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Fluid-induced high-temperature metasomatism at Rundv?gshetta in the Lützow-Holm Complex, East Antarctica: Implications for the role of brine during granulite formation 被引量:2
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作者 Kazuki Takahashi Toshiaki Tsunogae Emmanuel Nwachukwu Ugwuonah 《Geoscience Frontiers》 SCIE CAS CSCD 2018年第5期1309-1323,共15页
We report new petrological, phase equilibria modeling, and fluid inclusion data for pelitic and mafic granulites from Rundv?gshetta in the highest-grade region of the Neoproterozoic Lützow-Holm Complex(LHC),East ... We report new petrological, phase equilibria modeling, and fluid inclusion data for pelitic and mafic granulites from Rundv?gshetta in the highest-grade region of the Neoproterozoic Lützow-Holm Complex(LHC),East Antarctica, and provide unequivocal evidence for fluid-rock interaction and high-temperature metasomatism in the presence of brine fluid. The studied locality is composed dominantly of well-foliated pelitic granulite(K-feldspar+quartz+sillimanite+garnet+ilmenite) with foliation-parallel bands and/or layers of mafic granulite(plagioclase+orthopyroxene+garnet+ilmenite+quartz+biotite). The boundary between the two lithologies is defined by thin(about 1 -20 cm in thick) garnet-rich layers with a common mineral assemblage of garnet+plagioclase+quartz+ilmenite+biotite ? orthopyroxene. Systematic increase of grossular and decrease of pyrope contents in garnet as well as decreasing Mg/(Fe+Mg) ratio of biotite from the pelitic granulite to garnet-rich rock and mafic granulite suggest that the garnet-rich layer was formed by metasomatic interaction between the two granulite lithologies. Phase equilibria modeling in the system NCKFMASHTO demonstrates that the metasomatism took place at 850 -860℃, which is slightly lower than the peak metamorphism of this region, and the modal abundance of garnet is the highest along the metapeliteemetabasite boundary(up to 40%), which is consistent with the field and thin section observations. The occurrence of brine(7.0 -10.9 wt.% Na Cleqfor ice melting or 25.1 -25.5 wt.% NaC leqfor hydrohalite melting) fluid inclusions as a primary phase trapped within plagioclase in the garnet-rich layer and the occurrence of Cl-rich biotite(Cl = 0.22 -0.60 wt.%) in the metasomatic rock compared to that in pelitic(0.15 -0.24 wt.%) and mafic(0.06-0.13 wt.%) granulites suggest infiltration of brine fluid could have given rise to the high-temperature metasomatism. The fluid might have been derived from external sources possibly related to the formation of major suture zones formed during the Gondwana amalgamation. 展开更多
关键词 High-temperature METASOMATISM BRINE Phase equilibrium modeling Fluid INClUSION GONDWANA lützow-holm complex
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Detrital zircon geochronology of the Lutzow-Holm Complex,East Antarctica:Implications for Antarctica-Sri Lanka correlation 被引量:6
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作者 Yusuke Takamura Toshiaki Tsunogae +1 位作者 M.Santosh Yukiyasu Tsutsumi 《Geoscience Frontiers》 SCIE CAS CSCD 2018年第2期355-375,共21页
The Lützow-Holm Complex(LHC) of East Antarctica has been regarded as a collage of Neoarchean(ca.2.5 Ga), Paleoproterozoic(ca. 1.8 Ga), and Neoproterozoic(ca. 1.0 Ga) magmatic arcs which were amalgamated through t... The Lützow-Holm Complex(LHC) of East Antarctica has been regarded as a collage of Neoarchean(ca.2.5 Ga), Paleoproterozoic(ca. 1.8 Ga), and Neoproterozoic(ca. 1.0 Ga) magmatic arcs which were amalgamated through the latest Neoproterozoic collisional events during the assembly of Gondwana supercontinent. Here, we report new geochronological data on detrital zircons in metasediments associated with the magmatic rocks from the LHC, and compare the age spectra with those in the adjacent terranes for evaluating the tectonic correlation of East Antarctica and Sri Lanka. Cores of detrital zircon grains with high Th/U ratio in eight metasediment samples can be subdivided into two dominant groups:(1) late Meso-to Neoproterozoic(1.1-0.63 Ga) zircons from the northeastern part of the LHC in Prince Olav Coast and northern Soya Coast areas, and(2) dominantly Neoarchean to Paleoproterozoic(2.8-2.4 Ga) zircons from the southwestern part of the LHC in southern Lutzow-Holm Bay area. The ca.1.0 Ga and ca. 2.5 Ga magmatic suites in the LHC could be proximal provenances of the detrital zircons in the northeastern and southwestern LHC, respectively. Subordinate middle to late Mesoproterozoic(1.3-1.2 Ga) detrital zircons obtained from Akarui Point and Langhovde could have been derived from adjacent Gondwana fragments(e.g., Rayner Complex, Eastern Ghats Belt). Meso-to Neoproterozoic domains such as Vijayan and Wanni Complexes of Sri Lanka, the southern Madurai Block of southern India, and the central-western Madagascar could be alternative distal sources of the late Meso-to Neoproterozoic zircons. Paleo-to Mesoarchean domains in India, Africa, and Antarctica might also be distal sources for the minor ~2.8 Ga detrital zircons from Skallevikshalsen. The detrital zircons from the Highland Complex of Sri Lanka show similar Neoarchean to Paleoproterozoic(ca. 2.5 Ga) and Neoproterozoic(ca. 1.0 Ga) ages, which are comparable with those of the LHC, suggesting that the two complexes might have formed under similar tectonic regimes. We consider that the Highland Complex and metasedimentary unit of the LHC formed a unified latest Neoproterozoic suture zone with a large block of northern LH-Vijayan Complex caught up as remnant of the ca. 1.0 Ga magmatic arc. 展开更多
关键词 The northern lützow-holm-Vijayan complex Zircon U-Pb geochronology Crustal evolution Tectonic correlations Gondwana supercontinent
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The Impact of Storyline Complexity on L2 Learners’Written Performance
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作者 CHEN Yu-lian 《Journal of Literature and Art Studies》 2024年第5期369-372,共4页
Task-based Language Teaching(TBLT)research has provided ample evidence that cognitive complexity is an important aspect of task design that influences learner’s performance in terms of fluency,accuracy,and syntactic ... Task-based Language Teaching(TBLT)research has provided ample evidence that cognitive complexity is an important aspect of task design that influences learner’s performance in terms of fluency,accuracy,and syntactic complexity.Despite the substantial number of empirical investigations into task complexity in journal articles,storyline complexity,one of the features of it,is scarcely investigated.Previous research mainly focused on the impact of storyline complexity on learners’oral performance,but the impact on learners’written performance is less investigated.Thus,this study aims at investigating the effects of narrative complexity of storyline on senior high school students’written performance,as displayed by its complexity,fluency,and accuracy.The present study has important pedagogical implications.That is,task design and assessment should make a distinction between different types of narrative tasks.For example,the task with single or dual storyline.Results on task complexity may contribute to informing the pedagogical choices made by teachers when prioritizing work with a specific linguistic dimension. 展开更多
关键词 storyline complexity narrative writing task complexity l2 writers
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λ-Red重组技术结合复合诱变提高大肠杆菌L-异亮氨酸合成能力
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作者 汪吉鹏 朱滕滕 +4 位作者 刘璐 马铖 魏晓博 刘慧燕 方海田 《食品工业科技》 北大核心 2025年第2期167-174,共8页
本研究旨在通过λ-Red重组技术结合复合诱变方法提高大肠杆菌L-异亮氨酸合成能力。以E. coli NXA为出发菌株,首先采用λ-Red同源重组敲除编码支链氨基酸转运蛋白基因brnQ,获得突变菌株E. coli NXA1。然后将E. coli NXA1经常温常压等离子... 本研究旨在通过λ-Red重组技术结合复合诱变方法提高大肠杆菌L-异亮氨酸合成能力。以E. coli NXA为出发菌株,首先采用λ-Red同源重组敲除编码支链氨基酸转运蛋白基因brnQ,获得突变菌株E. coli NXA1。然后将E. coli NXA1经常温常压等离子体(ARTP)、紫外(UV)与亚硝基胍(NTG)多轮复合诱变,以α-氨基丁酸(α-AB)为结构类似物进行筛选,筛选得到突变菌株E. coli NXA2。摇瓶发酵结果表明,在37℃、200 r/min条件下发酵40 h后,E. coli NXA1的L-异亮氨酸滴度为2.76 g/L,较E. coli NXA提高了33.98%;E. coli NXA2的L-异亮氨酸滴度为3.22 g/L,较E. coli NXA1提高了16.67%,较E. coli NXA提高了56.31%。对菌株E. coli NXA2经连续传代20代后,表现出较好的遗传稳定性。λ-Red重组技术结合复合诱变对大肠杆菌提高L-异亮氨酸合成能力有明显效果,为选育L-异亮氨酸高产菌株奠定理论基础。 展开更多
关键词 大肠杆菌 λ-Red重组技术 brnQ基因 复合诱变 发酵 l-异亮氨酸
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A Comparative Analysis of Syntactic Complexity in Applied Linguistics Abstracts Written by Chinese Novice Writers and Native English Advanced Writers
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作者 Mingming Zhao Tianshuang Ge 《Open Journal of Applied Sciences》 2024年第1期1-26,共26页
The rhetorical structure of abstracts has been a widely discussed topic, as it can greatly enhance the abstract writing skills of second-language writers. This study aims to provide guidance on the syntactic features ... The rhetorical structure of abstracts has been a widely discussed topic, as it can greatly enhance the abstract writing skills of second-language writers. This study aims to provide guidance on the syntactic features that L2 learners can employ, as well as suggest which features they should focus on in English academic writing. To achieve this, all samples were analyzed for rhetorical moves using Hyland’s five-rhetorical move model. Additionally, all sentences were evaluated for syntactic complexity, considering measures such as global, clausal and phrasal complexity. The findings reveal that expert writers exhibit a more balanced use of syntactic complexity across moves, effectively fulfilling the rhetorical objectives of abstracts. On the other hand, MA students tend to rely excessively on embedded structures and dependent clauses in an attempt to increase complexity. The implications of these findings for academic writing research, pedagogy, and assessment are thoroughly discussed. 展开更多
关键词 Syntactic complexity Rhetorical Functions Research Article Abstract l2 Academic Writing
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Synthesis,characterization,photoluminescence and electroluminescence properties of new 1,3,4-oxadiazole-containing rhenium(I)complex Re(CO)_3(Bphen)(PTOP) 被引量:2
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作者 Yan Ping Wang Wen Fa Xie +1 位作者 Bin Li Wen Lian Li 《Chinese Chemical Letters》 SCIE CAS CSCD 2007年第12期1501-1504,共4页
A new 1,3,4-oxadiazole-contanining rhenium(I) complex, with the formula [Re(CO)a(Bphen)(PTOP)], (Bphen = bathophe- nardine, PTOP = 4-(5-p-tolyl-1,3, 4-oxadiazd-2-yl) pyridine), is synthesized and character... A new 1,3,4-oxadiazole-contanining rhenium(I) complex, with the formula [Re(CO)a(Bphen)(PTOP)], (Bphen = bathophe- nardine, PTOP = 4-(5-p-tolyl-1,3, 4-oxadiazd-2-yl) pyridine), is synthesized and characterized by elemental analysis, IR, 1H NMR, UV-vis and luminescence spectroscopy. The double-layer electroluminescence devices based on the Re(l) complex have been fabricated by spin-coating technique. The turn-on voltage, maximum efficiency, and brightness for green emission obtained from the devices are 9 V, 2.1 cd/A and 165 cd/m^2, respectively. 展开更多
关键词 Rhenium(l complex Oxadizole-founctionalized ElECTROlUMINESCENCE
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Highly Luminescent Host-Guest Systems Based on Zeolite L and Lanthanide Complexes 被引量:1
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作者 王弋戈 郭枝 李焕荣 《Journal of Rare Earths》 SCIE EI CAS CSCD 2007年第S1期283-285,共3页
Supramolecular incorporation of lanthanide complex has been obtained by loading of organic ligand into Eu3+-exchanged zeolite L. This was achieved by a two-step procedure: (1) zeolite L was ion-exchanged with Eu(Ⅲ) i... Supramolecular incorporation of lanthanide complex has been obtained by loading of organic ligand into Eu3+-exchanged zeolite L. This was achieved by a two-step procedure: (1) zeolite L was ion-exchanged with Eu(Ⅲ) ions; (2) organic ligand was then loaded into the channels of the Eu3+-exchanged zeolite by gas diffusion procedure. Loading of ligand into the channels of zeolite L was confirmed by element analysis. Luminescence spectroscopy has confirmed that lanthanide complex are formed in the nanochannels of zeolite L crystals. In addition to the sharp emissions of lanthanide ions, broad band ranged from 350~500 nm can also be observed. This study provides alternative method for fabricating full-color display materials. 展开更多
关键词 lanthanide complex zeolite l HOST-GUEST lUMINESCENCE SENSITIZATION rare earths
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Image separation using wavelet-complex shearlet dictionary 被引量:2
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作者 Shuaiqi Liu Shaohai Hu Yang Xiao 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2014年第2期314-321,共8页
This paper presents a new method for image separation through employing a combined dictionary consisting of wavelets and complex shearlets. Because the combined dictionary sparsely represents points and curvilinear si... This paper presents a new method for image separation through employing a combined dictionary consisting of wavelets and complex shearlets. Because the combined dictionary sparsely represents points and curvilinear singularities respectively, the image can be decomposed into pointlike and curvelike parts as accurate as possible. The proposed method based on the geo- metric separation theory introduced by Donoho in 2005 shows that accurate geometric separation of the morphologically distinct fea- tures of points and curves can be achieved by l1 minimization. The experimental results show that the proposed method can not only be effective but also greatly reduce the computing time. 展开更多
关键词 geometric separation l1 minimization sparse approx-imation complex shearlet.
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Infrasound Signals and Their Source Location Inferred from Array Deployment in the Lützow-Holm Bay Region, East Antarctica: January-June 2015 被引量:2
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作者 Takahiko Murayama Masaki Kanao +1 位作者 Masa-Yuki Yamamoto Yoshiaki Ishihara 《International Journal of Geosciences》 2017年第2期181-188,共8页
Characteristic features of infrasound waves observed in the Antarctic represent a physical interaction relating surface environment in the continental margin and surrounding Southern Ocean. Source location of several ... Characteristic features of infrasound waves observed in the Antarctic represent a physical interaction relating surface environment in the continental margin and surrounding Southern Ocean. Source location of several infrasound events is demonstrated by using combination of two array deployments along a coast of the Lützow-Holm Bay (LHB), East Antarctica, for data retrieving period in January-June 2015. These infrasound arrays being established in January 2013 clearly detected temporal variations in frequency content and propagation direction of the identified seven large events. Many of these sources are assumed to have cryoseismic origins;the ice-quakes associated with calving of glaciers, discharge of sea-ice, collision between sea-ice and icebergs around the LHB. Detail and continuous measurements of infrasound waves in the Antarctic are a proxy for monitoring regional environment as well as climate change in high southern latitude. 展开更多
关键词 INFRASOUND ARRAY Observations lützow-holm BAY East ANTARCTICA Microbaroms Ice SHOCKS Surface Environment
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Synthesis,Characterization and Antibacterial Properties of Rare Earth (Ce^(3+) ,Pr^(3+) ,Nd^(3+) ,Sm^(3+) ,Er^(3+) ) Complexes with L-Aspartic Acid and o-Phenanthroline 被引量:16
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作者 郁慧 何其庄 +1 位作者 杨静 郑文捷 《Journal of Rare Earths》 SCIE EI CAS CSCD 2006年第z2期4-8,共5页
Five novel ternary complexes of rare earth ions with L-Aspartic acid (Asp) and o-phenanthroline (Phen) were synthesized in ethanol aqueous solution. Their compositions were characterized by elemental analysis, molar c... Five novel ternary complexes of rare earth ions with L-Aspartic acid (Asp) and o-phenanthroline (Phen) were synthesized in ethanol aqueous solution. Their compositions were characterized by elemental analysis, molar conductance, FT-IR, Raman, UV-VIS and TG-DTA. The compositions of the complexes were confirmed to be: RE( Asp)3PhenCl3·3H2O (RE: Ce3+ , Pr3+ , Nd3+ , Sm3+ , Er3+ ). The antibacterial activity test shows that all these complexes exhibit excellent antibacterial ability against Escherichia coli, Staphylococcus aureus and Candida albicans. The antimicrobial spectrum of the complexes are broad. 展开更多
关键词 complexES O-PHENANTHROlINE l-Aspartic acid antibacterial activity rare earths
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Seismic Tremors and Their Relation to Cryosphere Dynamics in April 2015 around the Lützow-Holm Bay, East Antarctica 被引量:1
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作者 Masaki Kanao Takahiko Murayama +1 位作者 Masa-Yuki Yamamoto Yoshiaki Ishihara 《International Journal of Geosciences》 2017年第8期1025-1047,共23页
Characteristics and statistics of seismic tremors occurring during April 2015 were investigated by using short-period and broadband seismographs deployed at Syowa Station (SYO), in the Lützow-Holm Bay (LHB), East... Characteristics and statistics of seismic tremors occurring during April 2015 were investigated by using short-period and broadband seismographs deployed at Syowa Station (SYO), in the Lützow-Holm Bay (LHB), East Antarctica. In order to examine a relationship between surface environments in particular cryosphere variation, the MODIS satellite images were utilized for comparison with the detected tremor events. Since a large volume of sea-ice was discharged during the April, together with several large icebergs passed through from the west to the east at northern edge of the fast sea-ice of LHB, it was expected to detect seismic tremors involving cryospehre dynamics. During the month, a total number of 49 tremor events including short duration ice shocks were identified. Majority of the events (N = 39) had their duration times more than 15 minutes, which were divided into both tremors and ice shocks on the basis of experienced definition at SYO. Cryospheric sources recorded by seismic tremors were classified into several origins (collision, calving, crevassing, crashing, etc.): “crevassing events” along the large cracks inside the fast sea-ice in LHB (04 April), “discharge events” of fast sea-ice from the Bay (07 April), “collision events” between iceberg and the edge of fast sea-ice (14 April), “crashing movement” between fragmentation of fast sea-ice and packed sea-ice (18 April), and other origins. In particular, strong amplitude tremors with harmonic overtones were assumed to be occurred independently from whether condition, because these overtone tremors were identified at less stormy days by comparison with infrasound data at SYO. 展开更多
关键词 SEISMIC Tremors Ice Shocks CRYOSPHERE DYNAMICS SEA-ICE ICEBERGS lützow-holm BAY Antarctica
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Genre Effect on L2 Syntactic Complexity and Holistic Rating for Writing Quality of Intermediate EFL Learners 被引量:1
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作者 Lili ZHANG Haitao LIU 《Chinese Journal of Applied Linguistics》 2021年第4期451-469,589,共20页
This exploratory study examines whether genre has an impact on syntactic complexity and holistic rating in EFL writing. Over 300 sample texts produced by intermediate learners were collected from a test and some regul... This exploratory study examines whether genre has an impact on syntactic complexity and holistic rating in EFL writing. Over 300 sample texts produced by intermediate learners were collected from a test and some regular after-class assignments for English writing courses. Each participant completed two writing tasks, one argumentative and the other narrative. Results show that genre type has a significant impact on L2 syntactic complexity. Genre effect is found stronger with timed writing tasks. L2 holistic ratings show correlation with syntactic complexity on the different measure(s) depending on genre type and planning conditions. Regression analyses reveal that for timed writing tasks, clausal density(clauses per sentence) is a reliable predictor for holistic assessment on intermediate EFL learners’ writing quality. It is found to account for 6% of the score variance for timed writing and 10% for timed argumentative writing. Genre is evidenced to be related to EFL writing holistic ratings. Closer examination indicates that while syntactic complexity is predictive of holistic writing scores for argumentative writing, it does not correlate with holistic scores for narrative writing. Other linguistic features rather than syntactic complexity may be accountable. Overall, the study lends support to genre effect in the relationship between syntactic complexity and L2 writing quality holistic rating. 展开更多
关键词 genre effect syntactic complexity l2 writing holistic rating intermediate learner
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Co Complexes as a Corrosion Inhibitor for 316 L Stainless Steel in H2SO4 Solution 被引量:1
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作者 Amin Rabiei Baboukani Ehsan Sharifi +1 位作者 Saeid Akhavan Ahmad Saatchi 《Journal of Materials Science and Chemical Engineering》 2016年第9期28-35,共9页
The effect of Co complexes with a Schiff base ligand on the electrochemical corrosion behavior of 316 L SS in 0.1 M H<sub>2</sub>SO<sub>4</sub> at 25℃ has been investigated at various inhibito... The effect of Co complexes with a Schiff base ligand on the electrochemical corrosion behavior of 316 L SS in 0.1 M H<sub>2</sub>SO<sub>4</sub> at 25℃ has been investigated at various inhibitor concentration using electrochemical techniques (impedance spectroscopy (EIS), polarization curves). Corrosion measurements indicate that Co complex act as moderately inhibitors. Results revealed that increasing the concentration of Co complex increases the corresponding IE% values till 100 ppm. Co complex acts as mixed type inhibitors with predominant effect on the anodic dissolution of iron. Adsorption studies showed that the process follows Langmuir adsorption isotherm. 展开更多
关键词 Corrosion Inhibitors Co complex 316 l Stainless Steel POlARIZATION EIS
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A Thermochemical Study on Complex Nickel(Ⅱ) L-α-Histidine 被引量:2
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作者 GAO Sheng li CHEN San ping +1 位作者 HU Rong zu SHI Qi zhen 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2003年第2期227-230,共4页
The formation enthalpy of complex nickel(Ⅱ) histidine(His) in water was determined by means of microcalorimetry in the temperature range of 298 15-323 15 K. The standard enthalpy of the formation of Ni(His) 2... The formation enthalpy of complex nickel(Ⅱ) histidine(His) in water was determined by means of microcalorimetry in the temperature range of 298 15-323 15 K. The standard enthalpy of the formation of Ni(His) 2+ 2(aq) was calculated. On the basis of the experimental and the calculated results, three thermodynamic parameters(the activation enthalpy, the activation entropy and the activation free energy), the rate constants, three kinetic parameters(the apparent activation energy, the pre exponential constant and the reaction order) of the formation reaction of the title complex were obtained. 展开更多
关键词 Nickel chloride l-α-Histidine complex Formation reaction THERMOKINETICS
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ON THE LINEAR COMPLEXITY OF FCSR SEQUENCES 被引量:2
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作者 Qi Wenfeng Xu HongDept of Appl.Math,Zhengzhou Information Engineering Univ., Zhengzhou 450002,China 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2003年第3期318-324,共7页
The linear complexity of a new kind of keystream sequences.FCSR sequences,is discussed by use of the properties of cyclotomic polynomials.Based on the results of C.Seo's,an upper bound and a lower bound on the li... The linear complexity of a new kind of keystream sequences.FCSR sequences,is discussed by use of the properties of cyclotomic polynomials.Based on the results of C.Seo's,an upper bound and a lower bound on the linear complexity of a significant kind of FCSR sequences—l-sequences are presented. 展开更多
关键词 linear recurring sequence feedback with carry shift register l-sequences linear complexity
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Synthesis,Characterization,and DNA Binding Properties of Dinuclear Copper(Ⅱ) Complex [Cu_2(TATP)_2(L-Leu)_2(ClO_4)_2]_2·2H_2O 被引量:1
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作者 GU Qin LIN Qing-bin +2 位作者 LIU Ying-ju LE Xue-yi FENG Xiao-long 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2008年第4期401-406,共6页
A dinuclear copper(Ⅱ) complex[Cu2(TATP)2(L-Leu)2(CIO4)2]2·2H2Owas synthesized and characterized, where, TATP=1,4,8,9-tetraazatriphenylene, and L-Leu=L-leucinate. The complex was crystallized in the tricl... A dinuclear copper(Ⅱ) complex[Cu2(TATP)2(L-Leu)2(CIO4)2]2·2H2Owas synthesized and characterized, where, TATP=1,4,8,9-tetraazatriphenylene, and L-Leu=L-leucinate. The complex was crystallized in the triclinic space group P1, with two independent molecules in a unit cell. Two Cu(Ⅱ) ions in each complex [Cu2(TATP)2(L-Leu)2(CIO4)2] molecule were found to be in different coordination geometries, i.e., Cu2 or Cu4 of a distorted square-pyramidal geometry coordinated with two nitrogens of TATP, the amino nitrogen and one carboxylate oxygen of L-Leu and one oxygen of perchlorate, and Cul or Cu3 with an octahedral geometry coordinated with the above stated similar coordinated atoms, and another carboxylate oxygen of L-Leu coordinating to Cu2 or Cu4. The complex can interact with CT-DNA by an intercalative mode and cleave pBR322 DNA in the presence of ascorbate. 展开更多
关键词 Copper(Ⅱ) complex 1 4 8 9-Tetraazatriphenylene l-leucinate DNA
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Synthesis, Characterization and Antibacterial Properties of Rare Earth Complexes with L-Phenylalanine and o-Phenanthroline 被引量:1
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作者 Yang Jing He Qizhuang Yu Hui Feng Jie Sun Jianjian 《Journal of Rare Earths》 SCIE EI CAS CSCD 2006年第1期124-124,共1页
New solid ternary complexes of rare earth with L-Phenylalanine ( L-Phe ) and o-Phenanthroline (Phen) were synthesized in ethyl alcohol solution. Their composition were characterized by elemental analysis, molar co... New solid ternary complexes of rare earth with L-Phenylalanine ( L-Phe ) and o-Phenanthroline (Phen) were synthesized in ethyl alcohol solution. Their composition were characterized by elemental analysis, molar conductance, IR, Raman, UV-VIS, TG-DTA. The compositions of the complexes were confirmed to be RE ( Phe )3Phen Cl3 · 3H2O ( RE = La^3+, Ce^3+, Pr^3+, Nd^3+, Sm^3+, Eu^3+, Er^3+, Y^3+). The antibacterial activities testing indicates that all these solid ternary complexes have antibacterial ability against Escherich coli, Staphy lococcus aureus, Candida albican (MIC are about 65 × 10^-4%, 15 × 10^-3%, 4 × 10^-2%, respectively). 展开更多
关键词 l-PHENYlAlANINE O-PHENANTHROlINE ternary complex rare earths
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Synthesis, Structure and Thermal Behaviors of a Magnesium(Ⅱ) Complex with Tetrazole-1-acetic Acid 被引量:2
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作者 李志敏 张同来 +3 位作者 张国涛 杨利 周遵宁 张建国 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2013年第7期981-988,共8页
A new complex of magnesium with tetrazole-l-acetic acid (tza) has been synthe- sized and characterized by elemental analysis and FT-IR spectrum. Single-crystal X-ray diffraction analysis determined the molecular for... A new complex of magnesium with tetrazole-l-acetic acid (tza) has been synthe- sized and characterized by elemental analysis and FT-IR spectrum. Single-crystal X-ray diffraction analysis determined the molecular formula as Mg(tza)2(H20)4. The crystal belongs to the triclinic system with Pi space group, and a = 6.133(2), b = 6.488(2), c = 10.0127(7) A, a = 77.282(10), fl = 91.558(1), ), = 76.002(8)°, Y = 349.0(2)A3, Z = 1, C6HI4MgNsOs, Mr = 350.56, Dc = 1.668 g.cm-3, F(000) = 182,μ = 0.189, S = 1.000, the final R = 0.0294 and wR = 0.0785 for 1128 observed reflections with I 〉 20-(I). In this molecule, the tza ion exhibits an infrequent monodentate coordination mode. The magnesium center is hexa-coordinated to a slightly distorted octahedral configuration by six oxygen atoms from two tza ligands and four coordinated water molecules. DSC and TG-DTG analyses were applied to assess the thermal decomposition behavior. The kinetic parameters of the exothermal peak were calculated by non-isothermal reaction kinetics. The values of critical temperature of thermal explosion, △S≠, △H≠ and △G^≠, were obtained as 596 K, -42.25 J mo1^-1 K^-1, 296.43 kJ mol^-1 and 323.53 kJ mol1, respectively. 展开更多
关键词 energetic materials magnesium complex tetrazole-l-acetic acid crystal structure thermal behavior
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A Copper(Ⅱ)Complex Based on N-(4-hydroxybenzyl)-L-serine:Synthesis,Crystal Structure and Inhibitory Activity on PTP1B and TCPTP 被引量:2
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作者 李艳红 卢丽萍 +3 位作者 朱苗力 袁彩霞 冯思思 高增强 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2016年第11期1686-1693,共8页
A novel copper(II) complex with the reduced Schiff base, [Cu(L)2]·H2O (I, HL = N-(4-hydroxybenzyl)-L-serine), was prepared in aqueous solution and characterized by elemental analysis, FT-IR, electrospray ... A novel copper(II) complex with the reduced Schiff base, [Cu(L)2]·H2O (I, HL = N-(4-hydroxybenzyl)-L-serine), was prepared in aqueous solution and characterized by elemental analysis, FT-IR, electrospray ionization mass spectrometry and single-crystal X-ray diffraction. Complex I crystallizes in the orthorhombic system, space group P212121, with a = 8.9040(18), b = 9.1530(18), c = 24.891(5)A^°, V = 2028.6(7) A^°3, Z = 4, C20H26CuN2O9, Mr = 501.97, Dc = 1.644g·cm^3, μ = 1.135 mm^-1, F(000) = 1044, GOOF = 1.194, the final R = 0.0484 and wR = 0.1420 for 6186 observed reflections (I 〉 2σ(I)). In I, two L^- anions are coordinated to the copper ion in tridentate and bidentate chelating modes, respectively, resulting in the coordinated geometry of copper ion to be a distorted square pyramid. The intermolecular hydrogen bonds between the complexes, complexes and lattice water molecules lead to a 2D supramolecular network. The bioactivity of the complex as a potential PTPs inhibitory agent in vitro was investigated, displaying potent inhibition against PTP1B (IC50, 0.27 μM) and TCPTP (IC50, 0.57 μM) with a moderate selectivity. 展开更多
关键词 copper(Ⅱ) complex N-(4-hydroxybenzyl)-l-serine crystal structure inhibitor PTP1B TCPTP
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Syntheses, Crystal Structures and Fluorescence Properties of Two Pb(Ⅱ) 1-Naphthoate Complexes 被引量:1
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作者 侯照君 王修光 +1 位作者 戴沛霞 杨恩翠 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2012年第9期1295-1300,共6页
Two new 1-naphthoate-based Pb(Ⅱ) complexes, [Pb(phen)(NA)2]n 1 and [Pb(bpp)(NA)2]n 2 (NA = 1-naphthoate, phen = 1,10-phenanthroline, and bpp = 1,3-bi(4-pyri- dyl)propane), were hydrothermally synthesize... Two new 1-naphthoate-based Pb(Ⅱ) complexes, [Pb(phen)(NA)2]n 1 and [Pb(bpp)(NA)2]n 2 (NA = 1-naphthoate, phen = 1,10-phenanthroline, and bpp = 1,3-bi(4-pyri- dyl)propane), were hydrothermally synthesized and structurally characterized. 1 is of monoclinic system, space group C2/c with a = 28.114(3), b = 10.9601(10), c = 8.6843(8) , β = 93.3760(10)°, V = 2671.3(4) 3, Dc = 1.814 g/cm3, Mr = 729.73, Z = 4, F(000) = 1416, μ = 6.360 mm-1, the final R = 0.0346 and wR = 0.0948 for 2184 observed reflections with I 〉 2σ(I). Complex 2 crystallizes in monoclinic, space group C2/c with a = 26.491(2), b = 8.7773(6), c = 27.893(2) , β = 113.3020(10)°, V = 5956.8(8)3, Dc = 1.668 g/cm3, Mr = 747.78, Z = 8, F(000) = 2928, μ = 5.706 mm-1, the final R = 0.0211 and wR = 0.0493 for 3677 observed reflections with I 〉 2σ(I). Both complexes present one-dimensional (1-D) zigzag chains extended by anionic NA linkers for 1 and bridged by neutral bpp connectors for 2, which are further aggregated into 2-D supramolecular networks by interchain π···π stacking interactions. In addition, the two solid-state complexes exhibit different strong emissions at room temperature, suggesting their potential applications as fluorescence materials. 展开更多
关键词 l-naphthoic acid Pb(II) complexes crystal structures fluorescence property
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