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Comparison of extraction abilities of deep eutectic solvents and aqueous acid solutions for extraction of rare earths and transition metals

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Journal of Rare Earths 2024年第6期42卷 1157-1164,I0006页

作者： Svetlana Drogobuzhskaya Margarita Frolova Andrey Shishov nikita Tsvetov Tananaev Institute of Chemistry-Subdivision of the Federal Research Centre《Kola Science Centre of the Russian Academy of Sciences》 18420926a AcademgorodokApatityRussia Murmansk State Technical University 183010Sportivnaja str.13MurmanskRussia Department of Analytical Chemistry Institute of ChemistrySaint Petersburg State UniversitySpbSU.1990347/9 Universitetskaya embSt.Petersburg Russia

In recent years,deep eutectic solvents have attracted increasing interest as effective extractants for the separation of both organic substances and metals from various ***-based deep eutectic solvents are most often used as extractants for the extraction of *** this work,for the first time,the extraction efficiency of transition metals and rare earth elements(Y,Zr,Nb,La,Ce,Pr,Nd,Sm,Eu,Gd,Tb,Dy,Ho,Er,Tm,Yb,Lu,Hf and Ta)from mining tailings and Na,K,Ca,Mg,Cu,Fe,Mn,Pb,Ba,Ni and Sr from biodiesel samples using acidic deep eutectic solvents and saturated aqueous solutions of the same acids(malonic,malic,tartaric and citric)is *** this,deep eutectic solvents based on acids and their aqueous saturated solutions were prepared and *** prepared mixtures were analyzed by IR spectroscopy to confirm the formation of eutectic *** such as the density and viscosity of the resulting mixtures were also investigated,as this can be of key importance for the efficiency of metal *** extraction of rare earth metals from mining tailings took a long time(up to several days),while the extraction of metals from fuel took no more than 30 *** emission spectral methods were used as an analysis *** is shown that the extraction efficiency with aqueous solutions is better than that with eutectic solvents,which casts doubt on the need for deep eutectic solvents use in this area.

关键词： Deepeutectic solvent Metal separation Elemental analysis Rare earth metals Biodiesel

Pre-trained Mol2Vec Embeddings as a Tool for Predicting Polymer Properties

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Chinese Journal of Polymer Science 2024年第12期42卷 2059-2068,I0014页

作者： Ivan Zlobin nikita Toroptsev Gleb Averochkin Alexander Pavlov Center NTI“Digital Materials Science:New Materials and Substances” Bauman Moscow State Technical University2S1 Baumanskaya St.5/1105005MoscowRussia A.N.Nesmeyanov Institute of Organoelement Compounds of Russian Academy of Sciences Vavilova St.28Bld.1119334MoscowRussia

Machine learning-assisted prediction of polymer properties prior to synthesis has the potential to significantly accelerate the discovery and development of new polymer *** date,several approaches have been implemented to represent the chemical structure in machine learning models,among which Mol2Vec embeddings have attracted considerable attention in the cheminformatics community since their introduction in ***,for small datasets,the use of chemical structure representations typically increases the dimensionality of the input dataset,resulting in a decrease in model ***,the limited diversity of polymer chemical structures hinders the training of reliable embeddings,necessitating complex task-specific architecture *** address these challenges,we examined the efficacy of Mol2Vec pre-trained embeddings in deriving vectorized representations of *** study assesses the impact of incorporating Mol2Vec compound vectors into the input features on the efficacy of a model reliant on the physical properties of 214 *** results will hopefully highlight the potential for improving prediction accuracy in polymer studies by incorporating pre-trained embeddings or promote their utilization when dealing with modestly sized polymer databases.

关键词： Properties prediction High dimensional embeddings Machine learning Mol2Vec

Metasurfaces for next-generation wireless communication systems

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National Science Review 2023年第8期10卷 17-19页

作者： Younes Ra'di nikita Nefedkin Petar Popovski Andrea Alù Department of Electrical Engineering and Computer Science Syracuse University Photonics Initiative Advanced Science Research Center City University of New York Department of Electronic Systems Aalborg University Physics Program Graduate Center City University of New York

The pace of development in the world of 5G communication systems has proven to be much more demanding than previous generations, with 5G-Advanced seemingly around the corner [1]. Extensive research is already underway to structure the next generation of wireless systems(i.e. 6G), which may potentially enable an unprecedented level of human–machine interaction [2].

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An approach to net-centric control automation of technological processes within industrial IoT systems

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Advances in Manufacturing 2017年第4期5卷 388-393页

作者： nikita Voinov Igor Chernorutsky Pavel Drobintsev Vsevolod Kotlyarov Institute of Computer Science and Technology Peter the Great St. Petersburg Polytechnic UniversityPolytechnicheskaya 29 Saint Petersburg Russia 195251

The use of industrial internet networks with net- centric control is the driving trend behind the future material manufacturing of goods and services. The promising future of this approach is provided by these complex net-centric systems functioning with high relia- bility. The problem of intelligent net-centric control and reliable network functioning is fundamental, with the additional requirement that the system should preserve stakeholder security and privacy according to policies. The issue is that such systems are characterized by complex multi-parameter operability modes controlled by various criteria. This study considers an approach to providing reliable management of complicated Internet of things （IoT） systems. This is achieved by solving multi-criteria tasks over many processes of various physical natures. Corresponding methods of hierarchical decomposition of multi-criteria tasks, process levels of multi-criteria opti- mization, specifics of aggregation levels, and the master equation of the optimization process are described.

关键词： Net-centric control Technological process Internet of things (IoT) Reliability Multi-criteria optimization

A rare co-occurrence of spontaneous pneumomediastinum,pneumothorax,and pneumoperitoneum:Macklin effect

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World Journal of Emergency Medicine 2024年第3期15卷 246-248页

作者： Renaldo Pavrey nikita Makwana Nisha Das Centre for Accident and Emergency Medicine Nanavati Max Super Specialty HospitalMumbai 400050India

Spontaneous pneumomediastinum (SPM) is characterized by free air or gas located within the mediastinum that is not associated with any noticeable cause,such as chest trauma,intrathoracic infections,surgery,other organ... 详细信息

关键词： rupture trauma infections

Preparation of stable colloidal suspensions of superdisintegrants via wet stirred media milling

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Particuology 2014年第3期12卷 76-82页

作者： Mohammad A.Azad Afolawemi Afolabi nikita Patel Rajesh Davé Ecevit Bilgili Otto H.York Department of Chemical Biologicaland Pharmaceutical EngineeringNew Jersey Institute of TechnologyNewarkNJUSA

Superdisintegrants are cross-linked polymers that can be used as dispersants for fast release of drug nanoparticles from nanocomposite microparticles during in vitro and in vivo dissolution. Currently avail- able superdisintegrant particles have average sizes of approximately 5-130 μm, which are too big for drug nanocomposite applications. Hence, production of stable superdisintegrant suspensions with less than 5 μm particles is desirable. Here, we explore the preparation of colloidal suspensions of anionic and nonionic superdisintegrants using a wet stirred media mill and assess their physical stability. Sodium starch glycolate （SSG） and crospovidone （CP） were selected as representative anionic and nonionic superdisintegrants, and hydroxypropyl cellulose （HPC） and sodium dodecyl sulfate （SDS） were used as a steric stabilizer and a wetting agent/stabilizer, respectively. Particle sizing, scanning electron microscopy, and zeta potential measurements were used to characterize the suspensions. Colloidal superdisintegrant suspensions were prepared reproducibly. The extensive particle breakage was attributed to the swelling-induced softening in water. SSG suspensions were stable even in the absence of stabilizers, whereas CP suspensions required HPC-SDS for minimizing particle aggregation. These findings were explained by the higher absolute （negative） zeta potential of the suspensions of the anionic superdisintegrant （SSG） as compared with those of the nonionic superdisintegrant （CP）.

关键词： Colloidal suspensions Dispersants Physical stability Superdisintegrants Swelling Wet stirred media milling

Experimental repetitive mild traumatic brain injury induces deficits in trabecular bone microarchitecture and strength in mice

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Bone Research 2017年第4期5卷 357-366页

作者： Chandrasekhar Kesavan nikita M Bajwa Heather Watt Subburaman Mohan Musculoskeletal Disease Center VA Loma Linda Healthcare SystemLama LindaCAUSA Department of Medicine Loma DndaCAUSA Department of Orthopedic Surgery Loma Linda UniversityLoma LindaCAUSA

To evaluate the long-term consequence of repetitive mild traumatic brain injury （mTBI） on bone, mTBI was induced in 10-week-old female C57BL/6J mice using a weight drop model, once per day for 4 consecutive days at different drop heights （0.5, 1 and 1.5 m） and the skeletal phenotype was evaluated at different time points after the impact. In vivo micro-CT （μ-CT） analysis of the tibial metaphysis at 2, 8 and 12 weeks after the impact revealed a 5%-32% reduction in trabecular bone mass. Histomorphometric analyses showed a reduced bone formation rate in the secondary spongiosa ofl.5 m impacted mice at 12 weeks post impact. Apparent modulus （bone strength）, was reduced by 30% （P 〈 0.05） at the proximal tibial metaphysis in the 1.5 m drop height group at 2 and 8 weeks post impact. Ex vivo μ-CT analysis of the fifth lumbar vertebra revealed a significant reduction in trabecular bone mass at 12 weeks of age in all three drop height groups. Serum levels of osteocalcin were decreased by 22%, 15%, and 19% in the 0.5, 1.0 and 1.5 m drop height groups, respectively, at 2 weeks post impact. Serum IGF-I levels were reduced by 18%-32% in mTBI mice compared to control mice at 2 weeks post impact. Serum osteocalcin and IGF-I levels correlated with trabecular BV/TV （r2 = 0.14 and 0.16, P 〈 0.05）. In conclusion, repetitive mTBI exerts significant negative effects on the trabecular bone microarchitecture and bone mechanical properties by influencing osteoblast function via reduced endocrine IGF-I actions.

关键词： IGF TBI Experimental repetitive mild traumatic brain injury induces deficits in trabecular bone microarchitecture and strength in mice

Structural and geochemical features of coal‑bearing sediments and sources of rare element impurities in coals of the Rakovka depression,Primorsky Krai,Russia

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International Journal of Coal Science & Technology 2022年第1期9卷 71-83页

作者： nikita Popov Igor Chekryzhov Irina Tarasenko Sergery Kasatkin Aleksei Kholodov Far East Geological Institute FEB RAS VladivostokRussian Federation

There are known brown coal deposits in Primorsky Krai(Russian Federation),where coals contain rare elements(Ge,U,REE,etc.)up to industrial *** of the known metalliferous coals is the Rakovka coal-bearing depression,located on the southern edge of the Khanka(Prikhankaiskaya)Lowland,with an area of about 70 ***-metal granites with a developed weathering crust are spread in its basement and *** structural conditions forming the depression were studied using measurements of orientations of structural elements(layering,contacts,veins,and dikes)with regard to kinematic conditions of *** coal and host rocks were sampled in sections in the cross strike of the coal *** and dikes cutting them were sampled by separate rock chip *** chemical composition and element content were determined for all *** was found that the adjacent rocks played a major role in the formation of the Rakovka rare-metal-coal *** rare-elements enrichment is not associated with active tectonics,faults,and hydrothermal sources,as was previously ***,it was caused by the hydrogenic and clastogenic removal of these metals from the weathering crust of granites of the depression's flanks and argillated basite dikes cutting the *** hydrogenic nature of the anomalous accumulation of U in sorbed form on organic matter of coals is confirmed by the predominant enrichment of low-ash *** earth elements entered coal seams both in mineral and dissolved forms.A model of REE and uranium input into the coal-bearing sediments of the Rakovka depression was proposed.

关键词： REE Rare metal-coal deposit Accumulation pattern Tectonics

Colorimetric Sensor for Detection of Tabun Mimic Diethyl Cyanophosphonate

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Journal of Analysis and Testing 2024年第3期8卷 374-384页

作者： Madhu Bala Dheeraj Pandey nikita Patel Sheetal Yadav Abha Sharma Department of Medicinal Chemistry National Institute of Pharmaceutical Education and ResearchRaebareliTransit CampusLucknow226002UPIndia

Herein,a colorimetric chemosensor(probe 7)was designed and synthesized for sensing diethyl cyanophosphonate(DCNP),a Tabun nerve agent *** sensitive,selective,fast response and photostable probe 7 in dimethylsulfoxide(DMSO)responded to DCNP at low concentrations with visual naked eye color change from pink to pale yellow and displayed unresponsive behaviour against various interferences except for copper ions,which can be differentiated by adding ethylene diamine where the yellow color persisted in the case of DCNP but turned to pink in the case of copper ***,the yellow aqueous solution of probe 7 at pH 10 and 12 turned colorless against the response of *** limit of detection(LOD)of probe 7 was found to be 50 nmol/L in an aqueous basic solution at pH 10 for the detection of *** formation of the cyclized product was elucidated by 1H and 31P NMR nuclear magnetic resonance(1H NMR,31P NMR),Fourier transform infrared spectroscopy(FTIR),and high-resolution mass spectrometry(HRMS)*** filter paper and silica plate loaded with probe 7 were fabricated for real-time and on-site detection of DCNP.

关键词： Colorimetric Fluorescence Tabun mimic Chemosensor