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Ag(Ⅰ)与氯苯基苯并咪唑配合物的合成、圆二色性和荧光性质
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作者 王卓渊 林香凤 《化工技术与开发》 CAS 2024年第1期8-11,39,共5页
本文合成了Ag(Ⅰ)与2-(o-氯苯基)苯并咪唑(OCBM)的配合物,采用元素分析、质谱、UV、IR、摩尔电导率等手段进行了表征。圆二色性研究发现,配合物在199nm处呈正科顿效应,而在208nm和247nm处呈负科顿效应。荧光性质研究表明,配合物的特征... 本文合成了Ag(Ⅰ)与2-(o-氯苯基)苯并咪唑(OCBM)的配合物,采用元素分析、质谱、UV、IR、摩尔电导率等手段进行了表征。圆二色性研究发现,配合物在199nm处呈正科顿效应,而在208nm和247nm处呈负科顿效应。荧光性质研究表明,配合物的特征荧光发射峰出现在601nm和613nm处,荧光寿命τ601和τ613分别为0.40ns和0.35ns。Ag(Ⅰ)配合物可发射橙色荧光和红色荧光,是良好的荧光材料。 展开更多
关键词 2-(o-氯苯基)苯并咪唑 ag(Ⅰ)配合物 合成 圆二色性 荧光性质
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Expanded Follicle-Sulcus-Crack Complex Is an Early Warning Sign of Facial Skin Aging: Improvement by Application of Galactomyces Ferment Filtrate-Containing Skin Product
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作者 Kukizo Miyamoto Bandara Dissanayake +3 位作者 Shenal Wanigasekara Keisuke Fujii Xianghong Yan Masutaka Furue 《Journal of Cosmetics, Dermatological Sciences and Applications》 2023年第2期91-106,共16页
Background: Wrinkles, pigmented spots, and roughness are representative parameters reflecting facial skin aging. Sulci cutis connecting to follicular orifices frequently form perifollicular cracks, which join together... Background: Wrinkles, pigmented spots, and roughness are representative parameters reflecting facial skin aging. Sulci cutis connecting to follicular orifices frequently form perifollicular cracks, which join together adjacent sulci. This follicle-sulcus-crack complex (FSCC) is exacerbated by dehydration. Purpose: Although dehydration is associated with facial skin aging, FSCC’s implications in facial skin aging remain unresolved. Method: We measured facial skin parameters in 1999 and 2010 in 108 Japanese women, and in 2006 and 2016 in 182 Chinese women. We addressed whether expansion of FSCC is associated with other skin aging parameters. We also examined whether skin moisturizer can reverse the expanded FSCC. Results: In both clinical studies, FSCC severity as well as wrinkles, spots, and roughness significantly deteriorated with age. Notably, FSCC significantly increased as early as in subjects in their 20s, whereas wrinkles, spots, and roughness became conspicuous in those in their 40s or older. Moreover, subjects with more severe FSCC in the initial measurement exhibited significantly worse wrinkles, spots, and roughness in the second measurement a decade later. Dehydration was significantly correlated with expanded FSCC. Furthermore, FSCC expansion was reversed after appropriate moisturization by daily application of Galactomyces ferment filtrate (GFF)-containing skincare product (SK-II Skin Power Cream) for 4 weeks in 37 women. Conclusion: The expanded FSCC is likely to be an early indicator of facial skin aging. Appropriate moisturization may reduce FSCC formation and decelerate facial skin aging. 展开更多
关键词 Facial Skin aging Follicle-Sulcus-Crack complex DEHYDRATION Hyperpigmented Spot WRINKLE Galactomyces Ferment Filtrate
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Syntheses, Crystal Structures and Properties of Two New W-Ag 1D Chain Complexes: [W_2Ag_2S_8·Ca(DMF)_6]_n and [WAgS_4·Na(DMF)_3]_n 被引量:1
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作者 LIYa-Min XIASheng-Qing ZHANGJian-Jun WUXin-Tao WANGLong-Sheng DUWen-Xin HUSheng-Min 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2005年第6期716-722,共7页
Two new complexes, [W2Ag2S8?Ca(DMF)6]n 1 and [WAgS4?Na(DMF)3]n 2, have been synthesized and characterized. Single-crystal X-ray analyses show both 1 and 2 have {WAgS4}n anion linear chains, but 1 has a discrete [Ca(DM... Two new complexes, [W2Ag2S8?Ca(DMF)6]n 1 and [WAgS4?Na(DMF)3]n 2, have been synthesized and characterized. Single-crystal X-ray analyses show both 1 and 2 have {WAgS4}n anion linear chains, but 1 has a discrete [Ca(DMF)6]2+ cation while 2 is a linear chain. UV-Visible-Near-IR spectroscopy data show that the bandgaps of the two complexes are 1.86 and 1.99 eV, respectively. Electrical conductivity measurements reveal the conductivities of 1 and 2 are 10?7 and 10?8 Scm?1, respectively and they exhibit thermally activated temperature depen- dence, which may be attributed to semiconductors. 展开更多
关键词 W/ag/S complexes linear chain conductivity
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Synthesis, DNA-binding, and Photocleavage of 2,3-Di-2-pyridylquinoxaline-silver(Ⅰ) Complex 被引量:2
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作者 WANG Xiu-li FANG Jia-ni BI Yan-feng LIN Hong-yan LIU Guo-cheng 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2008年第1期15-19,共5页
A new dinuclear complex, [Ag(L)(CH3CN)]2(ClO4)2·2H2O(L=2,3-di-2-pyridylquinoxaline), was prepared and characterized by elemental analyses, IR spectroscopy, and single-crystal X-ray diffraction analyses. T... A new dinuclear complex, [Ag(L)(CH3CN)]2(ClO4)2·2H2O(L=2,3-di-2-pyridylquinoxaline), was prepared and characterized by elemental analyses, IR spectroscopy, and single-crystal X-ray diffraction analyses. The interaction of the complex with calf thymus DNA(CT-DNA) was investigated by absorption, fluorescence spectroscopies, and viscosity measurement. The results suggested that the complex was bound to DNA via an intercalative mode. The intrinsic binding constant value Kb was found to be approximately 1.48×10^3 L·mol^-1. Moreover, the Ag(I) complex could cleave the plasmid pUC19 DNA from the supercoiled Form Ⅰto the nicked FormⅡ under irradiation at 365 nm. 展开更多
关键词 DNA ag-Polypyridyl complex Interaction Fluorescence CLEAVagE
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Synthesis, Crystal Structure and Photoluminescence of a Three-coordinate Ag(Ⅰ) Complex 被引量:1
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作者 滕腾 陈进 +2 位作者 陈旭林 余荣民 卢灿忠 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2014年第11期1661-1665,共5页
A three-coordinate Ag(I) complex, [Ag(Mepzpy)(PAr3)]BF4·H2O(1, Mepzpy = 3-methyl-1-(2-pyridyl)pyrazole, PAr3 = tri(o-tolyl)phosphine), was synthesized from the reaction of Ag(CH3CN)4BF4, PAr3 and Me... A three-coordinate Ag(I) complex, [Ag(Mepzpy)(PAr3)]BF4·H2O(1, Mepzpy = 3-methyl-1-(2-pyridyl)pyrazole, PAr3 = tri(o-tolyl)phosphine), was synthesized from the reaction of Ag(CH3CN)4BF4, PAr3 and Mepzpy in CH3 CN at room temperature. The compound was characterized by UV-vis, NMR and X-ray single-crystal structure analysis. It crystallizes in triclinic space group P1 with a = 10.2251(5), b = 10.6014(5), c = 15.7012(5) A, α = 92.963(3), β = 92.641(3), γ = 114.647(4)°, V = 1540.6(1)A 3, Z = 2, Mr = 676.24, Dc = 1.458 g/cm3, F(000) = 688, μ = 6.187 mm^-1, GOOF = 1.038, the final R = 0.0530 and wR = 0.1493 for 6371 observed reflections with I 〉 2σ(I). Compound 1 is ionic. It is composed of a BF4- anion and a [Ag(Mepzpy)(PAr3)]+ cation. The Ag(I) ion adopts a distorted trigonal pyramidal coordination geometry defined by two nitrogen atoms and a phosphorous atom. The complex emits blue luminescence with maximum peaks at 470 nm in solid state at room temperature. 展开更多
关键词 mononuclear ag(I) complex crystal structure THREE-COORDINATE PHOSPHORESCENCE
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Age-related changes in proprioception of the ankle complex across the lifespan 被引量:1
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作者 Nan Yang Gordon Waddington +1 位作者 Roger Adams Jia Han 《Journal of Sport and Health Science》 SCIE 2019年第6期548-554,共7页
Background:Ankle complex proprioceptive ability,needed in active human movement,may change from childhood to elderly adulthood;however,its development across all life stages has remained unexamined.The aim of the pres... Background:Ankle complex proprioceptive ability,needed in active human movement,may change from childhood to elderly adulthood;however,its development across all life stages has remained unexamined.The aim of the present study was to investigate the across-the-lifespan trend for proprioceptive ability of the ankle complex during active ankle inversion movement.Methods:The right ankles of 118 healthy right-handed participants in 6 groups were assessed:children(6-8 years old),adolescents(13-15 years old),young adults(18-25 years old),middle-aged adults(35-50 years old),old adults(60-74 years old),and very old adults(75-90 years old).While the participants were standing,their ankle complex proprioception was measured using the Active Movement Extent Discrimination Apparatus.Results:There was no significant interaction between the effects of age group and gender on ankle proprioceptive acuity(F(5,106)=0.593,p=0.705,η_p^2=0.027).Simple main effects analysis showed that there was a significant main effect for age group(F(5,106)=22.521,p<0.001,η_p^2=0.515)but no significant main effect for gender(F(1,106)=2.283,p=0.134,η_p^2=0.021)between the female(0.723±0.092,mean±SD)and the male(0.712±0.083)participants.The age-group factor was associated with a significant linear downward trend in scores(F(1,106)=10.584,p=0.002,η_p^2=0.091)and a strong quadratic trend component(F(1,106)=100.701,p<0.001,η_p^2=0.480),producing an asymmetric inverted-U function.Conclusion:The test method of the Active Movement Extent Discrimination Apparatus is sensitive to age differences in ankle complex proprioception.For proprioception of the ankle complex,young adults had significantly better scores than children,adolescents,old adults,and very old adults.The middle-aged group had levels of ankle proprioceptive acuity similar to those of the young adults.The scores for males and females were not significantly different.Examination of the range of the scores in each age group highlights the possible level that ankle complex movement proprioceptive rehabilitation can reach,especially for those 75-90 years of age. 展开更多
关键词 agING ANKLE complex Development Motor control PROPRIOCEPTION
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Differential Sensibility of Information Processing Capacity with Age: Effects of Physical Activity and Task Complexity 被引量:1
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作者 Khadher Souha Abedelmalek Salma +1 位作者 Grira Youssef Bertsch Jean 《Open Journal of Medical Psychology》 2013年第1期1-6,共6页
Study aim: Movement control systems are altered by the aging process. Numerous researches have explained the changes that occur with aging, and many of those changes are related to central nervous system (CNS) effects... Study aim: Movement control systems are altered by the aging process. Numerous researches have explained the changes that occur with aging, and many of those changes are related to central nervous system (CNS) effects. This article evaluates the impact of age, the practice of regular physical activity, and the task complexity on decision-making ability. Methods: 120 healthy male subjects volunteered to participate in this study. They included 60 young adults (i.e., 30 sedentary and 30 active) (age: 24.35 ± 2.82 years), as well as 60 older adults (age: 66.42 ± 4.06 years) (i.e., 30 sedentary and 30 active). They performed two types of tasks (i.e., simple and complex) to measure reaction time (RT). Subjects perceive visual stimuli through the computer screen. Results: Our results showed that older active subjects have lower RT than older sedentary subjects (p i.e., simple or complex). Conclusions: Physical activity improves the decision making ability in older subjects. 展开更多
关键词 aging-Physical Activity-complexity-Decision MAKING
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U-Pb Age and Hf Isotope Study of Detrital Zircons from the Wanzi Supracrustals:Constraints on the Tectonic Setting and Evolution of the Fuping Complex,Trans-North China Orogen 被引量:12
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作者 Xiaoping XIA Min SUN +5 位作者 Guochun ZHAO WU Fuyuan XU Ping Jian ZHANG Yanhong HE ZHANG Jiheng 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2006年第6期844-863,共20页
Located in the middle segment of the Trans-North China Orogen, the Fuping Complex is considered as a critical area in understanding the evolution history of the North China Craton (NCC). The complex is composed of v... Located in the middle segment of the Trans-North China Orogen, the Fuping Complex is considered as a critical area in understanding the evolution history of the North China Craton (NCC). The complex is composed of various high-grade and multiply deformed rocks, including gray gneiss, basic granulite, amphibolite, fine-grained gneiss and marble, metamorphosed to upper amphibolite or granulite facies. It can be divided into four rock units: the Fuping TTG gneisses, Longquanguan augen gneisses, Wanzi supracrustals, and Nanying granitic gneisses. U-Pb age and Hf isotope compositions of about 200 detrital zircons from the Wanzi supracrustals of the Fuping Complex have been analyzed. The data on metamorphic zircon rims give ages of 1.82-1.84 Ga, corresponding to the final amalgamation event of the NCC, whereas the data for igneous zircon cores yield two age populations at -2.10 and -2.51 Ga, with some inherited ages scattering between 2.5 and 2.9 Ga. These results suggest that the Wanzi supracrustals were derived from the Fuping TTG gneisses (-2.5 Ga) and the Nanying granitic gneisses (2.0-2.1 Ga) and deposited between 2.10 and 1.84 Ga. All zircons with -2.51 Ga age have positive initial εHf values from +1.4 to +10.9, suggesting an important crustal growth event at -2.5 Ga through the addition of juvenile materials from the mantle. The Hf isotope data for the detrital zircons further imply that the 2.8 Ga rocks are important components in the lower crust, which is consistent with a suggestion from Nd isotope data for the Eastern Block. The zircons of 2.10 Ga population have initial εHf values of-4.9 to +6.1, interpreted as mixing of crustal re-melt with minor juvenile material contribution at 2.1 Ga. These results are distinct from that for the Western Block, supporting that the Fuping Complex was emplaced in a tectonic active environment at the western margin of the Eastern Block. 展开更多
关键词 detrital zircons U-Pb age and Hf isotope Fuping complex North China Craton
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Synthesis and Crystal Structure of a Novel Complex [Ag(NIT3Py)_3]·(ClO_4)(H_2O)
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作者 ZHANGChen-Xia LIAODai-Zheng +1 位作者 JIANGZong-Hui YANShi-Ping 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2005年第6期625-628,共4页
A novel complex [Ag(NIT3Py)3]?(ClO4)(H2O) has been synthesized and structurally characterized by X-ray diffraction method. It crystallizes in the rhombohedral system, space group R 3 with a = 15.8227(17), b = 15.8227(... A novel complex [Ag(NIT3Py)3]?(ClO4)(H2O) has been synthesized and structurally characterized by X-ray diffraction method. It crystallizes in the rhombohedral system, space group R 3 with a = 15.8227(17), b = 15.8227(17), c = 31.445(3) ?, γ = 120°, V = 6817.8(12) ?3, Dc = 1.370 g/cm3, Z = 6, μ = 0.566 mm-1, Mr = 937.18, F(000) = 2916, R = 0.0715, wR = 0.2115 and GOF = 1.086. The structure consists of Ag(NIT3Py)3+ cation moiety, one water molecule and one perchloric ion. The Ag(I) ion is in a trigonal planar coordination environment formed by three nitrogen atoms from three NIT3Py ligand molecules. 展开更多
关键词 crystal structure nitronyl nitroxide radical ag(I) complex MagNETISM ferromagnetic interactions
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Synthesis, Characterization and Crystal Structure of a Dinuclear Silver(I) Complex: [AgL(NO_3)]_2 (L= 2-Acetamido-5-methyl-1,3,4-thiadiazole)
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作者 张玉霞 宋世林 +1 位作者 吕艳阳 薛灵芬 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2006年第1期45-48,共4页
The title complex [AgL(NO3)]2 1, where L = 2-acetamido-5-methyl-1,3,4-thiadiazole, was prepared from the reaction of 2-acetamido-5-methyl-1,3,4-thiadiazole with AgNO3 at room temperature and its structure has been d... The title complex [AgL(NO3)]2 1, where L = 2-acetamido-5-methyl-1,3,4-thiadiazole, was prepared from the reaction of 2-acetamido-5-methyl-1,3,4-thiadiazole with AgNO3 at room temperature and its structure has been determined by single-crystal X-ray diffraction. The crystal is of monoclinic, space group P2t/c with a = 12.5454(8), b = 11.9672(12), c = 6.8925(6) A, β = 98.468(2)°. V= 1023.51(15) A^3, Mr= 3127.08, Dc = 2.123 g/cm^3, Z= 4, μ(MoKoσ) = 2.174 mm^-1, F(000) = 640, R = 0.0259 and wR = 0.0580 for 1787 observed reflections with I 〉 2σ(I). Complex 1 self-assembls into a quasi-three-dimensional network consisting of adjacent dimers through intermolecular Ag...O weak interactions. 展开更多
关键词 SYNTHESIS crystal structure 2-acetamido-5-methyl-1 3 4-thiadiazole ag(Ⅰ) complex weak interactions
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New detrital zircon U-Pb ages from BIF-related metasediments in the Ntem Complex (Congo craton) of southern Cameroon, West Africa 被引量:5
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作者 Nelson N. Chombong Emmanuel C. Suh Charles D. C. Ilouga 《Natural Science》 2013年第7期835-847,共13页
Banded Iron Formations (BIFs) were formed by contemporaneous events of active sediments supply and the venting of a hydrothermal fluid source at the Mid-Ocean-Ridge. BIFs within the Ntem Complex at the northern edge o... Banded Iron Formations (BIFs) were formed by contemporaneous events of active sediments supply and the venting of a hydrothermal fluid source at the Mid-Ocean-Ridge. BIFs within the Ntem Complex at the northern edge of the Congo Craton are intercalated with metasandstones and siltstones. SHRIMP U-Pb analysis on detrital zircons obtained from these metasediments gave variable ages from over 3000 Ma to 1000 Ma with the maximum age of deposition clustered around 1200 Ma and the peak of deposition at 1800 Ma. This age range suggested that the sub-basin was opened sometime in the Archean and remained active up till the Neoproterozoic. Zircons with Archean ages have a provenance linked to the charnockitic suite and the high-K granites within the Ntem Complex. The Paleoproterozoic ages are attributed to clastic inputs from the neigbouring Nyong Series west of the Ntem Complex. Also the peak of deposition in the Proterozoic could probably be explained by the globally recognized intense crust-forming processes in the Early Proterozoic time. The provenance of the younger Neoproterozoic ages is tied to various lithologies within the northern mobile belts of the Adamawa-Yade massifs and correlates with Neoproterozoic sedimentation ages in the Yaoundé, Lom and Poli series. The Neoproterozoic ages obtained are comparable to those obtained from metasediments of the Amazonian Craton and provide evidence of Pre-Gondwana assemblage of the Congo and the S?o Francisco Cratons. 展开更多
关键词 BIFs METASEDIMENTS Ntem complex SHRIMP U-PB age DETRITAL ZIRCONS
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SHRIMP Zircon U-Pb Dating of the Tongshi Magmatic Complex in Western Shandong and Its Geological Implications 被引量:1
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作者 HU Huabin MAO Jingwen +4 位作者 LIU Dunyi NIU Shuyin WANG Yanbin LI Yongfeng SHI Ruruo 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2005年第4期491-496,共6页
The SHRIMP U-Pb zircon dating result of the Tongshi magmatic complex in western Shandong is presented in this paper. The Tongshi magmatic complex comprises fine-grained porphyritic diorite and syenitic porphyry. Eight... The SHRIMP U-Pb zircon dating result of the Tongshi magmatic complex in western Shandong is presented in this paper. The Tongshi magmatic complex comprises fine-grained porphyritic diorite and syenitic porphyry. Eighteen analyses for fine-grained porphyritic diorite gave two concordia ages, in which ten analyses constitute the young age group, giving ^206Pb/^238U ages ranging from 167.9 Ma to 183 Ma with a weighted mean age of 175.7±3.8 Ma, and the other eight yielded ^207Pb/^206Pb ages of 2502 Ma to 2554 Ma with a weighted mean 2518±11 Ma. Two analyses for syenitic porphyry gave ages of 2485 Ma and 2512 Ma, respectively. The age of 175.7±3.8 Ma indicates that the crystallization of the Tongshi magmatic complex occurred in the Middle Jurassic, whereas that of 2518±11 Ma is interpreted as the age of inherited magmatic zircons in the Neoarchean Wutai period. 展开更多
关键词 ZIRCON SHRIMP U-Pb dating age Middle Jurassic Tongshi magmatic complex western Shandong
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Multistage Extension and Age Dating of the Xiaoqinling Metamorphic Core Complex,Central China 被引量:23
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作者 ZHANG Jinjiang ZHENG Yadong 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 1999年第2期139-147,共9页
Abstract There are two extensional systems in the Xiaoqinling metamorphic core complex (XMCC). One is the detachment fault system developed along the peripheries of the XMCC, which extended in an ESE-WNW direction and... Abstract There are two extensional systems in the Xiaoqinling metamorphic core complex (XMCC). One is the detachment fault system developed along the peripheries of the XMCC, which extended in an ESE-WNW direction and whose upper plate moved towards the WNW. The other extensional system includes the retrograde shear zones and normal faults developed within the XMCC, which represent the collapse of the XMCC. Ar-Ar and K-Ar dating shows that the extension of the detachment fault system continued from 135 to 123 Ma, i.e. in the late stage of its evolution at about 127 Ma. The collapse represented by the extensional system within the XMCC was operative during 120–106 Ma, and its main activity occurred about 116 Ma ago. These suggest that the XMCC experienced two extensional stages in its evolution, i.e., the syn-orogenic regional extension and post-orogenic collapse extension. 展开更多
关键词 Xiaoqinling metamorphic core complex (XMCC) MULTISTagE EXTENSION detachment fault COLLAPSE agES
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SHRIMP Zircon U-Pb Ages of the Wajilitag Igneous Complex: Constraints on the Origin of A-type Granitoids in the Tarim Large Igneous Province, NW China 被引量:1
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作者 CAO Jun TAO Jihua WANG Xuan 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2017年第6期2318-2320,共3页
Objective Large igneous provinces (LIPs) are sites of spatially contiguous, rapidly emplaced magmatic rocks, which represent the physical and chemical transfer of material from the mantle to the crust. Exposed with... Objective Large igneous provinces (LIPs) are sites of spatially contiguous, rapidly emplaced magmatic rocks, which represent the physical and chemical transfer of material from the mantle to the crust. Exposed within some continental LIPs are felsic and rnafic plutonic and volcanic rocks. Although their volumes are minor compared to the flood basalts, the plutonic rocks of continental LIPs are often associated with economic deposits of precious metals. Within the Permian Tarim LIP of NW China, there are at least two layered ultramafic-mafic intrusions (e.g. Wajilitag and Piqiang) contain economically important Fe- Ti-V oxide deposits. Spatially associated with these layered ultramafic-mafic intrusions are syenitic and granitic plutons, which have chemical characteristics of A- type granitoids. 展开更多
关键词 SHRIMP Zircon U-Pb ages of the Wajilitag Igneous complex Constraints on the Origin of A-type Granitoids Tarim Large Igneous Province NW China
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锌离子络合法快速分离纯化荞麦壳黄酮及其抗AGEs活性 被引量:1
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作者 王玥 刘子琦 +5 位作者 聂萌滋 姜鑫 李鹏程 闫梦华 朴春红 肖盛元 《中国食品学报》 EI CAS CSCD 北大核心 2023年第10期167-177,共11页
研究锌离子络合法快速分离纯化荞麦壳黄酮工艺,并评价纯化组分对晚期糖基化终末产物(AGEs)生成的抑制活性。根据络合转化率和络合强度,将荞麦壳黄酮提取物(BHF)经过二次锌离子络合,分别获得荞麦壳黄酮中间提取物(IBHF)和荞麦壳高黄酮组... 研究锌离子络合法快速分离纯化荞麦壳黄酮工艺,并评价纯化组分对晚期糖基化终末产物(AGEs)生成的抑制活性。根据络合转化率和络合强度,将荞麦壳黄酮提取物(BHF)经过二次锌离子络合,分别获得荞麦壳黄酮中间提取物(IBHF)和荞麦壳高黄酮组分(HBHF)。采用Box-Behnken响应曲面分析法优化获得IBHF组分的最佳工艺参数:乙酸锌与样品质量比2∶1,乙醇体积分数30%,氨水体积分数0.05%,室温反应10 min。在该条件下络合转化率为97.44%。IBHF组分经过二次锌离子络合,分离获得HBHF组分,其总黄酮含量为57.08 g RE/100 g(三氯化铝-乙酸盐比色法),其纯度比分离纯化前提高了6.64倍。高效液相色谱分析(HPLC)表明,HBHF组分含有异荭草素、牡荆素、异牡荆素、芦丁、山奈酚-3-O芸香糖苷5种主要黄酮,其中芦丁占比62.34%。HBHF组分表现出良好的抗AGEs活性,在质量浓度为200μg/mL时,Glu-BSA体系的中的AGEs抑制率为63.16%,MGO-BSA体系中的AGEs抑制率为42.98%,抑制率均显著优于阳性对照氨基胍。 展开更多
关键词 锌离子络合法 二次锌离子络合 荞麦壳黄酮 晚期糖基化终末产物(agEs)
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辽东地区赛马碱性杂岩锆石U-Pb年龄、Hf同位素组成及其对构造背景的制约
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作者 杨凤超 宋运红 +2 位作者 胥嘉 顾玉超 杨宏智 《地质通报》 CAS CSCD 北大核心 2024年第1期76-85,共10页
通过LA-ICP-MS测得辽宁赛马地区浅肉红色霞霓正长岩中的锆石U-Pb年龄为225.8±1.9 Ma,赛马碱性杂岩的侵位时代为晚三叠世。地球化学分析表明,霞霓正长岩SiO_(2)含量为55.87%~60.88%,Na_(2)O为0.41%~5.32%,Al_(2)O_(3)为17.81%~19.53... 通过LA-ICP-MS测得辽宁赛马地区浅肉红色霞霓正长岩中的锆石U-Pb年龄为225.8±1.9 Ma,赛马碱性杂岩的侵位时代为晚三叠世。地球化学分析表明,霞霓正长岩SiO_(2)含量为55.87%~60.88%,Na_(2)O为0.41%~5.32%,Al_(2)O_(3)为17.81%~19.53%,K_(2)O为9.46%~11.91%,MgO为0.46%~1.36%,里特曼指数为7.54~17.01;稀土元素总量较高,高于300×10^(-6),强烈富集轻稀土元素,(La/Yb)N值大于10,个别达到100以上;亏损Nb、Ta、P等高场强元素,富集Rb、Th等大离子亲石元素,总体表现出富碱性岩石特征。锆石ε_(Hf)(t)值为-13.37~-9.30,对应的两阶段Hf模式年龄T_(DM2)为2102~1855 Ma。通过岩石成因分析和构造环境判别,赛马碱性杂岩可能形成于由俯冲挤压向陆内伸展、拉张转换的动力背景下的下地壳(或上地幔)部分熔融。赛马碱性杂岩侵位时代(225.8±1.9 Ma)可能代表了华北克拉通北缘岩石圈开始伸展减薄的时间,也是郯庐断裂形成的时间。 展开更多
关键词 LA-ICP-MS U-Pb年龄 HF同位素组成 晚三叠世 赛马碱性杂岩 辽东地区
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Ag(Ⅰ)Schiff碱配合物的合成及其对黄瓜花叶病毒的抑制作用 被引量:3
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作者 孟凡德 赵全芹 +1 位作者 李明霞 辛玉成 《应用化学》 CAS CSCD 北大核心 2002年第12期1183-1185,共3页
Five silver(Ⅰ) complexes with Schiff bases obtained from salicylaldehyde and five corresponding α-amino acids were synthesized. The complexes were characterized by elemental analysis, IR and 1H NMR measurements. Bio... Five silver(Ⅰ) complexes with Schiff bases obtained from salicylaldehyde and five corresponding α-amino acids were synthesized. The complexes were characterized by elemental analysis, IR and 1H NMR measurements. Bioactivity tests showed that the complexes inhibited the cucumber mosaic virus. Among them the best effective was glycine salicylaldehyde Schiffbase Ag(Ⅰ), which gave the effective level up to 74.7% towards CMV in dosage of 400 mg/L(in case of phaseolus vulgarisl inoculation). 展开更多
关键词 合成 SCHIFF碱 ag(I)配合物 黄瓜花叶病毒 银(I) 植物病毒
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溶液电火花法制备Ag-TiO_2纳米级复相超细粉及其光学性质 被引量:4
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作者 陈祖耀 刘宏杰 +2 位作者 刘方新 朱玉瑞 张国春 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 1999年第2期229-233,共5页
首次报道采用溶液电火花制备Ag—TiO2纳米级复相超细粉,XRD和TEM分析表明,所得产物可是金红石相也可是锐钛矿相,粒径分布均匀,一般在5~20nm内,超细粉经超声重新分散后所得纳米粒子的TEM像指出,许多粒子是由金属Ag粒子和TiO2粒子... 首次报道采用溶液电火花制备Ag—TiO2纳米级复相超细粉,XRD和TEM分析表明,所得产物可是金红石相也可是锐钛矿相,粒径分布均匀,一般在5~20nm内,超细粉经超声重新分散后所得纳米粒子的TEM像指出,许多粒子是由金属Ag粒子和TiO2粒子互相粘连构成葫芦状混合复相纳米结构,显示有比涂层修饰粒子略有减弱的增强激光拉曼散射(SERS)效应和相应的光学性质。讨论了含有Ag涂层的复合TiO2粒子与纯TiO2粒子互相粘连构成混合复相纳米粒子的可能性。 展开更多
关键词 二氧化钛 纳米级 复相超细粉 复合材料
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Ag/SiO_2复合纳米粒子的超声化学合成 被引量:2
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作者 朱文晶 张胜义 +2 位作者 庄永龙 金葆康 田玉鹏 《安徽大学学报(自然科学版)》 CAS 北大核心 2006年第5期65-68,94,共5页
本文中首先利用正硅酸乙酯(TEOS)的碱性水解制备了均匀分散的S iO2微球(粒径约70 nm),然后采用超声辐射与红外辐射结合的方法在其表面包覆了一层分布均匀的Ag纳米粒子(粒径约8 nm).研究了实验条件对产物的影响,并通过透射电镜(TEM)、X... 本文中首先利用正硅酸乙酯(TEOS)的碱性水解制备了均匀分散的S iO2微球(粒径约70 nm),然后采用超声辐射与红外辐射结合的方法在其表面包覆了一层分布均匀的Ag纳米粒子(粒径约8 nm).研究了实验条件对产物的影响,并通过透射电镜(TEM)、X射线衍射(XRD)、紫外可见吸收光谱(UV-vis)、差示扫描量热法(DSC)和红外吸收光谱(FT-IR)对产物的形貌及性质进行了表征. 展开更多
关键词 ag/SiO2复合纳米粒子 超声 合成 表征
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Ag(Ⅰ)Schiff碱配合物的合成及其晶体结构 被引量:4
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作者 张奇龙 张云黔 朱必学 《无机化学学报》 SCIE CAS CSCD 北大核心 2011年第11期2191-2194,共4页
本文以2-醛基吡啶和1,2-二(对氨基苯氧基)乙烷进行缩合得到Schiff碱配体L,再分别同AgNO3和AgClO4进行配位反应,得到了2个配合物[Ag2(NO3)2L](1)和{[AgL]ClO4}n(2),并用元素分析,FTIR和X-射线单晶衍射进行了表征。结果表明,配合物1属于... 本文以2-醛基吡啶和1,2-二(对氨基苯氧基)乙烷进行缩合得到Schiff碱配体L,再分别同AgNO3和AgClO4进行配位反应,得到了2个配合物[Ag2(NO3)2L](1)和{[AgL]ClO4}n(2),并用元素分析,FTIR和X-射线单晶衍射进行了表征。结果表明,配合物1属于单斜晶系,P21/c空间群,Ag(I)的配位环境为平面三角形,配体L同时和2个Ag(Ⅰ)离子配位形成双核配合物。配合物2属于单斜晶系,P21/n空间群,每个Ag(Ⅰ)的配位环境均为扭曲四面体,每个配体L通过其两端的2个氮原子同2个金属离子配位桥联形成一维螺旋链结构。 展开更多
关键词 席夫碱 ag(Ⅰ)配合物 晶体结构
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