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Mecha.ica.ly Driven a.loying a.d Structura. Evolution of Na.ocrysta.line Fe_(60)Cu_(40) Powder

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Journa. of materia.s Science & Technology 1997年第4期13卷 354-358页

作者： Yua.da.DONG a.d Xueming ma(School of materia.s Science a.d Engineering, Sha.gha. University, Sha.gha. 200072, China.Yua.zheng Ya.G(Dept. of Mecha.ica. Engineering(2), South China.University of Technology, Gua.gzhou 510641, China.Fa.gxin LIU a.d Genmia. wa School of materia.s Science a.d Engineering Shanghai University Shanghai 200072 China Dept. of Mecha.ica. Engineering(2) South China University of Technology Guangzhou 510641 China La.. of Structure a.a.ysis University of Science and Technology of China Hefei 230026 China

Highly supersa.ura.ed na.ocrysta.line fcc Fe60Cu40 a.loy ha. been prepa.ed by mecha.ica. a.loying of elementa. powders. The pha.e tra.sformation is monitored by X-ra. diffra.tion (XRD),Mossba.er spectroscopy a.d extended X-ra. a.sorption fine structure (EXa.S). The powder obta.ned a.ter milling is of single fcc structure with gra.n size of na.ometer order. The Mossba.er spectra.of the milled powder ca. be fitted by two subspectra.whose hyperfine magnetic fields a.e 16 ma/m a.d 20 ma/m while tha. of pure Fe disa.pea.ed. EXa.S results show tha. the ra.ia. structure function (RSF) of Fe K-edge cha.ged dra.tica.ly a.d fina.ly beca.e simila. to tha. of reference Cu K-edge, while tha. of Cu K-edge nea.ly keeps uncha.ged in the process of milling. These imply tha. bcc Fe rea.ly tra.sforms to fcc structure a.d a.loying between Fe a.d Cu occurs truly on a. a.omic sca.e. EXa.S results indica.e tha. iron a.oms tend to segrega.e a. the bounda.ies a.d Cu a.oms a.e rich in the fcc la.tice. a.nea.ing experiments show tha. the Fe a.oms a. the interfa.es a.e ea.y to cluster to α-Fe a. a.lower tempera.ure, wherea. the iron a.oms in the la.tice will form γ-Fe first a. tempera.ure a.ove 350℃, a.d then tra.sform to bcc Fe

关键词： Mecha.ica.ly Driven a.loying a.d Structura. Evolution of Na.ocrysta.line Fe ma Cu Powder Figure

Theoretica. study on the mecha.ism of sulfur migra.ion to ga. in the pyrolysis of benzothiophene

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Frontiers of Chemica. Science a.d Engineering 2023年第3期17卷 334-346页

作者： Ji Liu Shua.g-Wei Ya.g Wei Zha. Yu-Long Wu Bin Hu Si-Ha. Hu Sha.-Wei ma Qia.g Lu Na.iona. Engineering Resea.ch Center of New Energy Power Genera.ion North China Electric Power UniversityBeijing 102206China Suzhou Institute of North China.Electric Power University Suzhou 215000China Institute of Nuclea. a.d New Energy Technology Tsinghua UniversityBeijing 100084China School of Chemistry a.d Chemica. Engineering Xinjiang UniversityUrumqi City 830046China

The relea.e a.d control of sulfur species in the pyrolysis of fossil fuels a.d solid wa.tes ha.e a.tra.ted a.tention ***,thiophene deriva.ives a.e importa.t intermedia.es for the sulfur ga. relea.e from orga.ic sulfur,but the underlying migra.ion mecha.isms remain ***,the mecha.ism of sulfur migra.ion during the relea.e of sulfur-conta.ning ra.ica.s in benzothiophene pyrolysis wa. explored through qua.tum chemistry *** C_(1)-to-C_(2)H-tra.sfer ha. the lowest energy ba.rier of 269.9 kJ·mol-1 a.d the highest ra.e consta.t a. low tempera.ures,while the eleva.ed tempera.ure is beneficia. for C−S bond homolysis.2-Ethynylbenzenethiol is the key intermedia.e for the formation of S a.d SH ra.ica.s with the overa.l energy ba.riers of 408.0 a.d 498.7 kJ·mol-1 in fa.ora.le *** genera.ion of CS ra.ica.s is rela.ively difficult beca.se of the high energy ba.rier(551.8 kJ·mol-1).However,it ca. be significa.tly promoted by high tempera.ures,where the ra.e consta.t exceeds tha. for S ra.ica. genera.ion a.ove 930°***,the strong competitiveness of S a.d SH ra.ica.s results in a.unda.t H2 S during benzothiophene pyrolysis,a.d the high tempera.ure is more beneficia. for CS2 genera.ion from CS *** study la.s a.founda.ion for elucida.ing sulfur migra.ion mecha.isms a.d furthering the development of pyrolysis techniques.

关键词： benzothiophene sulfur migra.ion pyrolysis density functiona. theory

a.critica. review of prepa.a.ion design a.d worka.ility mea.urement of concrete materia. for la.gesca.e 3D printing

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Frontiers of Structura. a.d Civil Engineering 2018年第3期12卷 382-400页

作者： Guowei ma Li Wa.G College of a.chitecture a.d Civil Engineering Beijing University of Technology Beijing 100124 China School of Civil Environmental and Mining Engineering The University of Western Australia Crawley WA 6009 Australia School of Mecha.ics a.d Civil engineering China University of Mining & Technology at Beijing Beijing 100083 China

In recent few yea.s, significa.t improvement ha. been made in developing la.gesca.e 3D printers to a.commoda.e the need of industria.-sca.e 3D printing. It is of grea. fea.ibility to construct structura. components a.d buildings by mea.s of 3D concrete printing. The major issues of this innova.ive technique focus on the prepa.a.ion a.d optimiza.ion of concrete materia.s which possess fa.oura.le printa.le properties a. well a. the mea.urement a.d eva.ua.ion methods of their worka.ility. This pa.er firstly introduces three la.gesca.e 3D printing systems tha. ha.e been successfully a.plied in construction industry. It then summarizes the commonly used ra. materia.s in concrete manufa.turing. Critica. fa.tors tha. should be pa.ticula.ly controlled in materia. prepa.a.ion a.e specified. Ea.y-extrusive, ea.y-flowing, well-builda.le, proper setting time a.d low shrinka.e a.e significa.t for concrete mixture to meet the critica. requirements of a.freeform construction process. Therea.ter, mea.uring methods tha. ca. be employed to a.sess the fresh a.d ha.dened properties of concrete a. ea.ly sta.es a.e suggested. Fina.ly, a.few of eva.ua.ion methods a.e presented which may offer certa.n a.sista.ce for optimizing materia. prepa.a.ion. The objective of this work is to review current design methodologies a.d experimenta. mea.urement a.d eva.ua.ion methods for 3D printa.le concrete materia.s a.d promote its responsible use with la.gesca.e 3D printing technology.

关键词： 3D printing concrete materia. printa.le property worka.ility mea.urement construction a.tomation

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一种三维线弹性随机数值均化方法

西安电子科技大学学报 2016年第4期43卷 92-99页

作者：王南马娟张玉林西安电子科技大学机电工程学院陕西西安710071

对小变形下具有随机微观结构非均质材料的数值均化问题进行了研究.当考虑材料微观结构形态、各组分性质的随机性及相关性时,基于多尺度有限元方法和蒙特卡罗法,建立了非均质材料的随机均化模型.求出了不同边界条件下的随机有效量及其数... 详细信息

对小变形下具有随机微观结构非均质材料的数值均化问题进行了研究.当考虑材料微观结构形态、各组分性质的随机性及相关性时,基于多尺度有限元方法和蒙特卡罗法,建立了非均质材料的随机均化模型.求出了不同边界条件下的随机有效量及其数字特征值以及有效量之间所具有的相关性.考察了随机微观结构参数对随机有效量以及表征体积单元中应力分布的影响.结果表明,在分析非均质材料的宏观有效力学性质时,考虑材料微观结构中客观存在的随机性和相关性非常重要.

关键词：均化随机性和相关性三维线弹性有限元法蒙特卡罗法

Synthesis of a.orphous Pd-ba.ed na.oca.a.ysts for efficient a.coholysis of styrene oxide a.d electrochemica. hydrogen evolution

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Na.o Resea.ch 2023年第4期16卷 4650-4655页

作者： Yiya. Ge Jingjie Ge Bia. Hua.g Xixi Wa.g Guiga. Liu Xia.g-Hua. Sha. Lu ma Bo Chen Gua.ghua.Liu Songmo Du a. Zha.g Hongfei Cheng Qingbo Wa.Shiya. Lu Lujia.g Li Qinba. Yun Kuo Yua. Qinxin Luo Zhichua. J.Xu Yonghua.Du Hua.Zha.g Depa.tment of Chemistry City University of Hong KongHong KongChina Hong Kong Bra.ch of Na.iona. Precious Meta.s materia. Engineering Resea.ch Center(NPMM) City University of Hong KongHong KongChina Shenzhen Resea.ch Institute City University of Hong KongShenzhen 518057China Depa.tment of Chemica. a.d Biologica. Engineering HKUST Jockey Club Institute for Advanced Study&Energy InstituteThe Hong Kong University of Science and TechnologyHong KongChina School of materia.s Science a.d Engineering Nanyang Technological UniversitySingapore 639798Singapore Depa.tment of Chemistry University of Science and Technology of ChinaHefei 230026China Na.iona. Synchrotron Light Source II Brookhaven National LaboratoryUptonNew York 11973USA Sta.e Key La.ora.ory of New Cera.ics&Fine Processing School of Materials Science and EngineeringTsinghua UniversityBeijing 100084China

a.orphous na.omateria.s with long-ra.ge disordered structures could possess distinct properties a.d promising a.plica.ions,especia.ly in ca.a.ysis,a. compa.ed with their conventiona. crysta.line *** is impera.ive to a.hieve the controlled prepa.a.ion of a.orphous noble meta.-ba.ed na.omateria.s for the explora.ion of their pha.e-dependent ***,we report a.fa.ile wet-chemica. reduction stra.egy to synthesize va.ious a.orphous multimeta.lic Pd-ba.ed na.omateria.s,including PdRu,PdRh,a.d *** pha.e-dependent ca.a.ytic performances of distinct Pd-ba.ed na.omateria.s towa.ds diverse ca.a.ytic a.plica.ions ha.e been ***,the usa.e of PdRu na.oca.a.ysts with a.orphous a.d crysta.line fa.e-centered cubic(fcc)pha.es ca. efficiently switch the ring-opening route of styrene oxide to obta.n different products with high selectivity through a.coholysis rea.tion a.d hydrogena.ion rea.tion,***,when used a. a. electroca.a.yst for hydrogen evolution rea.tion(HER),the synthesized a.orphous PdRh na.oca.a.yst exhibits low overpotentia. a.d high turnover frequency va.ues,outperforming its crysta.line fcc counterpa.t a.d most of the reported Pd-ba.ed HER electroca.a.ysts.

关键词： a.orphous na.omateria.s Pd-ba.ed na.oca.a.ysts pha.e engineering of na.omateria.s ring-opening rea.tion of styrene oxide electroca.a.ytic hydrogen evolution

Soil physicochemica. a.d microbia. drivers of tempera.ure sensitivity of soil orga.ic matter decomposition under borea. forests

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Pedosphere 2020年第4期30卷 528-534页

作者： Bea.a.KLIMEK marcin CHODa. matgorza.a.Ja.wa.Ha.ed a.a.Ba. maria.NIKLINSKA Institute of Environmenta. Sciences Faculty of BiologyJagiellonian UniversityGronostajowa 7Krakow 30-387(Poland) Depa.tment of ma.a.ement a.d Protection of Environment AGH University of Science and TechnologyMickiewicza 30Krakow 30-059(Poland) Institute of Biology Faculty of Natural Sciences and TechnologyUniversity of OpoleOleska 22Opole 45-052(Poland)

Soil orga.ic matter(SOM)in borea. forests is a. importa.t ca.bon *** a.m of this study wa. to a.sess a.d to detect fa.tors controlling the tempera.ure sensitivity of SOM *** were collected from Scots pine,Norwa. spruce,silver birch,a.d mixed forests(O horizon)in northern Finla.d,a.d their ba.a. respira.ion ra.es a. five different tempera.ures(from 4 to 28℃)were *** Q10 va.ues,showing the respira.ion ra.e cha.ges with a.10℃ increa.e,were ca.cula.ed using a.Ga.ssia. function a.d were ba.ed on tempera.ure-dependent *** soil physicochemica. pa.a.eters were mea.ured,a.d the functiona. diversity of the soil microbia. communities wa. a.sessed using the MicroResp?*** tempera.ure sensitivity of SOM decomposition differed under the studied forest *** forests ha. the highest tempera.ure sensitivity for SOM decomposition a. the low tempera.ure ra.ge(0–12℃).Within this tempera.ure ra.ge,the Q10 va.ues were positively correla.ed with the microbia. functiona. diversity index(H’mic)a.d the soil C-to-P *** suggested tha. the meta.olic a.ilities of the soil microbia. communities a.d the soil nutrient content were importa.t controls of tempera.ure sensitivity in ta.ga.soils.

关键词： CoO2 evolution globa. wa.ming microbia. functiona. diversity MicroResp^TM Q10 meta.olic coefficient

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黑龙江3种野生雌性茴鱼肌肉与卵的营养品质

广东海洋大学学报 2024年第4期44卷 55-62页

作者：韩豪祥韩世成张颖孙文韬马波中国水产科学研究院黑龙江水产研究所农业农村部黑龙江流域渔业资源与环境科学观测实验站150076 上海海洋大学水产与生命学院上海201306

【目的】对比分布于黑龙江流域的黑龙江茴鱼(Thymallus grubii)、下游黑龙江茴鱼(Thymallus tuga.ina.)和贝加尔茴鱼(Thymallus ba.ca.ensis)在性成熟时期的肌肉及卵的营养品质。【方法】采集处于卵巢Ⅳ期的3种茴鱼的肌肉与卵,检测其水... 详细信息

【目的】对比分布于黑龙江流域的黑龙江茴鱼(Thymallus grubii)、下游黑龙江茴鱼(Thymallus tuga.ina.)和贝加尔茴鱼(Thymallus ba.ca.ensis)在性成熟时期的肌肉及卵的营养品质。【方法】采集处于卵巢Ⅳ期的3种茴鱼的肌肉与卵,检测其水分、粗灰分、粗脂肪、粗蛋白质含量以及氨基酸、脂肪酸组成等营养指标并进行评价。【结果】3种茴鱼卵常规营养成分含量均高于肌肉,其中卵水分、卵灰分、卵脂肪与卵蛋白质含量均有种间差异(P a.)/w(Ta.)]最高,分别为38.39%、39.79%;下游黑龙江茴鱼肌肉和黑龙江茴鱼卵的鲜味氨基酸质量分数/氨基酸总质量分数[w(Da.)/w(Ta.)]最高,分别为39.77%、33.44%;黑龙江茴鱼肌肉与下游黑龙江茴鱼卵的必需氨基酸指数(Ea.I)最高,分别为73.41、100.60。3种茴鱼肌肉与卵的第一限制氨基酸均为色氨酸,第二限制氨基酸均为蛋氨酸+胱氨酸。下游黑龙江茴鱼、贝加尔茴鱼的肌肉检出19种脂肪酸,黑龙江茴鱼肌肉仅检出16种脂肪酸,3种卵中均检出16种脂肪酸;其中,肌肉营养成分中下游黑龙江茴鱼的脂肪酸配比更为理想,在卵营养成分中贝加尔茴鱼的脂肪酸配比更为理想。肌肉与卵的常量元素均为高K低Na.,且富含Fe、Zn、Cu、Mg等微量元素,下游黑龙江茴鱼和贝加尔茴鱼的矿物质含量较黑龙江茴鱼略高。【结论】3种性腺发育处于IV期的雌性野生茴鱼肌肉与卵均具有较高的营养价值,其中下游黑龙江茴鱼和贝加尔茴鱼肌肉与卵营养成分组成及配比较黑龙江茴鱼更为合理,因此黑龙江茴鱼以及尚未开展人工养殖的下游黑龙江茴鱼、贝加尔茴鱼具有广阔的养殖前景。

关键词：黑龙江茴鱼下游黑龙江茴鱼贝加尔茴鱼肌肉卵营养品质

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Riorda.阵与Ca.chy多项式

数学的实践与认识 2011年第24期41卷 200-209页

作者：马高娃乌云高娃内蒙古大学数学系内蒙古呼和浩特010021

给出了Ca.chy多项式c_n~α(z)的定义,并导出它的生成函数.再利用Riorda.阵方法得到包含Ca.chy多项式的一些恒等式,获得它与广义调和多项式H_n^((r))(z),广义Stirling多项式P_(n,r)(z)的关系式.

关键词： Riorda.阵 Ca.chy多项式 Stirling数广义调和多项式广义Stirling多项式

a.a.ite-fission-tra.k geochronology a.d its tectonic correla.ion in the Da.iesha. orogen,centra. China

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Science China.Ea.th Sciences 2005年第4期48卷 506-520页

作者： P. Va. Den Ha.te R. a. Donelick J. De Gra.e ma Cha.gqia. P. W. Reiners Geologica. Institute Gent University Krijgslaan281 B9000 Gent BelgiumDonelick Analytical Inc. Viola Idaho83872-2332 USAGeological Institute Gent University Krijgslaan281 B9000 Gent BelgiumFaculty of Earth Sciences China University of Geosciences Wuhan 430074 ChinaDepartment of Geology Washington State University Pullman WA99164-2812 USA

a.T da.a.of gra.itoid a.d meta.orphic sa.ples from the Da.iesha. orogen ha.e a. a.e ra.ge between 96.4 ma.a.d 41.9 ma coupled with confined tra.k lengths of 11.5—14.0 μm, reflecting the cooling time of rocks differentia.ly through the 100℃± isotherm. The Jura.- sic-Eogene sediments from the North Hua.ya.g a.d Hefei ba.in, however, yield their a.T a.es of 128.8—62.0 ma with mea. tra.k lengths of 8.6—11.9 μm, recording a.complica.ed thermal de- velopment of the ba.in. These a.T da.a.structura.ly a.lowing the coupling between the orogen a.d the ba.in a.e to a.grea. extent considered a. the result from the control of NNE-trending regiona. tectonics. It took pla.e a.proximately a. 95—90 ma tha. the orogen developed with a. a.rupt shift from the doming extension to the differentia. tra.stension, which is a.sumed to be rela.ed with the cha.ges of the convergence between the Western Pa.ific a.d Eura.ia.pla.es. The differentia.ly sinistra. strike-slipping from the tra.stension between Ta.lu a.d Sha.g- cheng-macheng fa.lts brought the doming extension of the orogen shrunk sha.ply in La.e Cre- ta.eous. In Eogene, the full-grown tra.stension tha. domina.ed in Ea.t a.ia.wa. ca.sed mainly by a.ra.id decrea.e of the ra.es of the Western Pa.ific convergence, which ca. be therefore re- ga.ded a. a.major mecha.ism crea.ing the zona. a.omalies of 60—40 ma in the orogen. The thermal a.omaly of 70—40 ma zona.ly a.ong the Ta.lu fa.lt cooled more slowly tha. the a.omaly of 60—55 ma zoning a.ong the Sha.gcheng-macheng fa.lt, but the 60—40 ma.a.omaly trending E-W in hinterla.ds of the orogen seems to be relicts of the doming extension a. a.result of inten- sive rebuilding by the tra.stension. In a.dition, the orogen wa. a.so rea.tiva.ed by the fa.-field effect from India.a.ia.collision in Eogene, where major NWW-trending fa.lts pla.ed a. importa.t role in fa.ilita.ing such fa.-field tectonic tra.sferring. In Oligocene to Miocene, the Da.iesha. orogen remained a.few thermal disturba.ces with

关键词： a.T geochronology, tectonic correla.ion, Da.iesha. orogen.