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Blasting practices in a quarry with karstic cavities

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Journal of University of Science and Technology Beijing 2002年第6期9卷 406-411页

作者： g.SevketKoruc BirolElevli 等 DogantasAs.58030Sivas Turkey MiningEngineeringDepartment CumburiyetUniversity58140Turkey

The blasting practices in a limestone quarry with karstic cavities have beenpresented. The existence of karstic cavities in the quarry has reduced blasting efficiencysignificantly. In order to improve blasting efficiency different blasting strategies (loading holeswith ANfO in plastic bag, recording cavity location along the holes and charging the holes accordingto this information, and modifying blasting pattern according to karstic cavities) had beenimplemented and the results were evaluated on per ton cost basis. It was concluded that efficientblasting in such aquarries requires determining the size and shape of karstic cavities and based onthis information, to modify the blast pattern and charge the holes. The suggested method is torecord the cavity along the drill hole and to generate 3D model of cavities. By doing this, theproduction cost in the limestone quarry has decreased from 0.407 dollars/t to 0.354 dollars/t.

关键词： blasting fragmentation karstic cavities limestone quarry

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尿核苷和腺核苷的2＇位烯丙基化反应

有机化学 1989年第5期9卷 445-448页

作者：张海翔 f.guibé g.Balavoine Institut Institut de Chimie Moléculaire d'Orsay Laboratoire de Chimie Organique des Eléments de Transition

在核苷酸合成中,核糖2＇位羟基的保护是不易的,主要原因是难以区别2＇位和3＇位的两个羟基。Markiewicz曾提出利用试剂1,3-二氯-1,1,3,3-四异丙基二硅氧烷（简写为TIPDSiCl2）作为暂时保护基团的好方法。但是,这种方法不适应醚形式的2... 详细信息

在核苷酸合成中,核糖2＇位羟基的保护是不易的,主要原因是难以区别2＇位和3＇位的两个羟基。Markiewicz曾提出利用试剂1,3-二氯-1,1,3,3-四异丙基二硅氧烷（简写为TIPDSiCl2）作为暂时保护基团的好方法。但是,这种方法不适应醚形式的2＇位羟基的保护。

关键词：烯丙基钯尿嘧啶核苷腺嘌呤核苷

Strengthening mechanisms in magnesium alloys containing ternary Ⅰ,W and LPSO phases

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Journal of Materials Science & Technology 2018年第7期34卷 1110-1118页

作者： N.Tahreen D.f. zhang f.S. Pan X.Q. Jiang D.Y. Li D.L. Chen Department of Mechanical and Industrial Engineering Ryerson University Toronto Ontario MSB 2K3 Canada College of Materials Science and Engineering Chongqing University Chongqing 400045 China National Engineering Research Center for Magnesium Alloys Chongqing University Chongqing 400044 China Advanced Materials Research Center ChongqingAcademy of Science and Technology Chongqing 401123 China faculty of Materials and Energy Southwest University Chongqing 400715 China Department of Chemical and Materials Engineering University of Alberta Alberta T6G 11-19 Canada

This study was aimed at identifying underlying strengthening mechanisms and predicting the yield strength of as-extruded Mg-zn-Y alloys with varying amounts of yttrium （Y） element. The addition of Y resulted in the formation of ternary 1 （Mg3Yzn6）, W （Mg3Y2zn3） and LPSO （Mg12Yzn） phases which subse- quently reinforced alloys zM31 ＋ 0.3Y, zM31 ＋ 3.2Y and zM31 ＋ 6Y, where the value denoted the amount of Y element （in wt%）. Yield strength of the alloys was determined via uniaxial compression testing, and grain size and second-phase particles were characterized using OM and SEM. In-situ high-temperature XRD was performed to determine the coefficient of thermal expansion （CTE）, which was derived to be 1.38 x 10^-5 K^-1 and 2.35 x 10^-5 K^-1 for W and LPSO phases, respectively. The individual strengthening effects in each material were quantified for the first time, including grain refinement, Orowan looping, thermal mismatch, dislocation density, load-bearing, and particle shearing contributions. grain refinement was one of the major strengthening mechanisms and it was present in all the alloys studied, irrespective of the second-phase particles. Orowan looping and crE mismatch were the predominant strengthening mechanisms in the zM31＋0.3Y and zM31 ＋ 3.2Y alloys containing I and W phases, respectively, while load-bearing and second-phase shearing were the salient mechanisms contributing largely to the superior yield strength of the LPSO-reinforced zM31 ＋ 6Y alloy.2017 Published by Elsevier Ltd on behalf of The editorial office of Journal of Materials Science ＆ Technology.

关键词： Magnesium alloy I-phase W-phase LPSO phase Strengthening mechanism

Hydrogenated silicon as the lithium-ion battery anode for improving initial Columbic efficiency and cyclability

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Hydrogenated silicon as the lithium-ion battery anode for im...

A possibility of saving an endangered endemic of the Lake Baikal shore, <i>Hedysarum zundukii</i>Peschkova (<i>fabaceae</i>Lindl.) using clonal micropropagation

中国化学会第三届中国能源材料化学研讨会

作者： Y.z.Cao f.zhang Q.A Huang X.D.Huang Key Laboratory of MEMS of the Ministry of Education Southeast University

Silicon has attracted much attention as the lithium-ion battery(LIB) anode due to its ultrahigh theoretical specific capacity(4200 mAh g) and abundance in the ***,severe stress would be induced by the drastic volume c...

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Natural Science 2013年第12期5卷 1289-1297页

作者： Kim z. gamburg Siberian Institute of Plant Physiology and Biochemistry Siberian Branch of the Russian Academy of Sciences 664033 Irkutsk P. O. box 317 Russia

Hedysarum zundukii Peschkova is one of the fabaceae endemics of the flora of the Lake Baikal west shore. Because of its very poor renewal by seed production and seedling appearance biotechnological method, clonal micropropagation has been elaborated in order to improve its chances of conservation. A protocol for clonal micropropagation, including introduction, propagation, rooting, acclimatization, field cultivation and prolonged cold storage has been elaborated. Half-dose MS salts, benzylaminopurine 1 mg/dm3 and 2% sucrose were optimal components of the medium for clonal micropropagation. Sucrose was the superior carbon source by comparison with glucose and maltose. It was found that some agar brands were better for propagation, whereas other ones were better for rooting. Transplants produced from acclimatized plantlets vegetated successfully in field conditions, but did not survived in Irkutsk after wintering. However, the same transplants planted into their natural population survived successfully. Micropropagated plantlets retained their ability for propagation in vitro after 10 -12 months of cold storage at 4℃ with illumination. It was concluded that clonal micropropagation may be used as an additional means for conservation of H. zundukii.

关键词： Agar Brands Carbon Sources Clonal Micropropagation Cold Storage Conservation of Rare Plant Species Hedysarum zundukii Peschkova

The protein-protein interaction landscape of transcription factors during gynoecium development in Arabidopsis

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Molecular Plant 2023年第1期16卷 260-278页

作者： Humberto Herrera-Ubaldo Sergio E.Campos Pablo López-gómez Valentín Luna-garcía Víctor M.zúñiga-Mayo gerardo E.Armas-Caballero Karla L.gonzález-Aguilera Alexander DeLuna Nayelli Marsch-Martínez Carlos Espinosa-Soto Stefan de folter Unidad de genómica Avanzada(UgA-LANgEBIO) Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional(CINVESTAV-IPN)IrapuatoGuanajuato 36824México Departamento de Biotecnología y Bioquímica Unidad IrapuatoCINVESTAV-IPNIrapuatoGuanajuato 36824México Instituto de física Universidad de San Luis PotosíSan Luis PotosíSLP 78290México Present address:Department of Plant Sciences University of CambridgeCambridgeUK Present address:Department of Molecular and Cellular Biology University of California DavisDavisCAUSA Present address:CONACYT Instituto de FitosanidadColegio de PostgraduadosCampus MontecilloTexcocoMéxico

flowers are composed of organs whose identity is defined by the combinatorial activity of transcription factors(Tfs).The interactions between MADS-box Tfs and protein complex formation have been schematized in the floral quartet model of flower *** gynoecium is the flower’s female reproductive part,crucial for fruit and seed production and,hence,for reproductive *** the establishment of carpel identity,many tissues arise to form a mature *** have been described as regulators of gynoecium development,and some interactions and complexes have been ***,broad knowledge about the interactions among these Tfs and their participation during development remains *** this study,we used a systems biology approach to understand the formation of a complex reproductive unit—as the gynoecium—by mapping binary interactions between well-characterized *** analyzed almost 4500 combinations and detected more than 250 protein-protein interactions(PPIs),resulting in a process-specific interaction *** analyses suggest hidden functions and novel roles for many *** addition,we observed a close relationship between Tfs involved in auxin and cytokinin-signaling pathways and other ***,we analyzed the network by combining PPI data,expression,and genetic data,which helped us to dissect it into several dynamic spatio-temporal subnetworks related to gynoecium development ***,we generated an extended PPI network that predicts new players in gynoecium *** together,all these results serve as a valuable resource for the plant community.

关键词： interactome networks transcription factors gynoecium development

“Mexico Knows That There’s a growing Market in China”——Interview with Mexican Ambassador to China José Luis Bernal

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China Today 2017年第8期66卷 46-48页

作者： MICHAEL záRATE

IN february of this year,the new Mexican Ambassador to China,***éLuis Bernal,said before the Mexican Senate that his country was facing unprecedented challenges at the international level that demanded a change to the current paradigm of its relations with the outside *** changes in the United States have sparked debate,with many people insisting that Mexico

关键词：墨西哥中国市场 dose 经济关系参议院多元化

Characteristic of Species Composition of fungi Involved in the formation of Mycobiota of Honey Bees in Azerbaijan

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Advances in Bioscience and Biotechnology 2019年第9期10卷 282-287页

作者： Aysel f.Isayeva guler M.Seyidova Sahla A.Abdullayeva Matanat S.Novruzova Panah z.Muradov Institute of Microbiology of the NAS of Azerbaijan BakuAzerbaijan Azerbaijan Medical University BakuAzerbaijan Azerbaijan State Pedagogical University BakuAzerbaijan

The purpose of the presented work was dedicated to identifying the species composition of the mycobiota of honey bees in Azerbaijan condition. from the samples taken from bees, materials became clear that in the formation of mycobiota those materials (from bees, from where they live and their products) in generally participate 52 species of fungi. Among the recorded fungi, species take part such as Alternaria alternata (fr.) Keissl., Aspergillus flavus Link, Candida albicans (C.P. Robin) Berkhout, Cladosporium herbarum (Pers.) Link, Penicillium cuclopium Westling, P. granulatum Bainier and etc. which carry features conditionally pathogenicity, toxicity, allergens and danger to biological productivity of bees and as well as to pollution of their products. It is known for a long time to scientists that these species are dangerous for human health. for this reason, preparation of normative documents that reflect the principles of microbiological safety of bee products is a necessary task.

关键词： Honey Bees Mycobiota Toxigenes Askosferoz Aspergillosis

“Bolivia ve en China a un socio fundamental”

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今日中国（西文版） 2022年第1期 35-37页

作者： MICHAEL zÁRATE 不详

Entrevista a Mauricio Belmonte,encargado de negocios a.i,de la Embajada de Bolivia en *** China y Bolivia hay una distancia de 18.000 kilómetros,recuerda Mauricio *** embargo,en este diálogo con China Hoy,el encargado de negocios *** la Embajada de Bolivia pone énfasis en los avances alcanzados por ambos países a la liora de reducir otras distancias.

关键词： fundamental China. vista