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掺杂LiF的ESR谱和ENDOR谱研究 被引量:2
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作者 孙福印 焦玲 +1 位作者 武建伟 杨正红 《波谱学杂志》 CAS CSCD 1993年第4期405-412,共8页
LiF:Mg,Cu热释光(TL)磷光体在y辐照后产生F^0顺磁中心,其g因子为g_(xx)=2.0030,g_(yy)=2.0450,g_(zz )=2.0251,裂分为 A_(xx)=511.04G,A_(yy)=505.42G,A_(zz)=507.26G。F^0中心的浓度随Mg^(++)浓度的增加而下降。磷光体的ENDOR谱显示F^... LiF:Mg,Cu热释光(TL)磷光体在y辐照后产生F^0顺磁中心,其g因子为g_(xx)=2.0030,g_(yy)=2.0450,g_(zz )=2.0251,裂分为 A_(xx)=511.04G,A_(yy)=505.42G,A_(zz)=507.26G。F^0中心的浓度随Mg^(++)浓度的增加而下降。磷光体的ENDOR谱显示F^0中心附近有铜核存在。照射前和照射后24h测量均未发现Cu^(++)的ESR谱,表明铜是以Cu^+形式掺入的,照射并未引起Cu^+离子化合价的改变。LiF:Mg,Cu ,P在y辐照前具有轴对称的Cu^(++)离子的ESR谱,辐照后产生了O^-空穴中心和PO_3^(2-)自由基,改变了Cu^(++)的环境,使Cu^(++)的谱发生变化。这些结果对研究Cu和P在该磷光体的热释发光中的作用具有参考意义。 展开更多
关键词 发光粉 氟化锂 ESR ENDOR
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Colonoscopy attachments for the detection of precancerous lesions during colonoscopy:A review of the literature 被引量:5
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作者 Paraskevas Gkolfakis Georgios Tziatzios +2 位作者 Eleftherios Spartalis Ioannis S Papanikolaou Konstantinos Triantafyllou 《World Journal of Gastroenterology》 SCIE CAS 2018年第37期4243-4253,共11页
Although colonoscopy has been proven effective in reducing the incidence of colorectal cancer through the detection and removal of precancerous lesions, it remains an imperfect examination, as it can fail in detecting... Although colonoscopy has been proven effective in reducing the incidence of colorectal cancer through the detection and removal of precancerous lesions, it remains an imperfect examination, as it can fail in detecting up to almost one fourth of existing adenomas. Among reasons accounting for such failures, is the inability to meticulously visualize the colonic mucosa located either proximal to haustral folds or anatomic curves, including the hepatic and splenic flexures. In order to overcome these limitations, various colonoscope attachments aiming to improve mucosal visualization have been developed. All of them-transparent cap, Endocuff, Endocuff Vision and Endorings-are simply mounted onto the distal tip of the scope. In this review article, we introduce the rationale of their development, present their mode of action and discuss in detail the effect of their implementation in the detection of lesions during colonoscopy. 展开更多
关键词 ADENOMA DETECTION RATE ADENOMA MISS RATE COLONOSCOPY Cup Endocuff Endocuff Vision endorings
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一个稳定自由基的酮-烯醇互变异构——三(2-去氧-2-L-抗坏血酸基)胺自由基负离子的ESR和ENDOR研究
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作者 吴隆民 刘中立 +2 位作者 王丽娟 刘有成 程金龙 《高等学校化学学报》 SCIE EI CAS 1988年第7期692-695,共4页
在pH8.95的缓冲溶液中氧化三(2-去氧-2-L-抗坏血酸基)胺得一对应的自由基负离子,对其进行了ESR和ENDOR研究。结果表明该自由基负离子在溶液中以酮-烯醇互变异构体存在,这可能是在稳定自由基中发现存在酮-烯醇互变异构平衡的首例。
关键词 酮-烯醇互变异构 ESR ENDOR
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基于直接数字合成技术的电子自旋-核自旋双共振实验射频信号源设计 被引量:1
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作者 徐挽杰 王梓翔 +3 位作者 徐南阳 荣星 苏吉虎 杜江峰 《波谱学杂志》 CAS CSCD 北大核心 2011年第4期471-478,共8页
为了满足脉冲式电子顺磁共振谱仪中电子自旋-核自旋双共振模块的需要,利用直接数字合成器设计并制作了射频信号源.该部件产生的射频脉冲具备对频率、幅度和相位快速精确调制的能力,对原子核自旋有较强操控能力.
关键词 电子自旋-核自旋双共振(ENDOR) 直接数字合成
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二(2-羟基苯乙酮肟)^(63)Cu(Ⅱ)配合物中^(14)N核的ENDOR研究 被引量:1
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作者 徐元植 陈德余 +5 位作者 程朝荣 宫本量 大庭裕■ 岩泉正基 周澄明 陈耀焕 《中国科学(B辑)》 CSCD 北大核心 1992年第4期337-344,共8页
本文用定向选择的方法,研究了在20K下测定的14N-63Cu-HAP的DMSO/EtOH(5:1)冷冻溶液的ENDOR谱,精确测得配体^(14)N核的各向异性超超精细耦合张量值,各种不同~1H核的超超精细耦合张量值和^(14)N核的四极矩耦合张量值。^(14)N核超超精细耦... 本文用定向选择的方法,研究了在20K下测定的14N-63Cu-HAP的DMSO/EtOH(5:1)冷冻溶液的ENDOR谱,精确测得配体^(14)N核的各向异性超超精细耦合张量值,各种不同~1H核的超超精细耦合张量值和^(14)N核的四极矩耦合张量值。^(14)N核超超精细耦合张量值与前文^([10])的数值比较表明,前文的波谱解析,方法是合理的,数据是可靠的。 展开更多
关键词 ENDOR ESR 铜配合物 氮14核
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ENDOR AND ESR STUDIES OF RADICALS FORMED IN FRIEDEL-CRAFTS REACTIONS
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作者 桑鸿 汪汉卿 +4 位作者 陈涛 刘旭勤Center of Analysis and Research East China University of Chemical Technology Shanghai 200237 PRC 《Science China Chemistry》 SCIE EI CAS 1991年第11期1296-1303,共8页
The present study deals with the study of some Friedel-Crafts alkylating system and the accurate measurement of hyperfine coupling constants by ESR and ENDOR techniques. The results indicate that the observed ESR spec... The present study deals with the study of some Friedel-Crafts alkylating system and the accurate measurement of hyperfine coupling constants by ESR and ENDOR techniques. The results indicate that the observed ESR spectra are due to polycyclic aromatic radical cations formed from their parent hydrocarbons.It is suggested that benzyl halides produced in the Friedel-Crafts alkylating reaction undergo Scholl condensation reaction to give polycyclic aromatic hydrocarbons, which were converted into the corresponding polycyclic aromatic radical cations in the presence of aluminum chloride. 展开更多
关键词 RADICAL CATIONS ESR ENDOR FRIEDEL-CRAFTS reactions.
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^(14)N ENDOR Study on Bis(2-Hydroxylphenyl Ketoxime)-^(63)Cu(Ⅱ) Complex
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作者 徐元植 陈德余 +5 位作者 程朝荣 宫本量 大庭裕范 岩泉正基 周澄明 陈耀焕 《Science China Chemistry》 SCIE EI CAS 1993年第9期1052-1060,共9页
The ENDOR spectrum of ^(14)N-^(63)Cu-HAP complex in DMSO/EtOH (5:1) freezing solution at 20 K has been studied using orientational selective method in this paper. The anisotropic superhyperfine coupling tensor and qus... The ENDOR spectrum of ^(14)N-^(63)Cu-HAP complex in DMSO/EtOH (5:1) freezing solution at 20 K has been studied using orientational selective method in this paper. The anisotropic superhyperfine coupling tensor and qusdrupole coupling tensor of ligand ^(14)N nucleus, and the superhyperfine coupling tensor of various ~1H nuclei have been measured precisely. Comparing the superhyperfine coupling tensor of ^(14)N-nucleus with previous work shows that the analytical method of spectrum is reasonable and the data are reliable in our previous work. 展开更多
关键词 ENDOR ESR bis(2-hydroxylphenyl ketoxime) ~4N ^(63)Cu complex.
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Endoring自撑拉钩辅助微创小切口前路单节段减压固定融合治疗Denis B型胸腰椎爆裂骨折
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作者 张哲 田晓东 《中国医疗器械信息》 2021年第18期29-30,共2页
目的:评估Denis B型胸腰椎爆采取裂前路单节段减压固定融合治疗骨折辅助应用Endoring自撑拉钩疗效。方法:回顾性分析2016年1月~2019年12月收入Denis B型胸腰椎爆裂骨折患者19例,对患者临床一般资料进行分析,所有患者予以Endoring自撑拉... 目的:评估Denis B型胸腰椎爆采取裂前路单节段减压固定融合治疗骨折辅助应用Endoring自撑拉钩疗效。方法:回顾性分析2016年1月~2019年12月收入Denis B型胸腰椎爆裂骨折患者19例,对患者临床一般资料进行分析,所有患者予以Endoring自撑拉钩辅助联合前路单节段减压固定融合治疗,对其疗效进行分析。结果:与术前比较,术后3个月、术后6个月、术后12个月患者VAS、椎间高度及Cobb角得到显著改善,差异显著(P<0.05)。结论:对临床Denis B型胸腰椎爆裂骨折,开展前路单节段减压固定融合术式期间,辅助予以Endoring自撑拉钩,可减少创伤,可充分减压椎管提高植骨融合率,作为一类安全、有效术式。 展开更多
关键词 Endoring自撑拉钩 前路单节 Denis B型胸腰椎爆裂骨折 治疗
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