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Primitive to conventional geometry projection for efficient phonon transport calculations

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npj Computational Materials 2023年第1期9卷 365-371页

作者： Xun Li Simon thébaud Lucas Lindsay Materials Science and Technology Division Oak Ridge National LaboratoryOak RidgeTNUSA Univ Rennes INSA RennesCNRSInstitut FOTON-UMR 6082RennesFrance

the primitive Wigner-Seitz cell and corresponding first Brillouin zone(FBZ)are typically used in calculations of lattice vibrational and transport properties as they contain the smallest number of degrees of freedom and thus have the cheapest computational ***,in complex materials,the FBZ can take on irregular shapes where lattice symmetries are not ***,conventional cells(with more atoms and regular shapes)are often used to describe materials,though dynamical and transport calculations are more *** we discuss an efficient anharmonic lattice dynamic method that maps conventional cell dynamics to primitive cell dynamics based on translational *** symmetries have not been utilized in typical lattice dynamical *** leads to phase interference conditions that act like conserved quantum numbers and a conservation rule for phonon scattering that is hidden in conventional dynamics which significantly reduces the computational *** demonstrate this method for phonon transport in a variety of materials with inputs from first-principles calculations and attribute its efficiency to reduced scattering phase space and fewer summations in scattering matrix element calculations.

关键词： phonon conventional primitive

Phase Evolution during the Sintering of Submicron Ti(C,N)-Based Cermets

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Rare Metals 2001年第4期20卷 248-254页

作者： Li, ch Xiong, WH Yu, LX Huazhong Univ Sci & Technol State Key Lab Plast Forming Simulat & Die & Mould Wuhan 430074 Peoples R China

the submicron powder mixtures of TiC-TiN-WC-Mo-C-Ni sintered at 1400degreesC or below in vacuum were studied by X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) analyses. the results showed that Mo2C formed at 800degreesC or below. Both WC and Mo2C disappeared at 1200degreesC, and TiN disappeared at 1250degreesC. In addition, the variations of lattice constants of the titanium carbonitride and nickel binder phase with sintering temperature were experimentally obtained, and the reason was analyzed.

关键词： submicron cermet phase sintering

Peraluminous A-type granites formed through synchronous fractionation,magma mixing,mingling,and undercooling:evidence from microgranular enclaves and host Mesoproterozoic Kanigiri granite pluton,Nellore Schist Belt,southeast India

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Acta Geochimica 2023年第4期42卷 603-636页

作者： ch.Narshimha Santosh Kumar Department of Geology Centre of Advanced StudyKumaun UniversityNainital 263001India

the field and microstructural features coupled with mineral chemical data from microgranular enclave(ME)and host Mesoproterozoic Kanigiri granite(KG)pluton of Nellore Schist Belt(NSB),Southeastern India,have been documented in order to infer the likely processes responsible for the origin and evolution of ME and host KG *** ME and host KG bear the same mineral assemblages barring the KG which does not contain amphibole;however,they are modally *** ME in KG is originated due to multiple intrusions of ME magmas into the crystallizing host KG magma *** and textural features indicate the dynamic magma flow,mingling,and undercooling of the ME against a relatively cooler surface of host KG *** presence of NSB country rock xenoliths and its diffuse boundaries suggest the intrusive relation and marginal assimilation by the intruding KG *** occasional cumulate texture in the ME appears to have formed by the accumulation of early-formed minerals that crystallized rapidly in the ME magma *** ME shows the magmatically deform features developed due to the flowage and erosion by the subsequent intrusions of ME magma pulses into the crystallizing host KG magma *** ME amphiboles show unusual composition as ferro-edenitic hornblende to potassian-hastingsitic hornblende,that crystallized in the subalkaline-alkaline transition,low fO_(2)(reducing to mildly oxidizing)*** unusual extremely low Mg/Mg+Fe^(t)=0.015(avg.)of ME amphiboles may be related to the changing physico-chemical(P,T,fO_(2),and H_(2)O)condition of the ME magma or they might have crystallized in equilibrium with more evolved KG *** KG(FeOt/MgO=37.04,avg.)and ME(FeO~t/MgO=77.72,avg.)biotites are siderophyllite,and buffered between QFM and NNO syn-crystallizing in the water undersaturated(H_(2O)≈3.58 wt.%in KG;≈3.53wt.%in ME),alkaline anorogenic(A-type)host magmas that were emplaced at mid-crustal(4–5 kbar;17 km)***,microtextural and mineral

关键词： Enclave Kanigiri granite Magma mixing-fractionation Nellore schist belt SE India

Photophysical Behaviors of Azobenzene in Solvent-Swollen Nafion Membranes

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chinese chemical Letters 1996年第10期7卷 944-947页

作者： Guan, JQ Tung, ch ACAD SINICA INST PHOTOG CHEMBEIJING 100101PEOPLES R CHINA

the fluorescence from azobenzene (AB) molecule incorporated into water-swollen Nafion in acid form was observed at room temperature for the first time. the incorporation process was investigated by UV absorption. the plot of the concentration of AB in Nafion vs. the soaking time shows that the adsorption process is diffusion-controlled, and the apparent diffusion coefficient (D) was determined to be 7.6x10(-10) cm(2)s(-1). these results are attributed to the fact that AB molecules are located in the fluorocarbon/water interface of the Nafion membranes and are protonated. In methanol-swollen Nafion membranes, AB fails to fluoresce because it is located at the methanol pool enclosed by the cluster networks.

关键词： Photophysical Behaviors of Azobenzene in Solvent-Swollen Nafion Membranes

DNA damage and neurodegeneration:the unusual suspect

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Neural Regeneration Research 2017年第9期12卷 1441-1442页

作者： Daniel stein Debra Toiber Department of Life Sciences Ben-Gurion University of the Negev the Zlotowski Center for Neuroscience Ben-Gurion University of the Negev

Neurodegenerative diseases are caused by the loss of neuro- nal cells. As neurons deteriorate, a patient may experience relatively mild symptoms such as failing to name objects and people. However, with the progression of the disease, symp- toms worsen resulting in loss of independence and a sense of＂loss of oneself＂. Finally, the patient dies from a variety of complications.

关键词： DNA damage and neurodegeneration:the unusual suspect

Semiconductor photoinduced cycloreversion of the dimer of methyl 2-naphthoate

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chinese Journal of chemistry 1997年第3期15卷 260-264页

作者： Tung, ch Ying, YM Institute of Photographic chemistry Chinese Academy of Sciences Beijing 100101 China [*]Institute of Photographic chemistry Chinese Academy of Sciences Beijing 100101 China

the dimer of methyl 2-naphthoate (I) has been found to undergo efficient cycloreversion to its monomer, methyl naphthalene-2-carboxylate (2) on illuminated ZnO and TiO2 but not on CdS. An electron transfer and cation radical chain mechanism is proposed. Quantum yields, solvent effect. the role of oxygen, and the quenching of the reaction were investigated, and were consistent with the proposed mechanism.

关键词： semiconductor photoinduced cycloreversion electron transfer

Photosensitized Cycloreversion of Cage Compound via Triplet Energy Transfer

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chinese chemical Letters 1996年第9期7卷 794-796页

作者： Tung, ch Ying, YM chINESE ACAD SCI INST PHOTOG CHEMBEIJING 100101PEOPLES R CHINA

Several triplet sensitizers were found to be able to photosensitize cycloreversion of the photodimer (1) of methyl naphthalene-2-carboxylate. With the increase of the donor's triplet energy, the quantum yield of the i... 详细信息

关键词： Photosensitized Cycloreversion of Cage Compound via Triplet Energy Transfer

‘Smart’copycat mutual funds:on the performance of partial imitation strategies

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Financial Innovation 2022年第1期8卷 2508-2538页

作者： Roberto stein Department of Finance University of Nebraska-Lincoln730 N 14th StLincolnNE 68588USA

Using a novel measure of stock-level trade imitation,we uncover‘smart’copycats:fund managers that use their own information when beneficial,and otherwise imitate other managers’better *** to previous research,we find that these partial imitation strategies lead to ***‘Copycat Score’combines the propensity to imitate and to lead *** at the high and low ends of the score outperform all *** Copycat Score is persistent in time,related to other measures of skill,and a good predictor of fund *** conclude that smart copycatting is another skill of successful fund managers.

关键词： Copycat portfolios Mutual funds Portfolio holdings Fund performance Fund manager skill

Can a dam type of an alpine lake be derived from lake geometry?A negative result

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Journal of Mountain Science 2021年第3期18卷 614-621页

作者： Adam EMMER Vojtěch CURIN University of Graz Institute of Geography and Regional ScienceCascade|The Mountain Processes and Mountain Hazards GroupGraz 8010Austria Czech Academy of Sciences Prague 16500Czechia Global change Research Institute Czech University of Life Sciences PragueFaculty of Environmental SciencesBrno 60300Czechia

Glacial lake outburst floods(GLOFs)represent one of the most serious hazard and risk in deglaciating high mountain regions worldwide and the need for GLOF hazard and risk assessment is *** a consequence,numerous region-and nation-wide GLOF assessment studies have been published *** studies cover large areas and consider hundreds to thousands of lakes,prioritizing the hazard posed by ***,certain simplification is required for executing such studies,often resulting in neglecting qualitative characteristics which would need manual *** lake dam types(e.g.,bedrock-dammed,moraine-dammed)are often not distinguished,despite they control GLOF mechanism(dam overtopping/dam breach)and thus GLOF *** this study,we explore the potential of easily measurable quantitative characteristics and four ratios to approximate the lake dam *** dataset of 851 lakes of the Cordillera Blanca suggests that while variances and means of these characteristics of individual lake types differ significantly(F-test,t-test),value distribution of different geometrical properties can’t be used for the originally proposed purpose along the *** only promising results are obtained for extreme values(selected bins)of the *** instance,the low width to length ratio indicates likely morainedammed lake while the high value of ratio indicating round-shape of the lake indicates increased likelihood of bedrock-dammed ***,we report a negative result of our experiment since there are negligible differences of relative frequencies in most of the bins along the spectra.

关键词： Alpine lake High mountain lake GLOFs Glacial lake Moraine-dammed Bedrock-dammed Negative result Cordillera Blanca