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Journal of Materials Science & Technology 2021年第28期87卷 196-206页

作者： A.G.Mochugovskiy n.yu.Tabachkova M.Esmaeili Ghayoumabadi V.V.Cheverikin A.V.Mikhaylovskaya national University of Sciences and Technology“MISIS” 119049Leninskiy Ave.4MoscowRussia Prokhorov General Physics Institute of the Russian Academy of Sciences MoscowRussia

Dispersoid hardening is a key factor in increasing the recrystallization resistance and mechanical strength of non-heat treatable aluminum-based *** and Zr are the main elements that form dispersoids in commercial Al-based *** this work,the annealing-induced precipitation behavior,the grain structure,and the mechanical properties of Al-3.0 Mg-1.1 Mn and Al-3.0 Mg-1.1 Mn-0.25 Zr alloys were *** microstructure and the mechanical properties were significantly affected by annealing regimes after casting for both *** research demonstrated a possibility to form high-density distributed quasicrystalline-structured I-phase precipitates with a mean size of 29 nm during low-temperature annealing of as-cast *** manganese-bearing precipitates of I-phase increased recrystallization resistance and significantly enhanced the mechanical strength of the alloys *** estimated strengthening effect owing to I-phase precipitation was 150 *** to the formation of L1_(2)-structured Al3Zr dispersoids with a mean size of 5.7 nm,additional alloying with Zr increased yield strength by about 90 *** L1_(2)-phase strengthening effect was estimated through the dislocation bypass looping and shearing mechanisms.

关键词： Aluminum alloy Quasicrystals Dispersoid hardening Recrystallization Mechanical properties

Biochemical Characterization of Uracil-DnA Glycosylase from Pyrococcus furiosus

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Chemical Research in Chinese Universities 2012年第3期28卷 477-482页

作者： L1n Li-bo LIU yu-fen LIU Xi-peng LIU Jian-hua Key Laboratory of Microbial Metabolism School of Life Sciences&BiotechnologyShanghai Jiaotong UniversityShanghai 200240P.R.China

We report the characterization of a uracil-DnA glycosylase（UDG） from the hyperthermophilic archaea Pyrococcus furiosus（P, furiosus）. P. furiosus UDG（PfUDG） has high sequence similarity to the families IV and V UDGs（thermostable UDG family and PaUDG-b family）. PfUDG excises uracil from various DnA substrates with the following order： U/T=U/C〉U/G=U/AP=U/-〉U/U=U/I=U/A. The optimal temperature and pH value for uracil exci- sion by PfUDG are 70 ℃ and 9.0, respectively. The removal of U is inhibited by the divalent ions of Fe, Ca, Zn, Cu, Co, ni and Mn, as well as a high concentration of naC1. The phosphorothioates near uracil strongly inhibit the exci- sion of uracil by PfUDG. Interestingly, pfuDnA（Pyrococcusfuriosus DnA） polymerase, which tightly binds the ura- cil-carrying oligonucleotide, does not inhibit the excision by ***, suggesting PfUDG in vivo functions as the re- pair enzyme to excise uracil damage in genome.

关键词： Pyrococcus furiosus(P furiosus) Uracil DnA glycosylase(UDG) Pyrococcus furiosus DnA polymeras Uracil repair in hyperthermophile

Gold mineralisation and orogenic metamorphism in the Lena province of Siberia as assessed from Chertovo Koryto and Sukhoi Log deposits

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Geoscience Frontiers 2016年第3期7卷 453-481页

作者： Marina A.yudovskaya Vadim V.Distler Vsevolod yu.Prokofiev nickolay n.Akinfiev Institute of Geology of Ore Deposits PetrographyMineralogy and Geochemistry RAS EGRI University of the Witwatersrand

The Chertovo Koryto gold deposit（80 t Au at 1.84 g/t） in the Lena world-class province,Siberia,is hosted in a metamorphosed sequence of the Paleoproterozoic Mikhailovsk Formation that comprises the oldest black shale strata of the Baikal-Patom *** mineralisation is confined to the thrust zone complicated with a conjugate anticline fold,zones of shearing and *** struaural position of the mineralisation is similar to that at the giant Sukhoi Log deposit in the neighbouring Mama-Bodaibo *** the latter,the isotope age data suggest that Khomolkho black shales,hosts to Sukhoi Log mineralisation,are of Ediacaran age and underwent prograde metamorphism during early *** geochemical composition of the terrigenous rocks that host Sukhoi Log,Chertovo Koryto,and a number of other deposits at the various stratigraphic levels throughout the Proterozoic sequence have much in *** do not show elevated metal contents above the common black shale abundances,except for Au and As,which is at variance with the accepted view on diagenetic enrichment of black shales in the Lena *** occurrence of sagenitic rutile in quartz and chlorite pseudomorphs after biotite and other petrographic observations provide evidence on a retrograde nature of the metamorphic mineral assemblages in the Mikhailovsk *** sulphides are pyrrhotite and arsenopyrite with very minor pyrite at Chertovo Koryto,whereas pyrite is the predominant sulphide in the Sukhoi Log *** inclusion data on both deposits emphasise a high-temperature nature of the mineralisation albeit revealing great contrast in the fluid *** Log mineralisation was formed at mixing between low-salinity aqueous solutions and dense gaseous carbonic fluids,which facilitated effective gold scavenging and precipitation,as demonstrated by thermodynamic *** precursory devolatilisation of the Mikhailovsk sediments at the prograde stage results in the paucity of gaseous carbon

关键词： Gold Black shales Orogenic metamorphism Orogenic fluid Sukhoi Log Chertovo Koryto

Tonalites and plagiogranites of the Char suture-shear zone in East Kazakhstan:Implications for the Kazakhstan-Siberia collision

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Geoscience Frontiers 2016年第1期7卷 141-150页

作者： M.L.Kuibida I.yu.Safonova P.V.Yermolov A.G.Vladimirov n.n.Kruk S.Yamamoto lnstitute of Geology and Mineralogy SB RAS Koptyuga ave.3Novosibirsk630090Russia novosibirsk State University Pirogova St.2Novosibirsk630090Russia IPCOn Joint Venture Academy of Sciences of Kazakhstanlppodromnaya 5100019KaragandaKazakhstan Tomsk State University Lenina St.36Tomsk634050Russia University of Tokyo MeguroTokyo153-8902Japan

The paper presents first Ue Pb zircon ages and geochemical data from Carboniferous granitoids（tonalites and plagiogranites） of the Char sutureeshear zone in East Kazakhstan, which is located in the northwestern Central Asian Orogenic Belt（CAOB）. The study included analysis of geological setting, major and trace elements, and rock petrogenesis. The Char tonalites and plagiogranites occur as nW-striking linear chains inside Visean serpentinite mélange. Petrographycally, the tonalites show signs of syntectonic deformation, and the plagiogranites are less deformed suggesting their later intrusion. The tonalites yielded a LA-ICP-MS zircon age of ca. 323 Ma, i.e. exactly at the boundary between the early and late Carboniferous. Compositionally, the tonalites and plagiogranites are characterized, respectively, by high SiO2（67-70 and 73-74 wt.%） and Al2O3（17-19 and 14-15 wt.%）, Sr/Y 〉 40 and low Yb=0.2-0.5 *** multi-element patterns show clear nb-Ta negative anomalies. The low nb/Ta ratios（7-15） and Zr（114-191 ppm） suggest a MORB-type protolith（amphibolite） with subchondritic nb/Ta（8-17） and low Zr（1-72 ppm）. The low contents of K and Rb suggest weak assimilation of the melts by island arc felsic crust. The subchondritic nb/Ta ratios exclude their derivation by the melting of subducted/dehydrated MORB. We argue that the Char high-Al tonalites and plagiogranites formed by the melting of hydrated MORB at the base of the mafic lower crust at pressures of 10-15 kbar. The occurrences of the Char tonalites and plagiogranites inside the Visean serpentinite mélange overlapped by Serpukhovian conglomerates, their alignment parallel to deformation zones, and their geochemical features suggest their origin by the melting of mafic lower crust in relation to the collision of the Siberian and Kazakhstan continents.

关键词： Earlyelate Carboniferous boundary nW Central Asian Orogenic Belt U-Pb ages Whole-rock geochemistry Petrogenesis Mafic crust melting

Can gene editing reduce postharvest waste and loss of fruit, vegetables, and ornamentals?

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Horticulture Research 2021年第1期8卷 51-71页

作者： Emma n.Shipman Jingwei yu Jiaqi Zhou Karin Albornoz Diane M.Beckles Department of Plant Sciences University of CaliforniaDavisCA 95616USA Plant Biology Graduate Group University of CaliforniaDavisCA 95616USA Graduate Group of Horticulture&Agronomy University of CaliforniaDavisCA 95616USA Departamento de Produccion Vegetal Universidad de ConcepcionRegion del BioBioConcepcionChile

Postharvest waste and loss of horticultural crops exacerbates the agricultural problems facing humankind and will continue to do so in the next *** and vegetables provide us with a vast spectrum of healthful nutrients,and along with ornamentals,enrich our lives with a wide array of pleasant sensory *** commodities are,however,highly *** 33%of the produce that is harvested is never consumed since these products naturally have a short shelf-life,which leads to postharvest loss and *** loss,however,could be reduced by breeding new crops that retain desirable traits and accrue less damage over the course of long supply *** gene-editing tools promise the rapid and inexpensive production of new varieties of crops with enhanced traits more easily than was previously *** aim in this review is to critically evaluate gene editing as a tool to modify the biological pathways that determine fruit,vegetable,and ornamental quality,especially after *** provide brief and accessible overviews of both the CRISPR-Cas9 method and the produce supply ***,we survey the literature of the last 30 years,to catalog genes that control or regulate quality or senescence traits that are"ripe"for gene ***,we discuss barriers to implementing gene editing for postharvest,from the limitations of experimental methods to international *** conclude that in spite of the hurdles that remain,gene editing of produce and ornamentals will likely have a measurable impact on reducing postharvest loss and waste in the next 5-10 years.

关键词： crops editing harvest

On THE GEnERAL ALGEBRAIC InVERSE EIGEnVALUE PROBLEMS

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Journal of Computational Mathematics 2004年第4期22卷 567-580页

作者： yu-haiZhang DepartmentofMathematics ShandongUniversityJinan250100China

A number of new results on sufficient conditions for the solvability and numerical algorithms of the following general algebraic inverse eigenvalue problem are obtained: Given n+1 real n×n matrices A = (aij), Ak=(a^(k)ij)(k=1,2,...,n) and n distinct real numbers λ1, λ2, ..., λn, find n real numbers cl, c2,..., cn such that the matrix A(c)=A+∑^nk=1 ckAk has eigenvalues λ1, λ2,...,λn.

关键词： Eigenvalue problem Inverse problem Linear algebra

Unified Limits and Large Deviation Principles forβ-Laguerre Ensembles in Global Regime

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Acta Mathematica Sinica,English Series 2023年第7期39卷 1271-1288页

作者： yu Tao MA School of Mathematical Sciences&Laboratory of Mathematics and Complex Systems of Ministry of Education Beijing Normal UniversityBeijing 100875China

Let(λ_(1),...,λ_(n)) be β-Laguerre ensembles with parametersβ,p,n and μ_(n):=1/n∑^(n)_(i=1)δ_(Xi) with for 1≤i≤*** this paper,asβvaries and satisfies lim_(n→∞)log n/βn=0,we offer a modified Marchenko-Pastur,law or semicircle law as the weak limits for the sequence μ_(n) when lim_(n→∞)n/p=γ∈(0,1]or lim_(n→∞)n/p=0,*** recovers some well-known ***,we give a full large deviation principle of μ_(n) with speed βn^(2) and good rate function I_(γ) under the same condition to characterize the speed of the *** minimizer of I_(γ) is a modified Marchenko-Pastur law forγ∈(0,1]and the semicircle law forγ=0.

关键词： β-Laguerre ensemble large deviation principle empirical measure semicircular law Marchenko–Pastur law

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Synthesis,Structure and Magnetic Properties of novel Carboxylato-bridged Pentanuclear Copper(Ⅱ)-Lanthanoid(Ⅲ)Complexes

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Chemical Research in Chinese Universities 1998年第3期14卷 8-13页

作者： TOnG Ming-liang WU yu-luan CHEn Xiao-ming SUn Zi-ming David n.Hendrickson Department of Chemistry Zhongshan UniversityGuangzhou510275 Department of Chemistry-0358 University of California at San DiegoLa JollaCA92093USA

Six novel pentanuclear complexes [Cu 3Ln 2(ClCH 2CO 2) 12 (H 2O) 8]·2H 2O (Ln=La, Pr, Sm, Gd, Dy, or Er) were synthesized by the reaction of chloroacetic acid with Cu and Ln ions in aqueous solutions. The X ray crystallography established the structure of the Gd complex, which contains a pair of quadruply acetato bridged CuGd dinuclear subunits, and each of them is linked to the central Cu atom by a single acetato bridge. The coordination sphere of each Gd atom is completed by three aqua ligands [Gd-O=0.242 8(5)-0.244 4(4) nm] to form an 8 coordinated distorted square antiprism. The central Cu atom is coordinated by two oxygen atoms from the two bridging acetato groups and two oxygen atoms from the two monodentate acetato groups in a slightly distorted square planar fashion, while each terminal Cu atom is coordinated by the four acetato oxygen atoms at the basal plane and an aqua ligand at the apical position to form a square pyramid. The variable temperature (4 320 K) magnetic susceptibility data of the Gd complex were measured, and fitted to the Curie Weiss law with C =16.38 K cm 3·mol -1 and θ =-1.55 K, indicating very weak antiferromagnetic interaction.

关键词： Heterometallic complex Copper(Ⅱ) Lanthanoid(Ⅲ) Antiferromagnetic interaction

基于嵌入式离散裂缝建模的Eagle Ford页岩油复杂水力裂缝综合表征

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石油勘探与开发 2021年第3期48卷 613-619页

作者： FIALLOS Mauricio MORALES Adrián yu Wei MIAO Jijun 德克萨斯大学奥斯汀分校西德布莱德石油与地质工程系德克萨斯78712美国 SimTech有限责任公司休斯顿77494美国切萨皮克(Chesapeake)公司俄克拉荷马73154美国

使用嵌入式离散裂缝建模(EDFM)方法优化具有复杂裂缝系统的油藏的数值模拟,完善了前人的Eagle Ford页岩油综合描述技术。根据裂缝支撑类型对具有100000多个裂缝面的复杂裂缝系统进行分类后,对井底流压进行了历史拟合,对油田产量进行了预... 详细信息

使用嵌入式离散裂缝建模(EDFM)方法优化具有复杂裂缝系统的油藏的数值模拟,完善了前人的Eagle Ford页岩油综合描述技术。根据裂缝支撑类型对具有100000多个裂缝面的复杂裂缝系统进行分类后,对井底流压进行了历史拟合,对油田产量进行了预测,以更深入地了解复杂裂缝支撑效果对产量的影响。在为不同支撑类型裂缝组分配不同的压实曲线后估算的压降表明,如果采用EDFM方法而不是非结构网格方法进行裂缝建模和筛选,裂缝模型表达更精确,有效波及面积可能会小于非结构网格方法。方法优化后,能够将EDFM与第三方裂缝扩展模拟器自动耦合,同时考虑支撑剂强度沿复杂裂缝系统的变化。该方法能够从裂缝评价和多个全井眼的拟三维裂缝扩展结果中准确地模拟复杂的裂缝延伸和井间干扰,从而更准确地评价完井效果。

关键词：嵌入式离散裂缝建模复杂裂缝水力裂缝裂缝网络油藏模拟页岩油

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急性主动脉夹层合并2型糖尿病患者危险因素、预后及快速筛查研究

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中国全科医学 2025年第9期28卷 1100-1105页

作者：黄璐捷张小英俞莎莎浙江省宁波市医疗中心李惠利医院老年医学科

背景急性主动脉夹层（AAD）合并2型糖尿病的发病率呈上升趋势，然而，关于其危险因素和预后的研究较少。因此，积极寻求临床一种简便且有效的诊断工具已成为研究的重点。目的分析AAD合并2型糖尿病患者危险因素、预后及快速筛查方法。方... 详细信息

背景急性主动脉夹层（AAD）合并2型糖尿病的发病率呈上升趋势，然而，关于其危险因素和预后的研究较少。因此，积极寻求临床一种简便且有效的诊断工具已成为研究的重点。目的分析AAD合并2型糖尿病患者危险因素、预后及快速筛查方法。方法选取2016年1月—2022年10月宁波市医疗中心李惠利医院收治的168例AAD患者为研究对象，使用主动脉夹层检测风险评分（ADD-RS）量表对患者进行初筛分诊。选用主动脉CT血管造影（CTA）检查结果作为AAD确诊的“金标准”，比较主动脉CTA确诊结果与ADD-RS量表的初筛结果。根据是否合并2型糖尿病分为糖尿病组和非糖尿病组，收集两组的一般资料，采用多因素Logistic回归分析探讨AAD患者合并2型糖尿病的危险因素；比较两组的短期预后及疼痛评分。采用多因素Cox回归分析AAD患者短期预后的影响因素，采用受试者工作特征（ROC）曲线分析ADD-RS量表对AAD合并2型糖尿病的筛查价值。结果本研究糖尿病组59例，非糖尿病组109例。多因素Logistic回归分析显示，增龄（OR=1.088,95%CI=1.042～1.136,P0.05）；两组30 d死亡率分别为3.39%和3.67%，差异无统计学意义（P>0.05）。多因素Cox回归分析显示高血压不是影响AAD患者短期预后的独立因素（HR=0.673,95%CI=0.094～4.791,P>0.05）。糖尿病组的ADD-RS为1(1)分，高于非糖尿病组的1(2)分（Z=-4.640,P<0.001）；糖尿病组的高风险及中风险患者均多于非糖尿病组（Z=2.309,P=0.021）;ADD-RS量表筛查AAD合并2型糖尿病的ROC曲线下面积为0.706(95%CI=0.634～0.779)。结论 AAD合并2型糖尿病患者的危险因素有年龄增高、BMI≥25 kg/m2、冠心病、高脂血症、LVEF升高，且ADD-RS量表在AAD合并2型糖尿病患者的风险评估中具有较高的临床筛查价值。

关键词：急性主动脉夹层糖尿病,2型主动脉夹层检测风险评分快速诊治

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