简便、结果准确性和手性分离度高等优点,可同时测定多个对映体,提高分析效率,降低测试成本。 展开更多
关键词 Β-受体阻滞剂 桥联双β-环糊精液相色谱固定相 手性拆分 对映体定量 人体血浆
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庞敏“五位一体”诊疗思路治疗心肌桥经验
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作者 刘之然 吴希泽 +2 位作者 王晓玉 庞敏 高静 《辽宁中医杂志》 CAS 北大核心 2024年第2期49-53,共5页
冠状动脉心肌桥是一种先天冠脉变异疾病,常出现胸闷、胸痛等临床症状,西医治疗指南尚未完善,常通过药物、手术和介入方式进行治疗。中医将其作为胸痹疾病来进行治疗,各家经临床证实皆取得较好疗效。庞敏教授在从业中总结出“天、人、证... 冠状动脉心肌桥是一种先天冠脉变异疾病,常出现胸闷、胸痛等临床症状,西医治疗指南尚未完善,常通过药物、手术和介入方式进行治疗。中医将其作为胸痹疾病来进行治疗,各家经临床证实皆取得较好疗效。庞敏教授在从业中总结出“天、人、证、机、病——五位一体”的处方思路,临床中应用于治疗心肌桥疗效显著,患者胸闷、胸痛可见有效缓解。文章旨在介绍吾师庞敏教授的诊疗思路,为临床中治疗冠状动脉心肌桥提供新思维。 展开更多
关键词 冠状动脉心肌桥 五位一体 胸痹 辨天 辨人 辨证 辨机 辨病
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硫脲基桥联双四苯乙烯有机荧光传感器的制备及在水介质中叶黄素检测上的应用
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作者 江晟杰 《理化检验(化学分册)》 CAS CSCD 北大核心 2024年第10期1021-1026,共6页
以4-羟基四苯乙烯与溴乙酸乙酯为起始原料设计并合成一种硫脲基桥联双四苯乙烯(Bis-S)有机荧光传感器。将Bis-S溶解在95%(体积分数)四氢呋喃溶液中制备Bis-S溶液,采用荧光光谱仪在激发波长360 nm、发射波长468 nm下测量叶黄素加入前后Bi... 以4-羟基四苯乙烯与溴乙酸乙酯为起始原料设计并合成一种硫脲基桥联双四苯乙烯(Bis-S)有机荧光传感器。将Bis-S溶解在95%(体积分数)四氢呋喃溶液中制备Bis-S溶液,采用荧光光谱仪在激发波长360 nm、发射波长468 nm下测量叶黄素加入前后Bis-S体系的荧光强度。结果显示:在Bis-S溶液或含Bis-S的传感试纸中加入叶黄素,叶黄素与Bis-S按照物质的量比1∶1结合并被Bis-S空腔包裹,Bis-S体系亮蓝色荧光猝灭;在Bis-S溶液或含Bis-S的传感试纸中加入共存生物分子鸟嘌呤、色氨酸、果糖、胞嘧啶、腺嘌呤、胸腺嘧啶、维生素B1、维生素B2、淀粉、蔗糖、葡萄糖、咖啡因、脯氨酸后,Bis-S体系荧光强度无明显变化;在含叶黄素的Bis-S溶液中加入上述共存生物分子,体系荧光强度较未加入共存生物分子的变化不大,说明Bis-S传感器对于叶黄素具有良好的选择性和抗干扰性,且在比色法检测叶黄素方面具有一定应用前景。当Bis-S的浓度为1.00×10^(-5)mol·L^(-1)时,Bis-S体系荧光强度随叶黄素浓度的增加而减弱,检测范围为0~2.00×10^(-5)mol·L^(-1),线性定量检测范围为0~0.06μmol·L^(-1),检出限(2s/k)为1.21×10^(-9)mol·L^(-1);进行4个浓度水平的回收试验,叶黄素的回收率为94.0%~101%,测定值的相对标准偏差(n=6)为1.5%~4.1%。 展开更多
关键词 硫脲基桥联双四苯乙烯(bis-S) 叶黄素 传感器 荧光猝灭
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基于芳基桥联双β-二亚胺配体的金属铝配合物的合成与结构表征
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作者 李彩梅 毛贝贝 +1 位作者 肖长安 向丽 《广东化工》 CAS 2024年第7期34-36,共3页
β-二亚胺作为一类理想的含氮单阴离子非环戊二烯基配体,可以很好的稳定低价或配位不饱和的金属配合物,而桥联的双β-二亚胺配体要比单个β-二亚胺配体多个活性位点,会以更多的方式与金属配位,该类配合物表现出更高的催化活性和更加丰... β-二亚胺作为一类理想的含氮单阴离子非环戊二烯基配体,可以很好的稳定低价或配位不饱和的金属配合物,而桥联的双β-二亚胺配体要比单个β-二亚胺配体多个活性位点,会以更多的方式与金属配位,该类配合物表现出更高的催化活性和更加丰富的反应性。本文利用芳基桥联双β-二亚胺配体LH_(2)(L=[μ-(1,4-C_(6)H_(4))][N(Me)CH_(2)-CH_(2)NC(Me)CC(Me)HNDipp]_(2)^(2-),Dipp=2,6-(iPr)_(2)C_(6)H_(3))和4当量的三甲基铝反应,得到了相应的双核金属铝配合物LAl_(2)Me_(4)(1)。然后通过^(1)H NMR、^(13)C{^(1)H}NMR、红外光谱和单晶X-射线衍射对该配合物进行了结构表征。 展开更多
关键词 芳基桥联 双β-二亚胺配体 合成 结构表征
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Aluminum Complexes Stabilized by Piperazidine-Bridged Bis(phenolate) Ligands: Syntheses, Structures, and Applica- tion in the Ring-Opening Polymerization of ε-Caprolactone 被引量:3
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作者 李文艺 姚英明 +1 位作者 张勇 沈琪 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2012年第3期609-615,共7页
The synthesis and characterization of aluminum alkoxide and alkyl complexes stabilized by piperazidine- bridged bis(phenolate) ligands are described. Treatment of ligand precursors Hz[ONNO]^1 {Hz[ONNO]^1= 1,4-bis(2... The synthesis and characterization of aluminum alkoxide and alkyl complexes stabilized by piperazidine- bridged bis(phenolate) ligands are described. Treatment of ligand precursors Hz[ONNO]^1 {Hz[ONNO]^1= 1,4-bis(2-hydroxy-3-tert-butyl-5-methylbenzyl)piperazidine} and Hz[ONNO]2 {H2[ONNO]2=1,4-bis(2-hydroxy3,5-di-tert-butylbenzyl)piperazidine} with A1Et2(OCH2Ph) and A1Etz(OPr-i), which were generated in situ by the reactions of AIEt3 with equivalent of the corresponding alcohols, in a 1: 1 molar ratio in THF gave the corresponding aluminum alkoxide complexes [ONNO]IAI(OCH2Ph) (1) and [ONNO]2Al(OPr-i) (2), respectively. The reaction of H2[ONNO]^1 with A1Etz(OCHzPh) in a 1 : 2 molar ratio in THF afforded a mixture of monometallic aluminum ethyl complex [ONNO] 1A1Et (3) and complex 1, which can be isolated by stepwise crystallization. Similarly, Hz[ONNO]2 reacted with A1Etz(OPr-0 in a 1: 2 molar ratio in THF to give a mixture of aluminum ethyl complex [ONNO]2AlEt (4) and complex 2. Complexes 1 and 2 were also available via treatment of complexes 3 and 4 with 1 equiv, of benzyl alcohol and isopropyl alcohol, respectively. All of these complexes were fully characterized including X-ray structural determination. It was found that complexes 1 to 4 can initiate the ring-opening polymerization of e-caprolactone, and complexes 1 and 2 showed higher catalytic activity in comparison with com- plexes 3 and 4. 展开更多
关键词 aluminum piperazine-bridged bis(phenolate) ligand synthesis crystal structure polymerization ε-caprolactone
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The First Hybrid Wells-Dawson-type Polytungstate Monosupported by Cd-coordination Complex via Di-bridging O-atom 被引量:2
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作者 陈武华 张著森 +1 位作者 胡志彪 宓锦校 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2014年第10期1550-1559,共10页
Polyoxometalates(POMs) with Cd-coordination complexes acting as supporting units are rarely reported. The linkage of the supporting units with inorganic building block(polyanion) is generally established on termin... Polyoxometalates(POMs) with Cd-coordination complexes acting as supporting units are rarely reported. The linkage of the supporting units with inorganic building block(polyanion) is generally established on terminal O-atoms, but scarcely via bridging O-atoms. By introducing liquid small organic molecule(pyridine, C5NH5) as assistant "structure-directing agent", we obtained a novel organic-inorganic hybrid polytungstate,(Hpy)4[Cd(phen)2(P2W18O62)]·nH2O(1, n ≈ 3, py = pyridine, phen = 1,10-phenanthroline), under hydrothermal conditions. The single-crystal X-ray diffraction analysis shows that 1 is the first compound containing an asymmetric heteropolyanion, [Cd(phen)2(P2W18O62)]4–, a Wells-Dawson-type polyanion monosupported by Cd-coordination complex via di-bridging O-atoms. 展开更多
关键词 hybrid compound Wells-Dawson-type Cd-coordination complex monosupported structure bi-bridging O-atom
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Molecular Recognition of Bridged Bis(β-cyclodextrin)s Linked by Phenylenediseleno Tether on the Primary or Secondary Side with Fluorescent Dyes 被引量:1
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作者 李莉 何松 刘育 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2003年第7期964-969,共6页
A Novel β-cyclodextrin dimer,2,2′-o-phenylenediseleno-bridgedbis(β-cyclodextrin)(2),has been synthesized by reaction ofmono-[2-O-(p-tolylsulfonyl)]-β-cyclodextrin and poly(o-phenylenediselenide).The comple... A Novel β-cyclodextrin dimer,2,2′-o-phenylenediseleno-bridgedbis(β-cyclodextrin)(2),has been synthesized by reaction ofmono-[2-O-(p-tolylsulfonyl)]-β-cyclodextrin and poly(o-phenylenediselenide).The complexation stability constants(Ks)and Gibbs free energy changes(-ΔG°)of dimer 2 with fourfluorescence dyes,that is,ammonium 8-anilino-1-naphthalene-sulfonate(ANS),sodium 6-(p-toluidino)-2-naphthalenesul-fonate(TNS),Acridine Red(AR)and Rhodamine B(RhB)have been determined in aqueous phosphate buffer solution(pH=7.2,0.1 mol·L-1at 25℃ by means of fluorescence spec- 展开更多
关键词 oganoselenium-bridged bis(β-cyclodextrin) molecular recognition inclusion complexation binding mode
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基于Power BI桥梁监测数据可视化研究 被引量:3
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作者 刘文生 董泽堃 《价值工程》 2020年第13期235-237,共3页
在当前我国桥梁发展由建设向养护转移的重要背景下,因为长期积累的桥梁监测数据类型繁多、评价标准不同,导致数据可视化差、企业决策困难。以武汉市城市桥梁智慧管理平台桥梁监测数据为例,开展多源监测数据的标准化集成和基于Power BI... 在当前我国桥梁发展由建设向养护转移的重要背景下,因为长期积累的桥梁监测数据类型繁多、评价标准不同,导致数据可视化差、企业决策困难。以武汉市城市桥梁智慧管理平台桥梁监测数据为例,开展多源监测数据的标准化集成和基于Power BI的商业数据分析工具的可视化,对原始数据进行建模转换,实现异构数据源的集成,多维角度观察数据,通过可视化界面展开,提高桥梁数据展示能力,支持企业战略决策需求。 展开更多
关键词 桥梁监测数据 POWER bi 可视化
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Syntheses of bimetallic lanthanide bis(amido) complexes stabilized by bridged bis(guanidinate) ligands and their catalytic activity toward the hydrophosphonylation reaction of aldehydes and ketones
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作者 Kun Nie Chengwei Liu +1 位作者 Yong Zhang Yingming Yao 《Science China Chemistry》 SCIE EI CAS CSCD 2015年第9期1451-1460,共10页
A series of bimetallic lanthanide bis(amido) complexes stabilized by bridged bis(guanidinate) ligands {[(Me3Si)2N]2Ln[(RN)2-CN(CH2)2]}2 [R=iPr, Ln=Sm(1), Yb(2), Y(3); R=cyclohexyl(Cy), Ln=Sm(4), and Yb(5)] were synthe... A series of bimetallic lanthanide bis(amido) complexes stabilized by bridged bis(guanidinate) ligands {[(Me3Si)2N]2Ln[(RN)2-CN(CH2)2]}2 [R=iPr, Ln=Sm(1), Yb(2), Y(3); R=cyclohexyl(Cy), Ln=Sm(4), and Yb(5)] were synthesized through the metathesis reactions of {Ln(μ-Cl)[N(Si Me3)2]2(THF)}2(Ln=Sm, Yb, Y) with lithium guanidinate {Li[(RN)2CN(CH2)2]}2(R=iPr, Cy), the latter of which was generated in situ by the reaction of carbodiimides with lithium amides. Complexes 1–5 were well characterized by elemental analyses, IR spectra, and(for Complex 3) NMR spectroscopy. The solid-state molecular structures of all of the complexes were determined by single-crystal X-ray analyses with the exception of Complex 3, which showed similar unsolvated centrosymmetric dinuclear structures. Each of the lanthanide centers is four-coordinated with two nitrogen atoms from a guanidinate ligand and two nitrogen atoms from two amido groups. The piperazidine rings adopt chair conformations in all cases. These organolanthanide complexes were found to be efficient catalysts for the hydrophosphonylation reaction of various aldehydes and unactivated ketones and to afford ?-hydroxyphosphonates in high yields under low catalyst loading(0.1 mol%) in a short reaction time. 展开更多
关键词 bimetallic lanthanide complex bridged bis(guanidinate) ligand hydrophosphonylation reaction aldehyde ketone
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