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Petroleum Science 2020年第3期17卷 811-821页

作者： Daniel V.Dixon stanislav R.Stoyanov Yuming Xu Hongbo Zeng Joao B.P.Soares Department of Chemical and Materials Engineering University of Alberta9211-116 Street NW.EdmontonAB T6G 1H9Canada CanmetENERGY Devon.Natural Resources Canada 1 Oil Patch DriveDevonAB T9G 1A8Canada

Western Canada’s oil sands hold the third-largest hydrocarbon deposits in the ***,a very heavy petroleum,is currently recovered by surface mining with warm water or in *** processes that use organic solvents are being developed to reduce water usage and tailings *** solvent-based methods can effectively extract bitumen,removal of residual fine solids from diluted bitumen product(DBP)to meet the pipeline transport requirement of<0.5 wt%solids and water in DBP remains a major *** propose a novel area of application of polymer flocculants for fine solids removal from *** principle,polymer flocculants can be applied to help remove these residual solids in conjunction with physical separation processes to increase process effectiveness and energy *** polymers are selected and screened for flocculation behavior using kaolinite suspended in DBP and toluene,as a model *** beam reflectance measurements and force tensiometer techniques are used to determine flocculation and sedimentation in *** observed flocculation and sedimentation rate enhancements indicate that the polymers tested have only minor effects,providing opportunities for advanced polymer *** findings exemplify the challenges in identifying polymers that may be effective as flocculants in heavy petroleum media.

关键词： Non-aqueous extraction Diluted bitumen Oil-soluble polymer flocculants Sedimentation in dark and opaque media Focused beam reflectance measurements

Small intestinal bacterial overgrowth syndrome

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World Journal of Gastroenterology 2010年第24期16卷 2978-2990页

作者： Jan Bures Jiri Cyrany Darina Kohoutova Miroslav Frstl stanislav Rejchrt Jaroslav Kvetina Viktor Vorisek Marcela Kopacova 2nd Department of Medicine Charles University in Praha Faculty of Medicine at Hradec Kralove University Teaching Hospital Institute of Clinical Microbiology Charles University in Praha Faculty of Medicine at Hradec Kralove University Teaching Hospital Institute of Experimental Biopharmaceutics Joint Research Centre of Czech Academy of Sciences and PRO.MED.CS Praha a.s. Institute of Clinical Biochemistry and Diagnostics Charles University in Praha Faculty of Medicine at Hradec Kralove University Teaching Hospital

Human intestinal microbiota create a complex polymi-crobial ecology. This is characterised by its high population density, wide diversity and complexity of interaction. Any dysbalance of this complex intestinal microbiome, both qualitative and quantitative, might have serious health consequence for a macro-organism, including small intestinal bacterial overgrowth syndrome (SIBO).SIBO is defined as an increase in the number and/or alteration in the type of bacteria in the upper gastro-intestinal tract. There are several endogenous defence mechanisms for preventing bacterial overgrowth: gastric acid secretion, intestinal motility, intact ileo-caecal valve, immunoglobulins within intestinal secretion and bacte-riostatic properties of pancreatic and biliary secretion. Aetiology of SIBO is usually complex, associated with disorders of protective antibacterial mechanisms (e.g. achlorhydria, pancreatic exocrine insuff iciency, immuno-deficiency syndromes), anatomical abnormalities (e.g. small intestinal obstruction, diverticula, f istulae, surgical blind loop, previous ileo-caecal resections) and/or motility disorders (e.g. scleroderma, autonomic neuropathy in diabetes mellitus, post-radiation enteropathy, small intestinal pseudo-obstruction). In some patients more than one factor may be involved. Symptoms related to SIBO are bloating, diarrhoea, malabsorption, weight loss and malnutrition. The gold standard for diagnosing SIBO is still microbial investigation of jejunal aspirates. Noninvasive hydrogen and methane breath tests are most commonly used for the diagnosis of SIBO using glucose or lactulose. Therapy for SIBO must be com-plex, addressing all causes, symptoms and complica-tions, and fully individualised. It should include treatment of the underlying disease, nutritional support and cyclical gastro-intestinal selective antibiotics. Prognosis is usually serious, determined mostly by the underlying disease that led to SIBO.

关键词： Bacterial overgrowth Breath test Hydrogen Methane Small intestine

Sinterability of nanopowders of terbia solid solutions with scandia,yttria,and lutetia

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Journal of Advanced Ceramics 2018年第4期7卷 362-369页

作者： stanislav S.BALABANOV Dmitry А.PERMIN Elena Ye.ROSTOKINA Sergey V.EGOROV ANDrey A.SOROKIN G.G.Devyatykh Institute of Chemistry of High-Purity Substances RAS Federal Research Center the Institute of Applied Physics RAS

The synthesis of nanopowders of terbia compounds with scandia, yttria, and lutetia was carried out using a self-propagating high-temperature synthesis method involving a mixture of nitrates of metals and glycine as a precursor. The nanopowder phase transformations were investigated using X-ray diffraction analysis. It was found that lutetia has a negligible effect on the phase formation in terbia. On the other hand, yttrium and scandium ions significantly suppressed crystallization. The densification kinetics of nanopowders of the Tb_2O_3 compounds and the microstructure of ceramics after microwave sintering were studied using dilatometry and scanning electron microscopy. The introduction of scandia, yttria, or lutetia contributed to the intensification of the densification of the terbia ceramics when heated in a microwave field. Near full-density materials of terbia solid solutions with lutetia and yttria were obtained at about 1600–1640 ℃. The ceramics of scandia–terbia compounds contained the second phase, which causes light scattering.

关键词： terbia microwave sintering X-ray analysis ceramics

The Problem on Stationary States in Self Gravitational Field

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Journal of Modern Physics 2016年第10期7卷 1045-1048页

作者： stanislav Fisenko “Rusthermosinthes” JSC Moscow Russia

To follow is the problem on stationary states of an electron in its own gravitational field where the boundary conditions earlier described in [1] are made specific. The simplest approximation provides an assessment of the energy spectrum of stationary states only. Nevertheless, this is enough to confirm the existence of such stationary states and to further elaborate a detailed solution of the problem on stationary states including determination of all the quantum numbers’ spectra and corresponding wave functions. No other matters are discussed here. The case in hand is a purely mathematical problem, further physical interpretation of which is of a fundamental value.

关键词： Gravity Electron Irremovable Space-Time Curvature Spectrum

深冷轧制和热处理获得具有二级纳米结构的2024铝合金超强板材

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Transactions of Nonferrous Metals Society of China 2020年第1期30卷 14-26页

作者： stanislav KRYMSKIY Oleg SITDIKOV Elena AVTOKRATOVA Michael MARKUSHEV Institute for Metals Superplasticity Problems Russian Academy of Sciences39 Khalturin str.Ufa 450001Russia

在液氮温度和应变为2条件下对预淬火热压2024铝合金进行轧制,研究轧制和后续天然和人工时效对其结构和服役性能的影响。利用光学显微镜、电子显微镜和X射线分析发现,深冷轧制并没有定性地改变最初粗纤维组织的类型,而是在纤维内部产生... 详细信息

在液氮温度和应变为2条件下对预淬火热压2024铝合金进行轧制,研究轧制和后续天然和人工时效对其结构和服役性能的影响。利用光学显微镜、电子显微镜和X射线分析发现,深冷轧制并没有定性地改变最初粗纤维组织的类型,而是在纤维内部产生发育良好的纳米晶胞亚结构。进一步时效导致初步过饱和、加工硬化铝固溶体的分解,也导致静态回复和/或再结晶基体中强化相的沉淀。相比于压制和Т6热处理态的合金,轧制和自然时效态的合金表现出更高的屈服强度(YS=590 MPa)和极限抗拉强度(UTS=640 MPа),而两种合金的断裂伸长率相当(El^6%)。低于常规T6路线温度的人工时效可以进一步提高合金的强度且保持良好的综合力学性能,包括较高的强度(YS=610MPa,UTS=665MPа)与延性(El^10%)、良好的静态裂纹阻力(裂纹形成和生长功分别为42和18k J/m^2)和良好的耐腐蚀性(晶间腐蚀的强度和深度分别为23%和50μm)。

关键词：铝合金深冷轧制热处理纳米结构力学行为晶间腐蚀

Online search tool for graphical patterns in electronic band structures

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npj Computational Materials 2018年第1期4卷 272-279页

作者： stanislav S.Borysov Bart Olsthoorn M.Berk Gedik R.Matthias Geilhufe Alexander V.Balatsky Nordita KTH Royal Institute of Technology and Stockholm UniversityRoslagstullsbacken 23SE-10691 StockholmSweden Department of Physics Stockholm UniversitySE-10691 StockholmSweden Department of Computer Science KTH Royal Institute of TechnologySE-10044 StockholmSweden Department of Physics University of ConnecticutStorrsCT 06269USA Department of Management Engineering Technical University of DenmarkDTU2800 Kgs.LyngbyDenmark

Many functional materials can be characterized by a specific pattern in their electronic band structure,for example,Dirac materials,characterized by a linear crossing of bands;topological insulators,characterized by a“Mexican hat”pattern or an effectively free electron gas,characterized by a parabolic *** find material realizations of these features,manual inspection of electronic band structures represents a relatively easy task for a small number of ***,the growing amount of data contained within modern electronic band structure databases makes this approach *** address this problem,we present an automatic graphical pattern search tool implemented for the electronic band structures contained within the Organic Materials *** tool is capable of finding user-specified graphical patterns in the collection of thousands of band structures from high-throughput calculations in the online *** this tool,it only takes a few seconds to find an arbitrary graphical pattern within the ten electronic bands near the Fermi level for 26,739 organic *** source code of the developed tool is freely available and can be adapted to any other electronic band structure database.

关键词： graphical electronic bands

Bioinspired Water-soluble Polymers with Grafted Polyamine Chains： Synthesis and Complexation with Oligonucleotides

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Chinese Journal of Polymer Science 2018年第10期36卷 1114-1122页

作者： Vadim V.Annenkov Uma Maheswari Krishnan Viktor A.Pal'shin stanislav N.Zelinskiy Gayathri Kandasamy Elena N.Danilovtseva Limnological Institute of the Siberian Branch of the Russian Academy of Sciences 3 Ulan-Batorskaya St. P.O. Box 278 Irkutsk 664033 Russia Centre for Nanotechnology & Advanced Biomaterials (CeNTAB) School of Chemical and Biotechnology SASTRA University Thanjavur - 613401 Tamil Nadu India

The siliceous frustules of diatom algae contain complex proteins known as silaffins, which consist of a peptide chain with grafted polyamine chains. These polyamines contain twenty or more nitrogen atoms with trimethylene groups between the nitrogens. We synthesized a set of polymers containing grafted long-chain polyamine fragments by using acryloyl chloride （ACh） polymers and activated acrylic acid copolymers as the starting materials. The new polymers contained 0.05 mol%-3.2 mol% of polyamine chains, which corresponded to 0.06-3.56 mmol·g- 1 amine groups. The new amine-containing polymers formed complexes with short （19-21-mer） deoxyribonucleic acid （DNA） and ribonucleic acid （RNA） strands, and these complexes penetrated into model yeast cells and A549 lung cancer cell. This study demonstrates the potential of these species based on long-chain polyamines to serve as novel gene delivery systems.

关键词： Polyamine Polymeric amine Gene delivery Acryloyl chloride

Poly(1-vinylimidazole) Prospects in Gene Delivery

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Chinese Journal of Polymer Science 2019年第7期37卷 637-645页

作者： Elena N.Danilovtseva stanislav N.Zelinskiy Viktor A.Pal'shin Gayathri Kandasamy Uma Maheswari Krishnan Vadim V.Annenkov Limnological Institute of the Siberian Branch of the Russian Academy of Sciences 3Ulan-Batorskaya St.P.O. Box 278Irkutsk 664033Russia Centre for Nanotechnology &Advanced Biomaterials (CeNTAB) School of Chemical and BiotechnologySASTRA UniversityThanjavur 613401 Tamil NaduIndia

Polymeric amines are being studied intensively as components of systems for gene delivery in genetic engineering and gene therapy of genetic disorders, including cancer. Despite remarkable achievements in the field, polymeric amines, such as polyethyleneimine, show some disadvantages. Strong interaction between the amine-containing polymer and nucleic acid hampers the release of nucleic acid in the cell cytoplasm. Amine groups can interact with the cell membrane which results in cell death. These limitations of polymeric amines stimulated an investigation of new structures for gene delivery. Imidazole-containing polymers have attracted attention as lesser basic substances, while they are able to interact with polymeric acids. Further development of imidazole-based gene delivery agents requires knowledge about some fundamental aspects of interaction between nucleic acids, and polymeric imidazoles. In this work, we studied the complexation of poly(1-vinylimidazole) and oligomeric DNA. We found that the number of active sites capable of binding with negatively charged phosphate groups is comparable with the number of protonated imidazole units in the case of high molecular weight polymer. The increase in polymer charge by 1-bromopropane quaternizating 1%?5% imidazole units or by decreasing the pH to 6.5?7 considerably increased the ability of poly(1-vinylimidazole) to interact with oligonucleotides. The pH sensitivity of this interaction is interesting for cancer gene therapy because the tumours have a lowered intercellular pH (stable oligonucleotide complex) and a higher extracellular pH which can lead to complex dissociation. Minimal critical length for complexation of quaternized poly(1-vinylimidazole) and DNA is below eight units which corresponds to polymers with amine groups. Fluorescence-tagged poly(1-vinylimidazole) samples were obtained and their potential for monitoring the polymer and polymer-oligonucleotide complex internalization into living cells was demo

关键词： Polymeric amines Oligonucleotides Fluorescence Poly(1-vinylimidazole) Gene delivery

Assessment and forecast of changes of reservoir volumes due to thermal settling in permafrost areas of Russia

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Research in Cold and Arid Regions 2014年第5期6卷 428-431页

作者： Ilja S.Sobol stanislav V.Sobol Nizhny Novgorod State University of Architecture and Civil Engineering

This paper presents the results of data analyses and assessments of field and theoretical researches on reservoir bed relief transformation due to thermal settling in the permafrost regions of *** resulting changes（increases） of the total volumes of large and small reservoirs are quantified,of which information will be of great use in future reservoir design and exploitation.

关键词： permafrost reservoir age volume increase

Histological differentiation impacts the tumor immune microenvironment in gastric carcinoma:Relation to the immune cycle

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World Journal of Gastroenterology 2021年第31期27卷 5259-5271页

作者： Artem Mashukov Dmytro Shapochka Oleksii Seleznov Nazarii Kobyliak Tetyana Falalyeyeva stanislav Kirkilevsky Roman Yarema Oksana Sulaieva Department of Oncology Odessa National Medical UniversityOdessa 65082Ukraine Department of Molecular Pathology and Genetics Medical Laboratory CSDKyiv 03022Ukraine Department of Pathology Medical Laboratory CSDKyiv 03022Ukraine Department of Endocrinology Bogomolets National Medical UniversityKyiv 01601Ukraine Biomedicine Educational-Scientific Center"Institute of Biology and Medicine"Taras Shevchenko National University of KyivKyiv 01601Ukraine Department of Thoracic Tumors National Cancer InstituteKyiv 03022Ukraine Department of Oncology and Medical Radiology Danylo Halytsky Lviv National Medical UniversityLviv 79010Ukraine

BACKGROUND Various histological types of gastric carcinomas(GCs)differ in terms of their pathogenesis and their preexisting background,both of which could impact the tumor immune microenvironment(TIME).However,the current understanding of the immune contexture of GC is far from *** To clarify the tumor-host immune interplay through histopathological features and the tumor immune cycle *** In total,50 GC cases were examined(15 cases of diffuse GC,31 patients with intestinal-type GC and 4 cases of mucinous GC).The immunophenotype of GC was assessed and classified as immune desert(ID),immune excluded(IE)or inflamed(Inf)according to CD8+cell count and spatial *** addition,CD68+and CD163+macrophages and programmed death-ligand 1(PD-L1)expression were *** We found that GCs with different histological differentiation demonstrated distinct immune *** intestinal-type GCs had inflamed TIMEs rich in both CD8+cells and *** contrast,more aggressive diffuse-type GC more often possessed ID characteristics with few CD8+lymphocytes but abundant CD68+macrophages,while mucinous GC had an IE-TIME with a prevalence of CD68+macrophages and CD8+lymphocytes in the peritumor ***-L1 expression prevailed mostly in intestinal-type Inf-GC,with numerous CD163+cells ***,GCs of different histological patterns have specific mechanisms of immune *** intestinal-type GC was more often related to PD-L1 expression,diffuse and mucinous GCs possessing more aggressive behavior demonstrated low immunogenicity and a lack of tumor antigen recognition or immune cell recruitment into the tumor *** These data help to clarify the links between tumor histogenesis and immunogenicity for a better understanding of GC biology and more tailored patient management.

关键词： Gastric carcinoma Tumor immune microenvironment Tumor infiltrating lymphocytes Tumor associated macrophages