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The exoskeleton of vertebrates: the geometric regularities of the formation of armor relief in early jawless vertebrates (Agnatha, Vertebrata) 脊椎动物的外骨骼:早期无颌脊椎动物甲状浮雕形成的几何规律(Agnatha, Vertebrata)
Доклады Академии наук Pub Date : 2019-11-10 DOI: 10.31857/s0869-5652489199-102
O. Afanassieva, О Б Афанасьева
{"title":"The exoskeleton of vertebrates: the geometric regularities of the formation of armor relief in early jawless vertebrates (Agnatha, Vertebrata)","authors":"O. Afanassieva, О Б Афанасьева","doi":"10.31857/s0869-5652489199-102","DOIUrl":"https://doi.org/10.31857/s0869-5652489199-102","url":null,"abstract":"Based on the analysis of information on the structure of the hard cover of different taxons of osteostracan jawless vertebrates (Osteostraci, Agnatha), the geometric regularities of the formation of possible variants of armor relief during the exoskeletal morphogenesis of vertebrates are revealed. A circular model of the сonstruction of superficial relief is proposed. It is shown that the early vertebrates have already possessed the mechanism providing realization of complete set of variants of the formation of exoskeletal sculpture of different types.","PeriodicalId":24047,"journal":{"name":"Доклады Академии наук","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-11-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88271100","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
The influence of sodium and potassium doping effect on phase formation in calcium sulphate synthesis 硫酸钙合成中钠、钾掺杂对相形成的影响
Доклады Академии наук Pub Date : 2019-11-10 DOI: 10.31857/s0869-5652489149-52
D. Khayrutdinova, V. Smirnov, O. Antonova, M. Goldberg, S. Smirnov, T. Obolkina, S. Barinov
{"title":"The influence of sodium and potassium doping effect on phase formation in calcium sulphate synthesis","authors":"D. Khayrutdinova, V. Smirnov, O. Antonova, M. Goldberg, S. Smirnov, T. Obolkina, S. Barinov","doi":"10.31857/s0869-5652489149-52","DOIUrl":"https://doi.org/10.31857/s0869-5652489149-52","url":null,"abstract":"Calcium sulphate-based materials were synthesized and investigated, in which Ca2+ cations were substituted for Na+ or K+ cations in an amount of 5, 10 and 20 mol.%. With the introduction of Na+, materials with the structure semi-aqueous and two-water calcium sulfate were obtained, with the introduction of potassium, a mixture of calcium sulfates with different content of chemically bound water and sulfates were obtained, in which potassium cations are forming compounds with different Ca/K ratio. Doping of calcium sulphate with potassium and sodium cations led to an increase in the solubility of materials: for sodium-containing ones by 1,2 times, for potassium-containing ones by 3-4 times. The developed materials are promising for use in medicine for filling bone tissue defects, and can also be used as a cement matrix for targeted drug delivery.","PeriodicalId":24047,"journal":{"name":"Доклады Академии наук","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-11-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80202435","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 1
The first AMS radiocarbon dates of organic matter microinclusions in the ice wedge of the upper part of the Batagay yedoma megaslump, Yakutia 雅库特Batagay yedoma巨型块体上部冰楔有机质微包裹体的首个AMS放射性碳测年
Доклады Академии наук Pub Date : 2019-11-10 DOI: 10.31857/s0869-5652489189-92
Y. Vasil'chuk, J. Vasil’chuk
{"title":"The first AMS radiocarbon dates of organic matter microinclusions in the ice wedge of the upper part of the Batagay yedoma megaslump, Yakutia","authors":"Y. Vasil'chuk, J. Vasil’chuk","doi":"10.31857/s0869-5652489189-92","DOIUrl":"https://doi.org/10.31857/s0869-5652489189-92","url":null,"abstract":"Microinclusions of organic matter were dated using acceleration mass spectrometry in seven samples from the upper part of the thick Pleistocene syngenetic ice wedges uncovered in the outcrop of the Batagay yedoma located in northern Yakutia along the upper Yana River (67,58 N, 134,77 E). The dated fragment of ice wedge was formed within 22 760-20 010 radiocarbon years BP (or 27 100-33 800 cal BP). Using detailed isotope data, the January average air temperature in the Late Pleistocene (25-30 cal kyr BP) was calculated for the Batagay section along with a series of reference sections in northwestern Yakutia. It was shown that the minimum January average air temperature (-51 C) was characteristic at that time for the area of the Batagaika crater, with values 4-5 higher in areas 500-600 km further north. This effect was caused by the occurrence of the Yakutian anticyclone in winter during the Late Pleistocene, which was just as pronounced as that at the present time.","PeriodicalId":24047,"journal":{"name":"Доклады Академии наук","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-11-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91039593","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Optimal control and maximum principle in (B)-spaces. Examples for partial differential equations in (H)-spaces and ordinary differential equations in Rn (B)-空间的最优控制和最大原理。(H)-空间中的偏微分方程和Rn中的常微分方程的例子
Доклады Академии наук Pub Date : 2019-11-10 DOI: 10.31857/s0869-5652489111-16
A. I. Prilepko
{"title":"Optimal control and maximum principle in (B)-spaces. \u0000Examples for partial differential equations in (H)-spaces and ordinary differential equations in Rn","authors":"A. I. Prilepko","doi":"10.31857/s0869-5652489111-16","DOIUrl":"https://doi.org/10.31857/s0869-5652489111-16","url":null,"abstract":"Observation and control problems in Banach (B)-spaces are investigated. On the basis of the BUME method and the monotone mapping method, a criterion of controllability and optimal controllability is formulated. The inverse controllability problem is introduced and an abstract maximum principle is formulated in (B)-spaces. For PDE in Hilbert (H)-spaces and for ODE in Rn, the integral maximum principle is proved and the optimality system is written out.","PeriodicalId":24047,"journal":{"name":"Доклады Академии наук","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-11-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82426758","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Formation of drop-shaped inclusions based on Pt, Pd, Au, Ag, Bi, Sb, Te, As during crystallization of the intermediate solid solution in the Cu-Fe-Ni-S system Cu-Fe-Ni-S体系中间固溶体结晶过程中Pt、Pd、Au、Ag、Bi、Sb、Te、As类水滴状夹杂物的形成
Доклады Академии наук Pub Date : 2019-11-10 DOI: 10.31857/s0869-5652489170-74
E. Sinyakova, V. Kosyakov, N. Goryachev
{"title":"Formation of drop-shaped inclusions based on Pt, Pd, Au, Ag, Bi, Sb, Te, As during crystallization of the intermediate solid solution in the Cu-Fe-Ni-S system","authors":"E. Sinyakova, V. Kosyakov, N. Goryachev","doi":"10.31857/s0869-5652489170-74","DOIUrl":"https://doi.org/10.31857/s0869-5652489170-74","url":null,"abstract":"The phase and chemical composition of drop-shaped inclusions in directionally crystallized intermediate solid solution was studied. The initial melt contained (in mol.%): Fe 31,79; Cu 15,94; Ni 1,70; S 50,20; Sn 0,05; As 0,04; Pt, Pd, Rh, Ru, Ag, Au, Se, Te, Bi, Sb 0,03. Experimental data indicate the simultaneous crystallization of two types of liquids upon cooling of the initial sulfide melt. One of them is formed in the subsystem (Pd, Au, Ag)-(Bi, Sb, Te), and the second - in the subsystem Cu-(S, Bi, Sb, Te). When these liquids solidified, inclusions formed, which we divided into four classes. Class I has a eutectic-like structure with a matrix of Pd(Bi,Sb)xTe1-x solid solution and Au crystallites with Ag, Cu, and Pd impurities. Class II is formed from sulfosalts with inclusions of Bi and Au. Class III includes inclusions of sperrylite Pt(As,S)2. Class IV forms compound inclusions from fragments of classes I-III. The experiment described in the work showed a more complex behavior of noble metals and metalloid impurities during the crystallization of complex sulfide-metalloid melts compared with the previously described data of isothermal experiments.","PeriodicalId":24047,"journal":{"name":"Доклады Академии наук","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-11-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82428834","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 1
Mono- and di(dechloromethylthioylation) of the dichloromethylarenes by S-methyldiethylthiophosphinate s -甲基二乙基硫代膦酸盐对二氯甲基芳烃的单和二(脱氯甲基硫代)化反应
Доклады Академии наук Pub Date : 2019-11-10 DOI: 10.31857/s0869-5652489140-43
M. B. Gazizov, G. D. Valieva, S. Ivanova, R. Khairullin, Yu. S. Kirillina, I. Antipin
{"title":"Mono- and di(dechloromethylthioylation) of the dichloromethylarenes by S-methyldiethylthiophosphinate","authors":"M. B. Gazizov, G. D. Valieva, S. Ivanova, R. Khairullin, Yu. S. Kirillina, I. Antipin","doi":"10.31857/s0869-5652489140-43","DOIUrl":"https://doi.org/10.31857/s0869-5652489140-43","url":null,"abstract":"Proceeding from the electronic structure of the S‑alkyl esters of P(IV) acids the key rout - attack of the thiol sulfur (P-SMe) on the methyne carbon, of the new reaction of the dichloromethylarenes with S‑methyldiethylthiophosphinate was predicted and experimentally confirmed. The processes of the mono- and di(dechloromethylthioylation) on dichloromethyl group are realized. New approach to the synthesis of the arenecarbaldehyde dimethyl dithioacetals was developed without using of gaseous high toxic methyl mercaptan.","PeriodicalId":24047,"journal":{"name":"Доклады Академии наук","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-11-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76493244","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Simulation of heterogeneous plasma microfield 非均匀等离子体微场模拟
Доклады Академии наук Pub Date : 2019-11-10 DOI: 10.31857/s0869-5652489122-26
A. Belov, Алексей Александрович Белов, N. N. Kalitkin, Н.Н. Калиткин
{"title":"Simulation of heterogeneous plasma microfield","authors":"A. Belov, Алексей Александрович Белов, N. N. Kalitkin, Н.Н. Калиткин","doi":"10.31857/s0869-5652489122-26","DOIUrl":"https://doi.org/10.31857/s0869-5652489122-26","url":null,"abstract":"Optical properties of plasma are determined by presence of fluctuating micro-scopic electric field. In the present work, we construct a simple ab initio model of plasma microfield accounting for its heterogeneity up to octupole term for the first time. Comparison with experiments shows that only this model describes the observed number of spectral lines.","PeriodicalId":24047,"journal":{"name":"Доклады Академии наук","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-11-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81275655","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
First results of dating detrital zircons from the late precambrian quartzite-schist sequences of Chu block (Southern Kazakhstan) 哈萨克斯坦南部楚地块晚前寒武纪石英岩-片岩层序碎屑锆石定年初步结果
Доклады Академии наук Pub Date : 2019-11-10 DOI: 10.31857/s0869-5652489157-61
N. A. Kanygina, A. Tretyakov, K. .. Degtyarev, K. Pang, K. L. Van, H. Lee, J. Plotkina
{"title":"First results of dating detrital zircons from the late precambrian quartzite-schist sequences of Chu block (Southern Kazakhstan)","authors":"N. A. Kanygina, A. Tretyakov, K. .. Degtyarev, K. Pang, K. L. Van, H. Lee, J. Plotkina","doi":"10.31857/s0869-5652489157-61","DOIUrl":"https://doi.org/10.31857/s0869-5652489157-61","url":null,"abstract":"U-Pb geochronological studies of detrital zircons from quartzite-schist sequences of the Akbastau Formations of the Chu block (northwest of the Chu-Kendyktas terrane, Southern Kazakhstan) have been provided. The concordant ages of detrital zircons are predominantly within the intervals of 1672-2115 Ma with peaks at 1697, 1780, 1857 and 2066 Ma. Individual zircon grains display ages of 2291-2332 Ma with peaks at 2303 and 2322 Ma. Neoarchean ages 2608-2747 with peak at 2681 Ma characterize another significant zircon population. The lower limit of deposition for the Akbastau Formations of the Chu block, corresponding to the youngest statistically significant zircon population, is estimated at 1,7 billion years.","PeriodicalId":24047,"journal":{"name":"Доклады Академии наук","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-11-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90829699","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Fabrication of a composite based on aluminum oxide nanofibers and nanodiamonds to construct phenol detection systems 基于氧化铝纳米纤维和纳米金刚石复合材料构建苯酚检测系统的制备
Доклады Академии наук Pub Date : 2019-11-10 DOI: 10.31857/s0869-5652489144-48
N. Ronzhin, Н О Ронжин, E. Posokhina, Е Д Посохина, E. Mikhlina, Е В Михлина, M. Simunin, М М Симунин, I. Nemtsev, Иван В. Немцев, I. Ryzhkov, Илья И. Рыжков, V. Bondar, Владимир Станиславович Бондарь
{"title":"Fabrication of a composite based on aluminum oxide nanofibers and nanodiamonds to construct phenol detection systems","authors":"N. Ronzhin, Н О Ронжин, E. Posokhina, Е Д Посохина, E. Mikhlina, Е В Михлина, M. Simunin, М М Симунин, I. Nemtsev, Иван В. Немцев, I. Ryzhkov, Илья И. Рыжков, V. Bondar, Владимир Станиславович Бондарь","doi":"10.31857/s0869-5652489144-48","DOIUrl":"https://doi.org/10.31857/s0869-5652489144-48","url":null,"abstract":"A composite based on aluminum oxide nanofibers (AONF) and modified nanodiamonds (MND) synthesized by explosion technique was made by mixing aqueous suspensions of components at a 5:1 weight ratio and incubating the mixture for 15 minutes at 32 C. It is assumed that the formation of a composite is provided by the difference in the zeta-potentials of the components - negative for MND and positive for AONF. Vacuum filtration of the mixture through a fluoroplastic filter (pore diameter of 0.6 m) formed discs with a diameter of 40 mm with subsequent heat treatment at 300 C to impart structural stability to the composite. Using scanning electron microscopy (SEM), it was revealed that the resulting composite has a network structure in which the MND particles are distributed over the AONF surface. It was established that MND incorporated into the composite catalyze the azo coupling reaction (phenol - 4-aminoantipyrine - H2O2) with the formation of a colored product (quinoneimine). The applicability of the composite for the multiple detection of phenol in aqueous samples is demonstrated.","PeriodicalId":24047,"journal":{"name":"Доклады Академии наук","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-11-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91201765","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Unique role of pore water in lateritic bauxite formation, Republic of Guinea 孔隙水在几内亚红土铝土矿地层中的独特作用
Доклады Академии наук Pub Date : 2019-11-10 DOI: 10.31857/s0869-5652489165-69
M. Makarova, V. Mamedov, Y. V. Alekhin, E. Shipilova
{"title":"Unique role of pore water in lateritic bauxite formation, Republic of Guinea","authors":"M. Makarova, V. Mamedov, Y. V. Alekhin, E. Shipilova","doi":"10.31857/s0869-5652489165-69","DOIUrl":"https://doi.org/10.31857/s0869-5652489165-69","url":null,"abstract":"Results of the hydrogeochemical study of bauxite-bearing lateritic mantles of the Futa Djallon-Mandingo Province, West Africa, have allowed us to first characterize the pore water of vadose and infiltration hydrogeological zone. Abundances of major components (aluminum and iron) of the water are shown to be few orders higher than are those typical of the other waters of lateritic mantles. The pore water is proved to be a major factor of matter redistribution over any bauxite-bearing lateritic profile.","PeriodicalId":24047,"journal":{"name":"Доклады Академии наук","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-11-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79224834","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 1
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