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For any locality-preserving action of a group $G$ on a quantum spin chain one can define an anomaly index taking values in the group cohomology of $G$. The anomaly index is a kinematic quantity, it does not depend on the Hamiltonian. We prove that a nonzero anomaly index prohibits any $G$-invariant Hamiltonian from having $G$-invariant gapped ground states. Lieb-Schultz-Mattis-type theorems are a special case of this result when $G$ involves translations. In the case when the symmetry group $G$ is a Lie group, we define an anomaly index which takes values in the differentiable group cohomology as defined by J.-L. Brylinski and prove a similar result., Comment: 41 pages, 3 figures

We show that for families of 1d lattice systems in an invertible phase, the cohomology class of the higher Berry curvature can be refined to an integral degree-3 class on the parameter space. Similarly, for families of U(1)-invariant 2d lattice systems in an invertible phase, the higher Thouless pump can be refined to an integral degree-2 class on the parameter space. We show that the 2d Thouless pump can be identified with an excess Berry curvature of a flux insertion., Comment: v2: typos corrected, exposition improved, examples of families with nonzero higher Berry class and higher Thouless pump added. Version accepted to Comm. Math. Phys

We study the possibility of spontaneous symmetry breaking in systems with both charge and dipole symmetries. For $d$-dimensional systems at a positive temperature, we show that charge symmetry cannot be spontaneously broken for $d\leq 4$, while dipole symmetry cannot be spontaneously broken for $d\leq 2$. For $T=0$, we show that charge symmetry cannot be spontaneously broken for $d\leq 2$ if the compressibility is finite. We also show that continuum systems with a dipole symmetry have infinite inertial mass density., Comment: Reworked introduction and added references

We study novel effects in non-centrosymmetric superconductors arising from their unique coupling of Cooper-pair condensate and elasticity. We show that although the much discussed Lifshitz coupling is not observable in a uniform bulk state, it strikingly endows dislocations with a fractional magnetic flux. We also predict a generation of voltage-free strain by a DC current in a P and T-breaking Josephson junction. Viewing superconductors through the lens of higher-form symmetries we identify the Lifshitz coupling as a chemical potential for the approximately conserved winding number, drawing an analogy with pyroelectric insulators.

A clinical research requires a systematic approach with diligent planning, execution and sampling in order to obtain reliable and validated results, as well as an understanding of each research methodology is essential for researchers. Indeed, selecting an inappropriate study type, an error that cannot be corrected after the beginning of a study, results in flawed methodology. The results of clinical research studies enhance the repertoire of knowledge regarding a disease pathogenicity, an existing or newly discovered medication, surgical or diagnostic procedure or medical device. Medical research can be divided into primary and secondary research, where primary research involves conducting studies and collecting raw data, which is then analysed and evaluated in secondary research. The successful deployment of clinical research methodology depends upon several factors. These include the type of study, the objectives, the population, study design, methodology/techniques and the sampling and statistical procedures used. Among the different types of clinical studies, we can recognize descriptive or analytical studies, which can be further categorized in observational and experimental. Finally, also pre-clinical studies are of outmost importance, representing the steppingstone of clinical trials. It is therefore important to understand the types of method for clinical research. Thus, this review focused on various aspects of the methodology and describes the crucial steps of the conceptual and executive stages.

Animal experimentation is widely used around the world for the identification of the root causes of various diseases in humans and animals and for exploring treatment options. Among the several animal species, rats, mice and purpose-bred birds comprise almost 90% of the animals that are used for research purpose. However, growing awareness of the sentience of animals and their experience of pain and suffering has led to strong opposition to animal research among many scientists and the general public. In addition, the usefulness of extrapolating animal data to humans has been questioned. This has led to Ethical Committees' adoption of the 'four Rs' principles (Reduction, Refinement, Replacement and Responsibility) as a guide when making decisions regarding animal experimentation. Some of the essential considerations for humane animal experimentation are presented in this review along with the requirement for investigator training. Due to the ethical issues surrounding the use of animals in experimentation, their use is declining in those research areas where alternative in vitro or in silico methods are available. However, so far it has not been possible to dispense with experimental animals completely and further research is needed to provide a road map to robust alternatives before their use can be fully discontinued.

The system of dry ash–slag removal at the Reftinskaya state district power plant which provides capture, storage and shipment of fly ash to the consumers is considered in this study. The results of determination of chemical and phase composition, physical properties, melting temperature and activity of natural radionuclides of ash which is form during burning of stone coal of Ekibastuz basin are presented. Ash is acidic, superfine and refractory one with a low content of combustible substance. As to composition and properties it satisfies the requirements of Russian Standard no. 25818 and ships to consumers under Technical Conditions 5717–004–79935691–2009. The results of laboratory tests and industrial production of building materials and products on the basis of ash of Reftinskaya state district power plant are presented. It is shown that ash is used in the production of Portland cement, heavy and cellular autoclave concrete, dry mixes and can also be used as part of fly ash non-fired and agloporite gravel, ceramic bricks. The features of their production, basic physical and mechanical properties of building materials and products are described. It is shown that the introduction of a new system of dry ash removal at the state district power plant contributes to the expansion of directions and increase in the volume of ash recycling.

Одной из самых актуальных тем в современной педагогической науке является тема мотивационно-ценностного отношения учащихся к учебной деятельности. Наблюдение за работой учителей показывает, что они далеко не всегда уделяют должного внимания мотивации своих учащихся. В данной статье говорится о факторах, которые влияют на отношение к школе и рекомендации по предупреждению нелюбви к школе.

В статье освящена проблема математической лингвистики как вспомогательного педагогического инструмента при обучении иностранному языку в рамках БТО в неязыковом вузе.

В статье освящена проблематика цифровизации высшего образования. применительно к плавному преобразованию системы ЗО (заочного обучения) в систему ДО (дистанционного обучения) средствами ЭОР (электронно-образовательных ресурсов).

We study the localization properties of the equal-time electron Green’s function in a Chern insulator in an arbitrary dimension and with an arbitrary number of bands. We prove that the Green’s function cannot decay super-exponentially if the Hamiltonian is finite-range and the quantum Hall response is nonzero. For a general band Hamiltonian (possibly infinite-range), we prove that the Green’s function cannot be finite-range if the quantum Hall response is nonzero. The proofs use methods of algebraic geometry.

The article deals with the development of approaches to the formation of the textual-discursive space of a linguistic personality. Any text from a certain discourse acquires special dimensions while preserving its constitutive characteristics. The authors have determined that the qualification of the discourse as speech materialized in written or oral form with the corresponding socio-cultural, psychological, mental, and other factors is valid. The analysis of the implementation of various text thematic progressions makes it possible to classify texts according to the dominance of a certain thematic progression. The study of the entire set of thematic progressions with the establishment of their functional load determines the patterns of text structuring, the presence of their normative models and codification, and the implementation of certain progression models in the text space., O artigo trata do desenvolvimento de abordagens para a formação do espaço textual-discursivo de uma personalidade linguística. Qualquer texto de um determinado discurso adquire dimensões especiais, preservando suas características constitutivas. Os autores determinaram que a qualificação do discurso como discurso materializado na forma escrita ou oral com os correspondentes fatores socioculturais, psicológicos, mentais e outros é válida. A análise da implementação de várias progressões temáticas textuais permite classificar os textos de acordo com o domínio de uma determinada progressão temática. O estudo de todo o conjunto de progressões temáticas com o estabelecimento de sua carga funcional determina os padrões de estruturação do texto, a presença de seus modelos normativos e de codificação e a implementação de determinados modelos de progressão no espaço textual., El artículo trata sobre el desarrollo de aproximaciones a la formación del espacio textual-discursivo de una personalidad lingüística. Cualquier texto de un determinado discurso adquiere dimensiones especiales conservando sus características constitutivas. Los autores han determinado que es válida la calificación del discurso como discurso materializado en forma escrita u oral con los correspondientes factores socioculturales, psicológicos, mentales, entre otros. El análisis de la implementación de diversas progresiones temáticas de textos permite clasificar los textos según el predominio de una determinada progresión temática. El estudio de todo el conjunto de progresiones temáticas con el establecimiento de su carga funcional determina los patrones de estructuración del texto, la presencia de sus modelos normativos y codificación, y la implementación de ciertos modelos de progresión en el espacio textual.

We study the localization properties of the equal-time electron Green’s function in a Chern insulator in an arbitrary dimension and with an arbitrary number of bands. We prove that the Green’s function cannot decay super-exponentially if the Hamiltonian is finite-range and the quantum Hall response is nonzero. For a general band Hamiltonian (possibly infinite-range), we prove that the Green’s function cannot be finite-range if the quantum Hall response is nonzero. The proofs use methods of algebraic geometry.

Structure of Guests in MOF and Their ApplicationsbyIevgen KapustinDoctor of Philosophy in ChemistryUniversity of California, BerkeleyProfessor Omar M. Yaghi, Chair Chapter 1. Introduction to the fundamentals of reticular chemistry, metal-organic frameworks (MOFs), crystallographic studies of MOFs, and sorption studies of MOFs. Chapter 2. MOF-520 is used to coordinatively bind and align molecules of varying size, complexity, and functionality. The reduced motional degrees of freedom obtained with this coordinative alignment method allow the structures of molecules to be determined by single-crystal x-ray diffraction techniques. The chirality of the MOF backbone also serves as a reference in the structure solution for an unambiguous assignment of the absolute configuration of bound molecules. Sixteen molecules representing four common functional groups (primary alcohol, phenol, vicinal diol, and carboxylic acid), ranging in complexity from methanol to plant hormones (gibberellins, containing eight stereocenters), are crystallized and have their precise structure determined. Single and double bonds in gibberellins can be distinguished crystallographically. A racemic mixture of jasmonic acid is crystallized enantioselectively and its absolute configuration is determined for the first time.Chapter 3. Despite numerous studies on chemical and thermal stability of MOF, mechanical stability remains largely undeveloped. To date, no strategy exists to control the mechanical deformation of MOFs under ultrahigh pressure. Here, we show that the mechanically unstable MOF-520 can be retrofitted by precise placement of a rigid 4,4′-biphenyldicarboxylate (BPDC) linker as a “girder” to afford a mechanically robust framework: MOF-520-BPDC. This retrofitting alters how the structure deforms under ultrahigh pressure and thus leads to a drastic enhancement of its mechanical robustness. While in the parent MOF-520 the pressure transmitting medium molecules diffuse into the pore and expand

The properties of mineral wool sawdust, formed during sawing of heat-insulating slabs at two enterprises, and its influence on the physical and mechanical properties of an oil- well mortar and cement stone are determined. Mineral wool sawdust has a low bulk density, fiber diameter 10-12 microns, fiber length is from 5 to 12 mm. It is shown that the introduction of mineral wool sawdust in the amount of up to 1.5 % of the cement mass slightly reduces the spreading and density, increases the water separation of the grouting mortar, increases the bending and compressive strength of the cement stone up to 28 and 41 %, respectively. It is recommended to use the mineral fertilizer sawdust of 'TIZOL' JSC in the amount of 1-1.5% as a reinforcing additive in the composition of oil-well cement. © Published under licence by IOP Publishing Ltd.

We study aspects of Berry phase in gapped many-body quantum systems by means of effective field theory. Once the parameters are promoted to spacetime-dependent background fields, such adiabatic phases are described by Wess-Zumino-Witten (WZW) and similar terms. In the presence of symmetries, there are also quantized invariants capturing generalized Thouless pumps. Consideration of these terms provides constraints on the phase diagram of many-body systems, implying the existence of gapless points in the phase diagram which are stable for topological reasons. We describe such diabolical points, realized by free fermions and gauge theories in various dimensions, which act as sources of "higher Berry curvature" and are protected by the quantization of the corresponding WZW terms or Thouless pump terms. These are analogous to Weyl nodes in a semimetal band structure. We argue that in the presence of a boundary, there are boundary diabolical points---parameter values where the boundary gap closes---which occupy arcs ending at the bulk diabolical points. Thus the boundary has an "anomaly in the space of couplings" in the sense of C\'ordova et al. Consideration of the topological effective action for the parameters also provides some new checks on conjectured infrared dualities and deconfined quantum criticality in 2+1d., Comment: 21+7 pages, 4+2 figures

We define and study analogs of the Thouless charge pump for many-body gapped systems in dimension $D$. We show how to attach a topological invariant to a $D$-dimensional family of such systems, provided all of them have an on-site $U(1)$ symmetry. For a large class of families we argue that this topological invariant is an integer. In the case of gapped systems of free fermions in two dimensions, the invariant can be expressed in terms of the curvature of the Bloch-Berry connection. We also obtain a new formula for the Thouless charge pump in 1d which involves only static linear response and is analogous to the Streda formula for Hall conductivity., Comment: 32 pages

A family of finite-dimensional quantum systems with a non-degenerate ground state gives rise to a closed 2-form on the parameter space: the curvature of the Berry connection. Its cohomology class is a topological invariant of the family. We seek generalizations of the Berry curvature to families of gapped many-body systems in D spatial dimensions. Field theory predicts that in spatial dimension D the analog of the Berry curvature is a closed (D+2)-form on the parameter space (the Wess-Zumino-Witten form). We construct such closed forms for arbitrary families of interacting lattice systems in all dimensions. In the special case of systems of free fermions in one dimension, we show that these forms can be expressed in terms of the Bloch-Berry connection on the product of the Brillouin zone and the parameter space. In the case of families of Short-Range Entangled systems, we argue that integrals of our forms over spherical cycles are quantized., Comment: 22 pages. v2: minor inaccuracies and typos fixed, references added

В статье представлены результаты педагогического эксперимента, который был направлен на проверку эффективности применения разработанной методики в тренировочном процессе юношей, занимающихся лакроссом. Представлены материалы, характеризующие степень влияния данной методики на физическую, техническую и тактическую подготовку игроков.

Unimolecular decomposition pathways are challenging to address in transition-metal catalysis and have previously not been suppressed via incorporation into a solid support. Two robust metal-organic frameworks (IRMOF-10 and bio-MOF-100) are used for the architectural stabilization of a structurally well-defined gold(III) catalyst. The inherent rigidity of these materials is utilized to preclude a unimolecular decomposition pathway - reductive elimination. Through this architectural stabilization strategy, decomposition of the incorporated gold(III) catalyst in the metal-organic frameworks is not observed; in contrast, the homogeneous analogue is prone to decomposition in solution. Stabilization of the catalyst in these metal-organic frameworks precludes leaching and enables recyclability, which is crucial for productive heterogeneous catalysis.

Field studies on the pre-operational period of a Belarusian NPP have allowed us to determine the “background” level of gamma-emitting radionuclides in individual components of the environment. The results of measuring the dose rate at the NPP construction site are from 0.048 to 0.089 μSv/h. External radiation in the surveyed area is at 96% due to 40K, 226Ra and 232Th. The radionuclides in the surface soil layer are: 40K - from 530 to 700 Bq/kg; 226Ra - from 30 to 55 Bq/kg; and 232Th - from 17 to 35 Bq/kg; 137Cs from 2 to 13 Bq/kg. The dose rate in the floodplain of the Viliya River from 0.033 to 0.082 μSv/h. The activity concentrations of the radionuclides in the surface soil layer of the floodplain of the Viliya River are: 40K - from 390 to 690 Bq/kg; 226Ra - from 33 to 50 Bq/kg; 232Th - from 15 to 50 Bq/kg; 137Cs - from 3 to 12 Bq/kg. The activity concentration of carbon-14 and tritium in the dominant vegetation species were determined to be: from 74.4 to 111.5 pMC and less than lower range limit, respectively. © 2020 RAD Conference Proceedings.

Nowadays about 200 million tons of phosphogypsum (PG) have been stored in the dumps of the chemical industry and non–ferrous metallurgy of Russia which pollutes the environment. This waste contains up to 98 % of two–water gypsum and impurities including rare earth metals (REM) in an amount of up to 0.5 % preventing its use in the production of building materials. A complex technology of FG recycling including extraction of REM, neutralization and dehydration of the pulp for using in the production of gypsum binders and Portland cement. Results of determination of density, grain, chemical and mineral compositions and structure of the product of recycling of FG of the “Sredneuralsky copper smelting plant” are presented. After the REM extraction, the PG is a loose lumpy mass with moisture content of 28–32 % which contains about 10 % of particles larger than 40 mm and not more than 60 % of particles less than 10 mm, it has a true density of 2.26 g/cm3, pH of aqueous extract is 5.95. It has the following chemical composition, mass. %: 0.87 SiО2; 0.93 A12O3; 0.20 Fe2O3; 31.00 CaO; 0.034 MgO; 44.27 SО3; 0.10 K2О; 0.42 Nа2О; 0.45 Р2О5(general); 20.73 of mass loss of ignition. The mineral composition of the PG processing product is represented by two-water gypsum and a slight amount of quartz. The possibility of using gypsum–containing waste in the production of gypsum binders and cement is considered. The effect of temperature and duration of firing, the dispersion, the type and quantity of chemical and mineral admixtures on physical and mechanical properties of gypsum binder, the influence of the type and amount of mineral additive on pelletizing and physic–mechanical properties of the granulated and pressed PG and its effects on setting time and strength of Portland cement are represented. It is recommended to use PG to obtain low–temperature and composite gypsum binders, regulation of Portland cement setting after extraction of REM.

Physical properties, grain, chemical and mineral compositions of blast-furnace slags selected from the dumps of JSC 'EVRAZ Nizhny Tagil metallurgical plant' and PJSC 'Nadezhdinski Metallurgical Plant' were studied. Also, the same parameters of granulated blast-furnace slag of JSC 'Mechel-Materialy' currently used by cement plants in the Ural region as a mineral additive during Portland cement grinding were investigated. By chemical composition all of them are acidic. In contrast to granulated slag which mainly contains the vitreous phase dump slags are well crystallized and mainly contain the minerals okermanite, mervinite and monticellite. Dump slags have a Student's t-criterion of more than 15.0, i.e. they can be used as a mineral additive during Portland cement grinding. The introduction of 20 % of the studied slags reduces the water demand of Portland cement of joint grinding and accelerates the setting of the cement paste, reduces the bending and compression strength compared to the additive-free cement. Slag-containing cements after 7 and 28 days of hardening have similar values of compressive strength: 27.2-29.2 and 41.1-43.0 MPa respectively, they are normally hardening and have a strength class of 42.5. Chemical, physical and mechanical properties of these cements meet the requirements of Russian Standard 31108-2016. © Published under licence by IOP Publishing Ltd.

When producing iron ore concentrate at Kachkanarsk integrated mining works 2 types of wastes are formed, namely: final tailings of dry magnetic separation (DMS) and final tailings of wet magnetic separation (WMS). Final tailings of wet magnetic separation (WMS) are pulled off or dumped into disposal area up to 45mln tons annually causing great damages to the environment. These final tailings are finely dispersed materials, their chemical composition is oxides of silicon, aluminium, calcium and iron in general. All this allows to use the wastes under consideration to produce Portland cement clinker replacing clayey and iron components in the raw material mixture completely and limestone partially. The replacement of clay with final tailings of ore enrichment are suitable to manufacture clinker raw material mixture allowing to use two-component raw mix instead of three-component and four-component one thus simplifying the technology of cement production and improving the ecological situation in Sverdlovsk region. The utilization of final tailings for concentration of titano-magnetite ores decreases fuel consumption when burning clinker compared to the traditional compositions. Experimental cement meets all the requirements of the Russian Standard 10178 as to their chemical and physic-mechanical properties and have grade 500. © Published under licence by IOP Publishing Ltd.

The composition and properties of the tailings of quartzite enrichment of "Gora Karaul'naya"deposit, the possibility of its using as an aggregate in the composition of heavy and fine-aggregate concrete and dry construction mixture were determined. The introduction of quartzite tailings increases the water demand of the mixture, reduces the compressive strength of concrete and mortar, increases the bending strength compared to quartz sand. © Published under licence by IOP Publishing Ltd.

The JSC “DINUR” use enriched quartzite from the “Gora Karaul’naya” deposit in the production of dinas refractories. The tailings of quartzite enrichment are stored in the dump, not used, and thereby pollute the environment. Chemical, mineral and grain composition, physical, mechanical and technological properties of samples of quartzite tailings of the current output and selected from the dump are determined in this study. The tailings of current output contain less oxides of aluminum, iron and calcium and alkalis compared to the dump tailings. Their mineral composition is mainly represented by quartz as well as impurities of muscovite, hematite, magnetite, chlorite, shungite, zircon, rutile, pyrite with a total content of up to 3 %. The dump quartzite tailings contain particles less than 5 mm in size with a predominance of dust–like fractions (less than 0.16 mm). As to the grain composition, content of dust and clay particles, clay lumps and impurities tailings of the current output meets the requirements of Russian Standard no. 31424 (for the sand from sifting of crushing solid stone), belong to the class II, group of large sands; dump tailings belong to class I and the group of medium sands. Up to 30 % of the particles are plate– and needle–shaped. The features of changes in chemical composition, bulk density, content of dust–like, clay and organic impurities depending on the size of tailings fractions are considered. The possibility of using of tailings of quartzite enrichment as sand for construction works and fine fractions of tailings as molding material in foundry and granular loading in pressure and non−pressure filters for water purification is shown.

Despite numerous studies on chemical and thermal stability of metal-organic frameworks (MOFs), mechanical stability remains largely undeveloped. To date, no strategy exists to control the mechanical deformation of MOFs under ultrahigh pressure. Here, we show that the mechanically unstable MOF-520 can be retrofitted by precise placement of a rigid 4,4'-biphenyldicarboxylate (BPDC) linker as a "girder" to afford a mechanically robust framework: MOF-520-BPDC. This retrofitting alters how the structure deforms under ultrahigh pressure and thus leads to a drastic enhancement of its mechanical robustness. While in the parent MOF-520 the pressure transmitting medium molecules diffuse into the pore and expand the structure from the inside upon compression, the girder in the new retrofitted MOF-520-BPDC prevents the framework from expansion by linking two adjacent secondary building units together. As a result, the modified MOF is stable under hydrostatic compression in a diamond-anvil cell up to 5.5 gigapascal. The increased mechanical stability of MOF-520-BPDC prohibits the typical amorphization observed for MOFs in this pressure range. Direct correlation between the orientation of these girders within the framework and its linear strain was estimated, providing new insights for the design of MOFs with optimized mechanical properties.

Objective-The drug warfarin blocks carboxylation of vitamin K-dependent proteins and acts as an anticoagulant and an accelerant of vascular calcification. The calcification inhibitor MGP (matrix Gla [carboxyglutamic acid] protein), produced by vascular smooth muscle cells (VSMCs), is a key target of warfarin action in promoting calcification; however, it remains unclear whether proteins in the coagulation cascade also play a role in calcification.Approach and Results-Vascular calcification is initiated by exosomes, and proteomic analysis revealed that VSMC exosomes are loaded with Gla-containing coagulation factors: IX and X, PT (prothrombin), and proteins C and S. Tracing of Alexa488-labeled PT showed that exosome loading occurs by direct binding to externalized phosphatidylserine (PS) on the exosomal surface and by endocytosis and recycling via late endosomes/multivesicular bodies. Notably, the PT Gla domain and a synthetic Gla domain peptide inhibited exosome-mediated VSMC calcification by preventing nucleation site formation on the exosomal surface. PT was deposited in the calcified vasculature, and there was a negative correlation between vascular calcification and the levels of circulating PT. In addition, we found that VSMC exosomes induced thrombogenesis in a tissue factor-dependent and PS-dependent manner.Conclusions-Gamma-carboxylated coagulation proteins are potent inhibitors of vascular calcification suggesting warfarin action on these factors also contributes to accelerated calcification in patients receiving this drug. VSMC exosomes link calcification and coagulation acting as novel activators of the extrinsic coagulation pathway and inducers of calcification in the absence of Gla-containing inhibitors.

A long time ago F. Bloch showed that in a system of interacting non-relativistic particles the net particle-number current must vanish in any equilibrium state. Bloch's argument does not generalize easily to the energy current. We devise an alternative argument which proves the vanishing of the net energy currents in equilibrium states of lattice systems as well as systems of non-relativistic particles with finite-range potential interactions. We discuss some applications of these results. In particular, we show that neither a 1d lattice system nor a 1d system of non-relativistic particles with finite-range potential interactions can flow to a Conformal Field Theory with unequal left-moving and right-moving central charges., Comment: 6 pages. Shortened and streamlined version published in Physical Review Letters

В статье представлены результаты педагогического эксперимента, направленного на проверку эффективности использования народных игр в процессе физического воспитания детей старшего дошкольного возраста и их влияния на познавательную сферу ребенка.

В статье представлены результаты исследования значимых количественных и качественных показателей, определяющих уровень мастерства хоккеистов в атаке, и в целом эффективность игровой деятельности хоккеистов различных команд.

В статье представлены результаты проведенного педагогического эксперимента, направленного на развитие памяти и мышления у детей младшего школьного возраста средствами спортивного ориентирования.

Sorbent-assisted water harvesting from air represents an attractive way to address water scarcity in arid climates. Hitherto, sorbents developed for this technology have exclusively been designed to perform one water harvesting cycle (WHC) per day, but the productivities attained with this approach cannot reasonably meet the rising demand for drinking water. This work shows that a microporous aluminum-based metal-organic framework, MOF-303, can perform an adsorption-desorption cycle within minutes under a mild temperature swing, which opens the way for high-productivity water harvesting through rapid, continuous WHCs. Additionally, the favorable dynamic water sorption properties of MOF-303 allow it to outperform other commercial sorbents displaying excellent steady-state characteristics under similar experimental conditions. Finally, these findings are implemented in a new water harvester capable of generating 1.3 L kgMOF -1 day-1 in an indoor arid environment (32% relative humidity, 27 °C) and 0.7 L kgMOF -1 day-1 in the Mojave Desert (in conditions as extreme as 10% RH, 27 °C), representing an improvement by 1 order of magnitude over previously reported devices. This study demonstrates that creating sorbents capable of rapid water sorption dynamics, rather than merely focusing on high water capacities, is crucial to reach water production on a scale matching human consumption.

Non-fired fly ash gravel was obtained on the basis of fly ash of thermal power plant no 5 of JSC "SIBEKO", 15 % of Portland cement and the hardening accelerator. The gravel of 5-20 mm fraction and 6 months' air-moist curing is 900 density grade, P300 strength grade, frost-resistance grade - F35. The compositions of cement concretes of strength class from B10 to B25 were established and their physical and mechanical properties were determined using obtained non-fired fly ash gravel. They belong to the lightweight concrete according to the density (1817-1857 kg/m3). The introduction of superplasticizer SP-1 reduces water demand of concrete mixture and increases strength of concrete on fly ash gravel. © 2019 Published under licence by IOP Publishing Ltd.

The possible trends to improve the building-technical properties of dry ashes characteristics formed as a result of solid fuel combustion at thermal power stations are presented. The results of different fly-ash conditioning technologies application to widen the trends and to increase the volumes of their use in the construction materials and products., Представлены возможные направления улучшения строительно-технических характеристик сухих зол, образующихся при сжигании твердого топлива на тепловых электростанциях. Приведены результаты применения различных технологий кондиционирования свойств золы для расширения направлений и увеличения объемов их использования при производстве строительных материалов и изделий.

In this introductory article we present the basics of an approach to implementing computational interpreting of natural language aiming to model the meanings of words and phrases. Unlike other approaches, we attempt to define the meanings of text fragments in a composable and computer interpretable way. We discuss models and ideas for detecting different types of semantic incomprehension and choosing the interpretation that makes most sense in a given context. Knowledge representation is designed for handling context-sensitive and uncertain / imprecise knowledge, and for easy accommodation of new information. It stores quantitative information capturing the essence of the concepts, because it is crucial for working with natural language understanding and reasoning. Still, the representation is general enough to allow for new knowledge to be learned, and even generated by the system. The article concludes by discussing some reasoning-related topics: possible approaches to generation of new abstract concepts, and describing situations and concepts in words (e.g. for specifying interpretation difficulties)., Comment: 26 pages

We describe a 3d analog of the Jordan-Wigner transformation which maps an arbitrary fermionic system on a 3d spatial lattice to a 2-form $\mathbb{Z}_2$ gauge theory with an unusual Gauss law. An important property of this map is that it preserves the locality of the Hamiltonian. The map depends explicitly on the choice of a spin structure of the spatial manifold. We give examples of 3d bosonic systems dual to free fermions. We also describe the corresponding Euclidean lattice models, which is analogous to the generalized Steenrod square term in (3+1)D (compared to the Chern-Simon term in (2+1)D)., Comment: 12 pages, 6 figures

We study 2D fermions with a short-range interaction in the presence of a van Hove singularity. It is shown that this system can be consistently described by an effective field theory whose Fermi surface is subdivided into regions as defined by a factorization scale, and that the theory is renormalizable in the sense that all of the counterterms are well defined in the IR limit. The theory has the unusual feature that the renormalization group equation for the coupling has an explicit dependence on the renormalization scale, much as in theories of Wilson lines. In contrast to the case of a round Fermi surface, there are multiple marginal interactions with nontrivial RG flow. The Cooper instability remains strongest in the BCS channel. We also show that the marginal Fermi liquid scenario for the quasiparticle width is a robust consequence of the van Hove singularity. Our results are universal in the sense that they do not depend on the detailed properties of the Fermi surface away from the singularity., Comment: This paper supersedes arXiv:1601.03150 by the same authors, which will be withdrawn. 27 pages, 10 figures

Отметка – это показатель качества усвоения учебного материала учеником, а не характеристика ученика. Как приятно, когда ребёнок приносит хорошие отметки. Как отмечает автор, тройки, двойки – это сигнал, что ребёнку даётся трудно усвоение учебного материала. А это значит, что надо уделять больше времени образовательному процессу.

Автор статьи считает, что современной школе нужен профессионально компетентный, самостоятельно мыслящий педагог, способный к реализации гуманистических ценностей на практике, к осмысленному включению в инновационные процессы. Однако, даже при достаточно высоком уровне готовности к педагогической деятельности личностная и профессиональная адаптация молодого учителя может протекать длительно и сложно.

We have demonstrated that the microenvironment of a highly anionic supramolecular catalyst can mimic the active sites of enzymes and impart rate accelerations of a million-fold or more. However, these microenvironments can be challenging to study, especially in the context of understanding which specific features of the catalyst are responsible for its high performance. We report here the development of an experimental mechanistic probe consisting of two isostructural catalysts. When examined in parallel transformations, the behavior of these catalysts provides insight relevant to the importance of anionic host charge on reactivity. These two catalysts exhibit similar host-substrate interactions, but feature a significant difference in overall anionic charge (12- and 8-). Within these systems, we compare the effect of constrictive binding in a net neutral aza-Cope rearrangement. We then demonstrate how the magnitude of anionic host charge has an exceptional influence on the reaction rates for a Nazarov cyclization, evidenced by an impressive 680-fold change in reaction rate as a consequence of a 33% reduction in catalyst charge.

Energy-efficient production of water from desert air has not been developed. A proof-of-concept device for harvesting water at low relative humidity was reported; however, it used external cooling and was not desert-tested. We report a laboratory-to-desert experiment where a prototype using up to 1.2 kg of metal-organic framework (MOF)-801 was tested in the laboratory and later in the desert of Arizona, USA. It produced 100 g of water per kilogram of MOF-801 per day-and-night cycle, using only natural cooling and ambient sunlight as a source of energy. We also report an aluminum-based MOF-303, which delivers more than twice the amount of water. The desert experiment uncovered key parameters pertaining to the energy, material, and air requirements for efficient production of water from desert air, even at a subzero dew point.

The electronic character of porphyrin active sites for electrocatalytic reduction of CO2 to CO in a two-dimensional covalent organic framework (COF) was tuned by modification of the reticular structure. Efficient charge transport along the COF backbone promotes electronic connectivity between remote functional groups and the active sites and enables the modulation of the catalytic properties of the system. A series of oriented thin films of these COFs was found to reduce CO2 to CO at low overpotential (550 mV) with high selectivity (faradaic efficiency of 87%) and at high current densities (65 mA/mg), a performance well beyond related molecular catalysts in regard to selectivity and efficiency. The catalysts are stable for more than 12 h without any loss in reactivity. X-ray absorption measurements on the cobalt L-edge for the modified COFs enable correlations between the inductive effects of the appended functionality and the electronic character of the reticulated molecular active sites.

Water scarcity is a particularly severe challenge in arid and desert climates. While a substantial amount of water is present in the form of vapour in the atmosphere, harvesting this water by state-of-the-art dewing technology can be extremely energy intensive and impractical, particularly when the relative humidity (RH) is low (i.e., below ~40% RH). In contrast, atmospheric water generators that utilise sorbents enable capture of vapour at low RH conditions and can be driven by the abundant source of solar-thermal energy with higher efficiency. Here, we demonstrate an air-cooled sorbent-based atmospheric water harvesting device using the metal-organic framework (MOF)-801 [Zr6O4(OH)4(fumarate)6] operating in an exceptionally arid climate (10-40% RH) and sub-zero dew points (Tempe, Arizona, USA) with a thermal efficiency (solar input to water conversion) of ~14%. We predict that this device delivered over 0.25 L of water per kg of MOF for a single daily cycle.

Colorless building glass on the basis of non-standard raw materials with the use of discolourers-cerium oxide and potassium nitrate-was synthesized. The regularities of the cerium oxide addition effect on the light transmittance of the glasses are shown when the proportion of Na 2 O is replaced by K 2 O. The results of ORP and iron oxide equilibrium investigation in glasses, improvement of light transmission by means of correction of ORP glass are presented. The physical and chemical properties of glasses are measured: thermal coefficient of linear expansion (TCLE), water resistance and crystallization ability of glasses. The recommended composition of a building glass on the basis of non-standard raw materials is presented. © Published under licence by IOP Publishing Ltd.

Water scarcity is a particularly severe challenge in arid and desert climates. While a substantial amount of water is present in the form of vapour in the atmosphere, harvesting this water by state-of-the-art dewing technology can be extremely energy intensive and impractical, particularly when the relative humidity (RH) is low (i.e., below ~40% RH). In contrast, atmospheric water generators that utilise sorbents enable capture of vapour at low RH conditions and can be driven by the abundant source of solar-thermal energy with higher efficiency. Here, we demonstrate an air-cooled sorbent-based atmospheric water harvesting device using the metal-organic framework (MOF)-801 [Zr 6 O 4 (OH) 4 (fumarate) 6 ] operating in an exceptionally arid climate (10-40% RH) and sub-zero dew points (Tempe, Arizona, USA) with a thermal efficiency (solar input to water conversion) of ~14%. We predict that this device delivered over 0.25 L of water per kg of MOF for a single daily cycle.

We describe a 2d analog of the Jordan-Wigner transformation which maps an arbitrary fermionic system on a 2d lattice to a lattice gauge theory while preserving the locality of the Hamiltonian. When the space is simply-connected, this bosonization map is an equivalence. We describe several examples of 2d bosonization, including free fermions on square and honeycomb lattices and the Hubbard model. We describe Euclidean actions for the corresponding lattice gauge theories and find that they contains Chern-Simons-like terms. Finally, we write down a fermionic dual of the gauged Ising model (the Fradkin-Shenker model)., Comment: 30 pages, 8 figures

$SU(N)$ gauge theory is time reversal invariant at $\theta=0$ and $\theta=\pi$. We show that at $\theta=\pi$ there is a discrete 't Hooft anomaly involving time reversal and the center symmetry. This anomaly leads to constraints on the vacua of the theory. It follows that at $\theta=\pi$ the vacuum cannot be a trivial non-degenerate gapped state. (By contrast, the vacuum at $\theta=0$ is gapped, non-degenerate, and trivial.) Due to the anomaly, the theory admits nontrivial domain walls supporting lower-dimensional theories. Depending on the nature of the vacuum at $\theta=\pi$, several phase diagrams are possible. Assuming area law for space-like loops, one arrives at an inequality involving the temperatures at which CP and the center symmetry are restored. We also analyze alternative scenarios for $SU(2)$ gauge theory. The underlying symmetry at $\theta=\pi$ is the dihedral group of 8 elements. If deconfined loops are allowed, one can have two $O(2)$-symmetric fixed points. It may also be that the four-dimensional theory around $\theta=\pi$ is gapless, e.g. a Coulomb phase could match the underlying anomalies., Comment: 62 pages, 9 figures, important typos fixed, added comments

We discuss bosonization and Fermionic Short-Range-Entangled (FSRE) phases of matter in one, two, and three spatial dimensions, emphasizing the physical meaning of the cohomological parameters which label such phases and the connection with higher-form symmetries. We propose a classification scheme for fermionic SPT phases in three spatial dimensions with an arbitrary finite point symmetry G. It generalizes the supercohomology of Gu and Wen. We argue that the most general such phase can be obtained from a bosonic "shadow" by condensing both fermionic particles and strings., Comment: 47 pages