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Elastic and Seismic Properties of Dabie-Sulu Ultrahigh Pressure Metamorphic Rocks

Acta Geologica Sinica(English Edition) 2012年第1期86卷 20-37页

作者： WANG Qian JI Shaocheng SUN Shengsi matthew H.SALISBURY Hartmut KERN State Key Laboratory of Isotope Geochemistry Guangzhou Institute of GeochemistryChinese Academy of SciencesGuangzhou 510640China Departement des Genies Civil Geologique et des MinesEcole Polytechnique de Montreal Montreal H3C 3A7Canada State Key Laboratory of Continental tectonics and Dynamics Institute of GeologyChinese Academy of Geological SciencesBeijing 100037China Geological Survey of Canada-Atlantic Bedford Institute of OceanographyDartmouth B2Y 4A2Canada Institutfur Geowissenschaften Universitat Kiel24098 KielGermany

Lame modulus （λ） and shear modulus （μ） are among the most important, intrinsic, elastic constants of rocks. Using 7. and μ could be much more advantageous than using P- and S-wave velocities （Vp and Vs）. Here we quantified these equivalent isotropic elastic moduli for 115 representative rocks from the ultrahigh pressure （UHP） metamorphic terrane of the Dabie-Sulu orogenic belt （China） and their variations with pressure （P）, temperature （t）, density （p）, Vp, Vs and mineralogical composition. Both moduli increase nonlinearly and linearly with increasing pressure at low （〈200-300 MPa） and high （〉200-300 MPa） pressures, respectively. In the regime of high pressures, 7. and IX decrease quasi-linearly with increasing temperature with temperature derivatives dλ/dt and dμ/dt generally in the range of -10×10-3 to -1×10-3 GPa/℃. Dehydration of water-bearing minerals such as serpentine in peridotites and chlorite in retrograde eciogites results in an abrupt drop in 7. while μ remains almost unchanged. In Z-p, μ-p and 7.-IX plots, the main categories of UHP rocks can be characterized. Serpentinization leads to significant decreases in μ and 7. as serpentine has extremely low values of Z, μ and p. Eclogites, common mafic rocks （mafic gneiss, metagabbro and amphibolite）, and felsic rocks （orthogneiss and paragneiss） have high, moderate and low μ and λ values, respectively. For pyroxenes and olivines, λ increases but μ decreases with increasing Fe/Mg ratios. For plagioclase feldspars, both Z and μ exhibit a significant positive correlation with anorthite content. SiO2-rich felsic rocks and quartzites are deviated remarkably from the general trend lines of the acid-intermediate-mafic rocks in Vs-p, μ-p, λ-Vp,λ-Vs and μ-λ diagrams because quartz has extremely low λ （-8.1 GPa） and p （2.65 g/cm3） but moderate μ （44.4 GPa） values. Increasing the contents of garnet, rutile, ilmenite and magnetite results in a significant increase in the λ and μ values of the UHP metamorphic rocks. Howev

关键词： seismic properties elastic constants ultrahigh pressure metamorphic rocks Dabie-Sulu,deep continental roots

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A Single Active trehalose-6-P Synthase （tPS） and a Family of Putative Regulatory tPS-Like Proteins in Arabidopsis

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Molecular Plant 2010年第2期3卷 406-419页

作者： Lies Vandesteene matthew Ramon Katrien Le Roy Patrick Van Dijck Filip Rolland Laboratory of Functional Biology Plant Metabolic Signaling Group Institute of Botany and Microbiology KU Leuven Kasteelpark Arenberg 31-bus 2438 B-3001 Heverlee Belgium Department of Molecular Biology Harvard Medical School Massachusetts General Hospital Boston USA Laboratory of Molecular Plant Physiology Institute of Botany and Microbiology KU Leuven Belgium Department of Molecular Microbiology VIB Leuven Belgium Laboratory of Molecular Cell Biology Institute of Botany and Microbiology KU Leuven Belgium

Higher plants typically do not produce trehalose in large amounts, but their genome sequences reveal large families of putative trehalose metabolism enzymes. An important regulatory role in plant growth and development is also emerging for the metabolic intermediate trehalose-6-P （t6P）. Here, we present an update on Arabidopsis trehalose me- tabolism and a resource for further detailed analyses. In addition, we provide evidence that Arabidop$is encodes a single trehalose-6-P synthase （tPS） next to a family of catalytically inactive tPS-like proteins that might fulfill specific regulatory functions in actively growing tissues.

关键词： trehalose metabolism tPS Arabidopsis.

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MICROStRUCtURES AND MECHANICAL PROPERtIES OF IN-SItU Al_2O_3/tiAl COMPOSItES BY EXOtHERMIC DISPERSION MEtHOD

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Acta Metallurgica Sinica(English Letters) 2008年第6期21卷 437-443页

作者： t.t. Ai Department of Materials Science and Engineering Shaanxi University of Technology Hanzhong 723003 China

In-situ Al2O3/tiAl composites were fabricated by pressure-assisted exothermic dispersion （PAXD） method from elemental powder mixtures of ti, Al, tiO2, and Nb2O5. the microstructures and mechanical properties of the as-sintered composites are investigated. the results show that the as-sintered products consist of γ-tiAl, α2-ti3Al, Al2O3, and NbAl3 phases. Microstructure analysis indicates that Al2O3 particles tend to disperse on the grain boundaries. Application of a moderate pressure of 35 MPa at 1200℃ yields Al2O3/tiAl composites with fine Al2O3 reinforcement and a discontinuous network linking by Al2O3 particles. the aluminide component has a fine submicron γ ＋α2 lamellar microstructure. With increasing Nb2O5 content, Al2O3 particles are dispersed uniformly in the matrix. the hardness of the composites increases gradually, and the bending strength and fracture toughness of the composites reach to the maximum value, respectively.

关键词： Al2 O3/tiAl composites Microstructure Mechanical properties

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A biodegradable microgrooved and tissue mechanocompatible citrate-based scaffold improves bladder tissue regeneration

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Bioactive Materials 2024年第11期41卷 553-563页

作者： Madeleine Goedegebuure matthew I.Bury Xinlong Wang Pasquale Sanfelice Federico Cammarata Larry Wang tiffany t.Sharma Nachiket Rajinikanth Vikram Karra Vidhika Siddha Arun K.Sharma Guillermo A.Ameer Department of Biomedical Engineering Northwestern UniversityEvanstonILUSA Department of Surgery Division of UrologyLurie Children's Hospital of ChicagoChicagoILUSA Department of Urology Feinberg School of MedicineNorthwestern UniversityChicagoILUSA Department of Surgery Feinberg School of MedicineNorthwestern UniversityChicagoILUSA Center for Advanced Regenerative Engineering Northwestern UniversityChicagoILUSA International Institute for Nanotechnology Northwestern UniversityChicagoILUSA Simpson Querrey Institute Northwestern UniversityChicagoILUSA Chemistry for Life Processes Institute Northwestern UniversityChicagoILUSA Stanley Manne Children's Research Institute Lurie Children's Hospital of ChicagoChicagoILUSA

Chronic bladder dysfunction due to bladder disease or trauma is detrimental to affected patients as it can lead to increased risk of upper urinary tract dysfunction. Current treatment options include surgical interventions that enlarge the bladder with autologous bowel tissue to alleviate pressure on the upper urinary tract. this highly invasive procedure, termed bladder augmentation enterocystoplasty (BAE), significantly increases the risk of patient morbidity and mortality due to the incompatibility between bowel and bladder tissue. therefore, patients would significantly benefit from an alternative treatment strategy that can regenerate healthy tissue and restore overall bladder function. Previous research has demonstrated the potential of citrate-based scaffolds co-seeded with bone marrow-derived stem/progenitor cells as an alternative graft for bladder augmentation. Recognizing that contact guidance can potentially influence tissue regeneration, we hypothesized that microtopographically patterned scaffolds would modulate cell responses and improve overall quality of the regenerated bladder tissue. We fabricated microgrooved (MG) scaffolds using the citrate-based biomaterial poly (1,8-octamethylene-citrate-co-octanol) (POCO) and co-seeded them with human bone marrow-derived mesenchymal stromal cells (MSCs) and CD34+ hematopoietic stem/progenitor cells (HSPCs). MG POCO scaffolds supported MSC and HSPC attachment, and MSC alignment within the microgrooves. All scaffolds were characterized and assessed for bladder tissue regeneration in an established nude rat bladder augmentation model. In all cases, normal physiological function was maintained post-augmentation, even without the presence of stem/progenitor cells. Urodynamic testing at 4-weeks post-augmentation for all experimental groups demonstrated that bladder capacity increased and bladder compliance was normal. Histological evaluation of the regenerated tissue revealed that cell-seeded scaffolds restored nor

关键词： Guided bladder tissue regeneration Mesenchymal stem cell Hematopoietic stem cell Microtopography Neovascularization

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Effect of Aluminum on FOX-7 Structure

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火炸药学报 2019年第3期42卷 223-231,I0001页

作者： Lemi türker Middle East technical University Department of Chemistry üniversiteler

the effect of aluminum on FOX-7 structure was considered. Density functional approach at the level of unrestricted B3LYP/6-311++G(d,p) level was adopted. the model considered 1-4 aluminum atoms per FOX-7 molecule. the results show that the molecular geometries as well as many molecular orbital characteristics of FOX-7 molecule are subjected multiplicity of the composites, FOX-7 + n Al ( n =1-4). In the case of n =1-2, some conformational changes occur. In the presence of three aluminum atoms, the quartet state of the composite is stable but in the doublet state, one of the N—O bonds ruptures. As for the n =4 case the singlet and triplet states are stable but in the quintet state one of the N—O bonds cleaves. As the number of aluminum atoms increases, the HOMO-LUMO energy gap decreases generally.

关键词： FOX-7 1,1-diamino-2,2-dinitroethylene DADNE explosives aluminum DFt

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Procedural complexity independent of P2Y12 reaction unit(PRU)values is associated with acute in situ thrombosis in Pipeline flow diversion of cerebral aneurysms

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Stroke & Vascular Neurology 2018年第3期3卷 169-175页

作者： Bowen Jiang matthew t Bender Erick M Westbroek Jessica K Campos Li-Mei Lin Risheng Xu Rafael J tamargo Judy Huang Geoffrey P Colby Alexander L Coon Department of Neurosurgery Johns Hopkins University School of MedicineBaltimoreMarylandUSA Department of Neurosurgery University of CaliforniaIrvine School of MedicineOrangeCaliforniaUSA Department of Neurosurgery University of CaliforniaLos AngelesLos AngelesCaliforniaUSA

background Acute in situ thrombosis is an ischaemic phenomenon during Pipeline embolisation device(PED)procedures with potentially high morbidity and *** is controversy regarding the role of platelet function testing with P2Y12 assay as a predictor of intraprocedural thromboembolic *** is limited knowledge on whether procedural complexity influences these *** Data were collected retrospectively on 742 consecutive PED cases at a single *** with intraprocedural acute thrombosis were compared with patients without these *** A cohort of 37 PED cases with acute in situ thrombosis(mean age 53.8 years,mean aneurysm size 8.4 mm)was matched with a cohort of 705 PED cases without intraprocedural thromboembolic events(mean age 56.4 years,mean aneurysm size 6.9 mm).All patients with in situ thrombosis received intra-arterial and/or intravenous *** two groups were evenly matched in patient demographics,previous treatment/subarachnoid hemorrhage(SAH)and aneurysm *** was no statistical difference in postprocedural P2Y12 reaction unit(PRU)values between the two groups,with a mean of 156 in the in situ thrombosis group vs 148 in the control group(p=0.5894).Presence of cervical carotid tortuosity,high cavernous internal carotid artery grade,need for multiple PED and vasospasm were not significantly different between the two *** in situ thrombosis group had statistically significant longer fluoroscopy time(60.4 vs 38.4 min,ption exposure(3476 vs 2160 mGy,ptes of adjunctive coiling(24.3% vs 8.37%,p=0.0010)and higher utilisation of balloon angioplasty(37.8% vs 12.2%,pthe in situ thrombosis cohort had higher incidence of major and minor stroke,intracerebral haemorrhage and length of *** Predictors of procedural complexity(higher radiation exposure,longer fluoroscopy time,adjunctive coiling and need for balloon angioplasty)are asso

关键词： P2Y12 matched balloon

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Effect of Magnesium Atom on CL-20------A DFt treatment

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火炸药学报 2017年第6期40卷 17-22页

作者： Lemi türker Department of Chemistry Universiteler Middle East Technical University Ankara Turkey 06231

the effect of magnesium atom on 2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaisowurtizane(HNIW,CL-20)explosive is considered within the constraints of density functional theory at the level of B3LYP/6-31++G(d,p).the Mg atom transfers some electron population to CL-20and one of the nitro groups linked to 6-membered piperazine ring system(base)is expelled in the prenitrite *** total Mulliken charges on the NO2group reveals that the respective nitramine bond in CL-20is the most susceptible one to *** calculated IR and UV-VIS spectra are *** effect of Mg atom on the molecular orbital energies,especially the HOMO and LUMO has been *** of the interfrontier molecular orbital energy gap(Δε)in the composite system ***,the composite system is more susceptible to impact compared to CL-20.

关键词： CL-20 hexanitro hexaazaisowurtizane explosives magnesium density functional theory

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Effect of size on biaxial flexural strength for cement-based materials by using a triangular plate method

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Frontiers of Structural and Civil Engineering 2022年第8期16卷 1017-1028页

作者： Hakan t tURKER Department of Civil Engineering Bursa Uludag UniversityBursa 16059Turkey

the effect of size on the biaxial flexural strength(BFS)of Portland cement mortar was investigated by using the recently proposed triangular plate method(tPM).An experimental program was conceived to study the size effect by keeping a constant water-cement ratio of 0.485,cement-sand ratio of 1:2.75,and using unreinforced triangular mortar plates of five different thicknesses and seven different side *** BFS of the produced specimens was tested,and variations of BFS depending on specimen thickness and side length were *** results indicated that increases in triangular plate specimen side length and specimen thickness led to a decrease in the BFS of Portland cement *** effect of specimen length increase on BFS was more significant than on the effect of the specimen *** variations in specimens’thickness indicated a deterministic type I size effect,while the variations in specimens’length showed an energetic-statistical type I size effect.

关键词： testing apparatus&methods plain concrete tensile properties biaxial flexural strength triangular plate method

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Interaction of 1,3,3-trinitroazetidine(tNAZ)and Zinc——A DFt treatise

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火炸药学报 2020年第5期43卷 477-483,I0001页

作者： Lemi türker Middle East technical University Department of ChemistryüniversitelerEskisehir Yolu No.106800 ankaya/AnkaraTurkey

In order to investigate whether zinc atom is compatible with 1, 3, 3-trinitroazetidine(tNAZ) structure, tNAZ+Zn and 2 tNAZ+Zn composite systems have been considered within the constraints of density functional theory at the level of B3 LYP/6-31++G(d,p) and ωB97 X-D/6-31++G(D,P). In the case of tNAZ+Zn composite the both level of calculations resulted that one of the C-NO2 bonds of tNAZ undergoes bond cleavage. However, as the zinc content decreases by increasing the tNAZ content, C-NO2 bond elongation considerably decreases, although it is still longer than the similar bonds in 2 tNAZ+Zn composite in which zinc, by weight, is 7.14%. In all the cases the zinc atom acquires positive charge. the results indicate that the interfrontier molecular orbital energy gaps(HOMO-LUMO energy difference) of the composites decrease as the zinc content decreases.

关键词： quantum chemistry 1,3,3-trinitroazetidine tNAZ explosive zinc DFt

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Quire Interaction of Certain Nitramine type Explosives with Proton--A DFt Study

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火炸药学报 2017年第1期40卷 1-6页

作者： Lemi türker Department of Chemistry Middle East technical University Ankara Turkey 06231

the composites of certain nitramine type explosives,tEtRYL,RDX and EDNA,with proton in vacuum have been considered within the constraints of density functional theory at the level of B3LYP/6-31++G(d,p)(restricted and unrestricted).the results indicate that unexpectedly hydrogen molecule production occurs by the interaction of proton and a hydrogen of CH3(tEtRYL)and CH2(RDX and EDNA)*** a result,a carbocation is generated on the explosive ***,tEtRYL which potentially has many protonation sites were investigated in more detail in vacuum and aqueous *** data reveals that the composite system(tEtRYL+proton)is less stable than tEtRYL protonated on nitramine NH or oxygen of the nitro groups.

关键词： nitramines tEtRYL RDX EDNA proton DFt

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