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Objective In the hydrogen purification system, in order to analyze the process energy, the influence of oxygen mole fraction in feedstock on heat release from hydrogen-oxygen reaction and reactor temperature was investigated. Method The energy consumption of the electric heater and the amount of cold consumed by the cooler were further calculated by the method of model calculation to enable the optimization of the process flow. Based on this, a new purification process of heat exchange regeneration gas was proposed, and the effects of oxygen mole fraction and logistics flow on system temperature were analyzed. Results The heating can meet the energy requirements only when the oxygen mole fraction is above 0.13%. Compared with the original process, the new heat exchange regeneration gas purification process can save more than 88% of the cooling capacity, and the operating temperature of the system can be maintained without electric heating. Conclusion The new heat exchange regeneration gas purification process can fully use the heat released by the hydrogen and oxygen reaction to heat the cold flow, save the electricity energy consumption and cooling capacity, and reduce operating costs. [ABSTRACT FROM AUTHOR]

Materials processing with ultrashort laser pulses is one of the most important approaches when it comes to machining with very high accuracy. High pulse repetition rates and high average laser power can be used to attain high productivity. By tightly focusing the laser beam, the irradiances on the workpiece can exceed 1013 W/cm2, and thus cause usually unwanted X-ray emission. Pulsed laser processing of micro holes exhibits two typical features: a gradual increase in the irradiated surface within the hole and, with this, a decrease in the local irradiance. This and the shielding by the surrounding material diminishes the amount of ionizing radiation emitted from the process; therefore, both effects lead to a reduction in the potential X-ray exposure of an operator or any nearby person. The present study was performed to quantify this self-shielding of the X-ray emission from laser-drilled micro holes. Percussion drilling in standard air atmosphere was investigated using a laser with a wavelength of 800 nm a pulse duration of 1 ps, a repetition rate of 1 kHz, and with irradiances of up to 1.1·1014 W/cm. The X-ray emission was measured by means of a spectrometer. In addition to the experimental results, we present a model to predict the expected X-ray emission at different angles to the surface. These calculations are based on raytracing simulations to obtain the local irradiance, from which the local X-ray emission inside the holes can be calculated. It was found that the X-ray exposure measured in the surroundings strongly depends on the geometry of the hole and the measuring direction, as predicted by the theoretical model. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Ground Improvement is the property of Journal of Ground Improvement Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Internal waves based on measurements on cruise 87 of the R/V Akademik Mstislav Keldysh in the Bransfield Strait near Half Moon Island and calculations using a numerical model are analyzed. The measurements were carried out on January 25, 2022 over 4 h using a line of temperature and pressure sensors along with CTD probe measurements. Temperature fluctuations based on the data from these sensors showed that the amplitude of internal waves was close to 5 m, sometimes reaching 15 m. Irregular semidiurnal tides predominate in the study area based on the calculation results using the TPXO9 global tidal model. Numerical calculations of the internal wave parameters show that the baroclinic tide generated on a steep slope breaks up into higher frequency waves. [ABSTRACT FROM AUTHOR]

We have established that relatively simple calculations of the Coulomb interaction in the lattice of doped lithium niobate (LN, LiNbO3) can confirm the physical properties of real crystals. We have developed a method for the double adjustment of real XRD data for calculations of Coulomb interaction in a LN cluster. The study considers two crystals doped with boron (LN:B); LN:B(1) has been grown from a charge with 0.02 mol% B2O3, boron has been introduced by homogeneous doping, LN:B(2) has been grown from a charge with 0.547 mol% B2O3, and boron has been introduced by direct solid-state doping. XRD and Rietveld method data have been obtained for these crystals. The obtained data have been used to build a model of the LN cluster; the cluster in the calculations consists of six oxygen octahedra of the LN structure. The cluster configuration has been chosen in such a way that the structure contains two tetrahedral voids. We have studied 10 variants of filling a cluster with intrinsic cations (Li, Nb), defects, and vacancies. There are 10 of them because, in addition to the basic cations in their positions, defects are present in the structure. In terms of the defects used (NbLi, NbV), we have used only those that Rietveld found for these exact LN:B crystals, and the vacancy in the niobium octahedron (VNb) compensates for these defects, according to the models known for LN. The energy of the Coulomb interaction between the cluster structure of a real crystal and the boron cation localized in it in different positions has been calculated for each of the configurations. Calculations have demonstrated that B is more likely to be embedded near a defect than in a regular structure. This means that boron positively influences the local substructure of doped LN crystals, not only structures the melt during crystal growth. Calculations have shown that the type and location of structural defects affect the position of boron in the structure of a LN crystal. Calculations have also shown that LN:B(1) has a more stable structure, including optical damage resistance. The photoinduced light scattering (PILS) patterns and conoscopic patterns confirm this conclusion for the studied LN:B crystals. The information obtained in this study may be useful for interpreting the defective structure of LN crystals co-doped with boron and metals (Mg, Zn, etc.). This will supplement the knowledge available in the literature regarding models that describe the structure of complexly doped LN crystals. [ABSTRACT FROM AUTHOR]

Relevance. The extraction of natural and associated petroleum gases is accompanied by the necessary gas preparation for delivery to the consumer for commercial use. In particular, in gas and oil fields, the separation of all side homologues of methane, moisture and other non-hydrocarbon compounds that are part of associated petroleum gases, which worsen the operating conditions of equipment and lower the quality of the feedstock, are used. With the ever-increasing degree of water cut in gas and oil fields, it is necessary to progressively develop technological methods for gas treatment, including one of the most common in the Russian Federation – the absorption method of drying natural and associated petroleum gases from water impurities. Purpose: to substantiate the use of diethylene glycol in preparation of natural gas, as the most effective absorbent in the Far North. Object: complex natural gas treatment unit. Method. The calculation of the model of the complex gas treatment unit was carried out in the UniSim Design R470 software package. Results. The influence of the main technological parameters: temperature, pressure of absorption drying of natural gas on the absorbent diethylene glycol at the gas treatment plant for the removal of water impurities is investigated. The optimal pressure and temperature conditions for effective removal of moisture from natural gas by the method of water absorption by diethylene glycol at high pressure of the input raw material are determined. It is shown that the use of diethylene glycol absorbent is most effective in the conditions of the Far North. When diethylene glycol is used as an absorbent for drying natural gas from water at low temperatures, the energy consumption for gas compression, its cooling in front of the absorber, and the consumption of the dryer are significantly reduced compared to other absorbents. The most effective technological parameters of the operation of an absorption plant for drying natural gas at a diethylenglykol concentration of 98 % wt. and raw natural gas consumption of 385 thousand m³/h were determined. Diethylenglykol already at a contact temperature of 19 °C dries the gas to the regulated dew point temperature of minus 20 °C and pressure in the gas treatment unit of at least 4 MPa and above. On the contrary, exceeding the gas–diethylenglykol contact temperature above 20 °С and lowering the pressure below 4 MPa lead to a significant increase in energy consumption, the entrainment of the diethylene glycol absorbent and the deterioration of the economic indicators of the natural gas drying from water impurities.

The risk of algal blooms in landscape water bodies replenished by reclaimed water (RW) prompted the scientific management of RW discharge issues. Mathematical models are concise and convincing methods to stimulate algal growth and calculate thresholds for water quality control. This study presented three types of models, including one-parameter models, multiple-parameter models, and ecosystem dynamic models. Key influencing factors (such as nutrient concentration, light intensity, temperature, biotic processes, specific hydraulic conditions, etc.) are taken into consideration in these models. The work provided feasible methods for the management of reclaimed water to prevent water bloom outbreaks.

Copyright of Gazdalkodas is the property of Herman Otto Intezet Nonprofit Kft. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The steady 3-D raw water turbulent flow is numerically investigated. This flow is formed of solid silica sand (quartz) carried by water in stainless steel pipe. The flow in a straight pipe and flow in a pipe with a sudden contraction are analyzed using a two-way coupled Eulerian-Lagrangian approach. Erosion rate is estimated by Oka erosion model combined with the constant coefficient of restitution. The effect of solid particles mass flow rate, inlet velocity, particle diameter, internal pipe diameter, orientation, contraction coefficient, and wall pipe contraction angle on erosion rate are examined. The predicted erosion is distributed homogenously for straight pipe, while the step wall area of the contraction is the most eroded part. The erosion rate increases with the increase of solid particles diameter, flow rate, inlet velocity, and decreasing pipe diameter. Iit is found that the erosion is limited till the particle diameter reaches 500 µm then it starts to increase. The erosion rate increases with decreasing contraction coefficient and step wall angle. When the step wall angle decreased to 300, the erosion rate is reduced by 30 times that for 900. So, decreasing step wall angle can be considered as a geometrical solution to reduce erosion rate.

Human activities incur soil heavy metal pollution that will manifest migration between the two phases of water and soil, which poses grave threat to human healthy. Research of the heavy metal phase migration in urban reservoir projects, with the focus of its leaching characteristics, is therefore highly significant. Through the investigation of soil background value, extraction kinetics, water quality risk assessment, statistical analysis and theoretical model simulation, the leaching characteristics of soil heavy metals were explored and the safety of water quality was evaluated. The results show that under the simulated extreme extraction conditions, except that nickel slightly exceeded the standard limit of drinking water, the heavy metals of copper, zinc, cadmium, lead, mercury and arsenic are at the pollution-free level, and the water quality is relatively safe. In the model calculation simulating the actual operation of the reservoir, the leaching concentration of each heavy metal is far lower than the class II water standard limit in the Hygienic Standard for Drinking Water (GB 5749—2022) and the Environmental Quality Standard for Surface Water (GB 3838—2002), indicating that the water quality of the reservoir can meet the requirements of safe water supply in the actual operation. [ABSTRACT FROM AUTHOR]

We synthesize siloxane-urethane copolymer aqueous dispersions by using hydroxypropyl terminated polydimethysiloxane (HAS) and hydrohxypolyester terminated polydimethylsiloxane (PES) as siloxane monomers and dimethylol propionic acid (DMPA) as intrachain emulsifier. The stable dispersions have the average sizes from 24 to 59 nm dependent on the reaction conditions. From the dispersions, the transparent films with the improved hydrophobicity are prepared. The water contacting angels of these films are enhanced by increasing the siloxane contents. In order to reveal the influences of the different chemical structures of siloxane, these films are also investigated about the UV-vis spectrum, tensile property, topography, and glass transition. It is obtained that the use of PES can obtain the films with better light transmission, around 95%. It is observed by atom force microscope that the as-synthesized siloxane-urethane copolymer films display less phase separation, agreeing well with the high transparency. Moreover, the rheological tests and model calculations are carried out to illustrate the effects of DMPA concentrations on the viscosities and correlation to the dispersion particle sizes. The as-synthesized aqueous nanodispersions promise to be used for the transparent coatings of hydrophobicity. [ABSTRACT FROM AUTHOR]

Diffusion flux is an essential tool to estimate the contribution of internal nitrogen and phosphorus in eutrophic lakes. There are mainly two methods, i.e., model calculation based on in-situ porewater sampling and water quality monitoring in laboratory incubation. The results obtained by the two methods are rarely compared, decreasing the validity of internal contribution and following management strategies. In this study, sediment samples were collected from a lake in China, then the fluxes were estimated by model calculation and laboratory incubation. The results show that there is an order of magnitude difference in the fluxes measured by these two methods. The mean values of ammonia (NH4+-N) and soluble reactive phosphate (SRP) obtained from the model calculations were 24.4 and 1.30, respectively. The mean values of NH4+-N and SRP obtained in the undisturbed group of sediment incubation were 7.84 and 5.47, respectively, and in the disturbed group of sediment incubation were 16.2 and 4.06, respectively. Sediment incubation is a combination of multiple influencing factors to obtain fluxes, while porewater model is based on molecular diffusion as the theoretical basis for obtaining fluxes. According to the different approaches of the two methods, sediment incubation is recommended as a research tool in lake autochthonous release management when the main objective is to remove pollution, while the porewater model is recommended as a research tool when the main objective is to control pollution. When assessing the diffusive flux of nitrogen, it is recommended to choose the stable form of total dissolved nitrogen to discuss the flux results. [ABSTRACT FROM AUTHOR]

Investing labor time in herbage measurements is important for precision pasture management. In this study, the labor input of three smart herbage measurement tools—multispectral imagery linked to an unmanned aerial vehicle (UAV), a semi-automated rising plate meter (RPM), and near-infrared reflectance spectroscopy (NIRS) of cut herbage samples—and of direct observation was modeled based on the REFA work element method. Three to five users were observed during work execution to identify best-practice workflows. Time measurements were conducted using video footage. The resulting standard times of work elements were used to model labor input for herbage measurements in different farm sizes (i.e., milking platforms of 6–100 ha) and subdivisions of a farm's milking platform (i.e., 4–45 paddocks). Labor time requirement differed between the smart farming tools (0.7–5.9 h) depending on the farm size and milking platform scenario. The labor time requirement increased for all tools with an increase in farm size and was lowest for the RPM. For the UAV tool, it did not increase noticeably when the division of the milking platform changed. Nevertheless, the potential to save time was identified for the UAV and the NIRS. Therefore, the automation of certain steps in the workflows would contribute to sociotechnological sustainable pasture management. [ABSTRACT FROM AUTHOR]

Excited states have been observed for the first time in the very neutron-deficient odd-odd nucleus 57 120 La 63. The observed γ rays have been assigned based on coincidences with lanthanum X rays measured with the JUROGAM 3 array and with A = 120 fusion-evaporation residues measured with the MARA separator. The observed γ rays form a rotational band which decays to the ground state via a cascade of four low-energy transitions. Based on the systematic comparisons with the heavier odd-odd La isotopes we assign spin-parity 4 + to the ground state and a π h 11 / 2 ⊗ ν h 11 / 2 configuration to the rotational band. The nuclear shape has been investigated by the cranked Nilsson-Strutinsky model. Two quasiparticle plus triaxial rotor model calculations including the np interaction nicely reproduce the spin of the inversion between the even- and odd-spin cascades of E 2 transitions, giving credit to the np interaction as an important parameter responsible for the mechanism inducing the inversion. The position of the Fermi levels, in particular for neutrons, also has a strong impact on the observed inversion in the chain of lanthanum nuclei. [ABSTRACT FROM AUTHOR]

Two rotational bands are identified in 119 Cs, one of which having very similar pattern to that of the strongly-coupled π g 9 / 2 [ 404 ] 9 / 2 + band. The properties of the bands with similar patterns extracted from the experimental data are in agreement with a chiral interpretation. Tilted axis cranking covariant density functional theory with pairing correlations and particle-number conserving cranked shell model calculations are employed to determine the deformation and to investigate the band configurations, respectively. It results that the backbending is induced by the rotational alignment of two h 11 / 2 protons, whose angular momenta reorient from the short to the intermediate axis, in a plane orthogonal to the angular momentum of the strongly-coupled g 9 / 2 proton which keeps aligned along the long axis. The total spin points in 3D, inducing the breaking of the chiral symmetry. This is the first observation of candidate chiral bands built on a configuration with three protons, one in the strongly coupled [ 404 ] 9 / 2 + orbital which does not change orientation with increasing rotational frequency, and two in the h 11 / 2 orbital which reorients to the rotation axis. The bands are observed in the transient backbending regime, showing that the chirality in nuclei is a general phenomenon, being robust and present not only in nuclei with nearly maximal triaxiality and pure configurations, but also in nuclei with moderate triaxiality and mixed configurations which gradually evolve from one to three-quasiparticle configurations, like in the backbending region. [ABSTRACT FROM AUTHOR]

Long-distance pipeline is buried in the ordinary section, and for the pipeline passing through the seasonal frost area with slope, additional stress is applied due to the slope creep caused by freezing and thawing. The axial stress change of pipeline resulted from the slope creep can be monitored by the axial strain sensors installed along the pipeline. However, for the strength evaluation of pipeline, the initial stress of pipeline strain monitoring should be clear. For the stress detection technology mostly used in laboratory environment is not mature in engineering, the initial stress of pipeline strain monitoring can only be obtained by the calculation method of finite element modeling. Taking the buried section of Sebei-Xining-Lanzhou Pipeline I crossing the seasonal slope frost area as an example, the current major risks of pipeline in the seasonal frost area, distribution and determination of soil displacement, and the stress and deformation of the pipeline in seasonal frost area due to slope creep were introduced. By using the Vector Form Intrinsic Finite Element (VFIFE) method, the numerical simulation of pipeline at hazard point was conducted with space beam element and nonlinear soil spring model, and the stress distribution of the pipeline was obtained, which provides basis for determination of the cross-sectional location of strain monitoring, estimate of current stress distribution and safety assessment of pipeline.

The precession of an atomic nucleus can be approximately described as wobbling motion, arising from the coupling of a rotation and a harmonic vibration. Recently, a number of wobbling bands were reported at low spin, which violate the wobbling approximation that can be valid only at high spin. In the present work, we explore the nature of the reported low-spin wobbling bands. Via a new experiment including both angular correlation and linear polarization measurements, we demonstrate that one such band in 187Au is generated by dominant single-particle excitation rather than by the excitation of a wobbling phonon. Assessing the experimental proofs and discussions to assign the reported low-spin wobbling bands, we further point out that the imperfect research paradigm used previously would lead to unreliable identification of low-spin wobbling bands.

The steady 3-D raw water turbulent flow is numerically investigated. This flow is formed of solid silica sand (quartz) carried by water in stainless steel pipe. The flow in a straight pipe and flow in a pipe with a sudden contraction are analyzed using a two-way coupled Eulerian-Lagrangian approach. Erosion rate is estimated by Oka erosion model combined with the constant coefficient of restitution. The effect of solid particles mass flow rate, inlet velocity, particle diameter, internal pipe diameter, orientation, contraction coefficient, and wall pipe contraction angle on erosion rate are examined. The predicted erosion is distributed homogenously for straight pipe, while the step wall area of the contraction is the most eroded part. The erosion rate increases with the increase of solid particles diameter, flow rate, inlet velocity, and decreasing pipe diameter. Iit is found that the erosion is limited till the particle diameter reaches 500 μm then it starts to increase. The erosion rate increases with decreasing contraction coefficient and step wall angle. When the step wall angle decreased to 300, the erosion rate is reduced by 30 times that for 900. So, decreasing step wall angle can be considered as a geometrical solution to reduce erosion rate. [ABSTRACT FROM AUTHOR]

The structure of casein micelles has been extensively studied over several decades, and a variety of models have been proposed to depict the structure of bovine casein micelles. However, the exact structure of casein micelles remains unclear. The interpretation of small-angle X-ray scattering (SAXS) profiles in relation to the internal structure of the casein micelle is also an ongoing debate. In this study, a structural model of a casein micelle for SAXS measurements was reconsidered by comparing experimentally obtained SAXS profiles with the theoretically calculated curves using various structural models, including the liquid-like submicelle model, aggregate model composed of submicelles, simple nanocluster model in which colloidal calcium phosphate (CCP) randomly disperses in a micelle, the structural model with water channels, and the structural model with water domains. In addition, the micelle model with hard regions proposed by Bouchoux et al. (Biophys. J. 99, 3754-3762) was also revisited. This hard region model was improved to the water domain model by changing interpretation of the calculated model. The results show that all the SAXS profiles calculated based on our models, except for the simple nanocluster model, could reproduce features of the experimental profile. However, comparing the parameters obtained by fitting revealed that the structural model with water domains was the most reasonable. [ABSTRACT FROM AUTHOR]

As an acoustic metamaterial, Metal–organic frameworks (MOFs) can absorb sound energy abnormally. In this research, a thin and flexible acoustic material was prepared by growing MOF on the fabric. The successful growth of MIL-53(Fe) on the fiber surface was confirmed by SEM, FTIR, XRD and XPS. From the sound absorption and sound insulation test results of MIL-53(Fe)@fabric, the in-situ growth of MIL-53(Fe) greatly improves the sound absorption and sound insulation performance of the fabric, and gives the fabric an abnormal acoustic effect. From the calculation results of the theoretical model, the growth of the sub-wavelength scale MIL-53(Fe) significantly increases the flow resistance of the fabric, which is the root cause of the abnormal sound absorption of the material. It is worth noting that the sound transmission loss of the prepared flexible material doesn't follow the mass law and exhibits excellent sound insulation performance. This is not only related to the increase in the sound energy reflected by the fabric, but also to the abnormal sound absorption of MIL-53(Fe). Here, the sound insulation performance of MOFs@fabric is reported for the first time. This work promotes the research and application of MOFs in the field of acoustics, and provides a method and theoretical basis for the design and preparation of acoustic protection textiles. [ABSTRACT FROM AUTHOR]

Prolate-oblate shape coexistence close to the ground state in the strongly-deformed proton-rich A≈120 nuclei is reported for the first time. One of the four reported bands in 119Cs, built on a 11/2− state at 670 keV, consists of nearly degenerate signature partners, and has properties which unequivocally indicate the strongly-coupled πh11/2[505]11/2− configuration associated with oblate shape. Together with the decoupled πh11/2[541]3/2− band built on the 11/2− prolate state at 110 keV, for which a half-life of T1/2=55(5)μs has been measured, the new bands bring evidence of shape coexistence at low spin in the proton-rich strongly deformed A≈120 nuclei, a phenomenon predicted since long time, but not yet observed. Calculations using the particle-number conserving cranked shell model and two dimensional tilted axis cranking covariant density functional theory support and well reproduce the observed oblate and prolate coexisting low-energy states in 119Cs.

Abstract A simple steady state model of potentiometric stripping analysis and its derivative mode that are influenced by the film of adsorbed substance that hinders the diffusion of oxidant and metal ions is developed. The dependence of stripping time and the maximum in the derivative mode on the degree of inhibition is calculated. The responses are enhanced if the flux of oxidant is diminished.

Copyright of Gazdalkodas is the property of Herman Otto Intezet Nonprofit Kft. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

• The synthesized catalyst performed good stability during syngas production. • Nickel-cobalt alloy structure was formed, thus increasing the catalyst stability. • Model calculation revealed the promotion effect of lanthanum carbonate. • The Langmuir-Hinshewood reaction mechanism was suitable for the optimized catalyst. With high surface area (1393 m2/g) and fibrous structure, carbon fiber (CF) was used to prepare a composite of CF-lanthanum oxide (La 2 O 3), which was applied as support to synthesize nickel-cobalt based bimetallic catalyst. The as-prepared catalysts were utilized in CO 2 reforming of methane and it performed well at the metal ratio (nickel to cobalt) of 4:1 with an ideal syngas (H 2 /CO reached to 1.1) produced. The characterization results showed that La 2 O 3 uniformly grew on the surface of carbon fiber in wrinkled like. Moreover, nickel-cobalt alloy structures were formed on the surface of 4Ni-1Co/CF-La 2 O 3 catalyst, thus improving the resistance to Ni-sintering, then promoting the stability of syngas production. Except for the promotion effect of cobalt, the role of La 2 O 3 addition was also demonstrated by model calculation. It was found that the lanthanum carbonate (La 2 O 2 CO 3) formed during CO 2 adsorption process. The formation of the intermediate could facilitate to the CO 2 dissociation by decreasing the CO 2 activation energy, thus promoting the CO 2 conversion to produce more CO. Combined with the kinetic experimental results, the reaction mechanism over 4Ni-1Co/CF-La 2 O 3 was proposed with the reactants of CH 4 and CO 2 dissociated both on the surface of the support and the metal active sites. It was corresponded to the Langmuir-Hinshewood mechanism type. [ABSTRACT FROM AUTHOR]

Copyright of Gazdalkodas is the property of Herman Otto Intezet Nonprofit Kft. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

• Research on the solid-liquid phase of diprophylline in pure and binary solvents. • The solubility data were correlated by some thermodynamic models. • Discuss the effect of solvent properties on the dissolution process. • Some thermodynamic properties of dissolution process are evaluated. Co-solvent plays an important role in drug crystallization. More importantly, the change of temperature and the addition of co-solvent can make the operation of crystallization purification more controllable. In this work, the solubility of diprophylline in methanol, ethanol, n -propanol, iso propanol, acetone, acetonitrile, ethyl acetate, 1,4-dioxane, water, toluene and mixture of (methanol + water) was experimentally determined at T = 283.15–323.15 K. The solubility data obtained experimentally in all studied pure solvents followed the sequence: water > 1,4-dioxane > methanol > acetonitrile > iso propanol > ethanol > n -propanol > ethyl acetate > toluene > acetone. In addition, in mixture of (methanol + water) the solubility increases at first and then decreases with the increasing mass fraction of methanol. The composition dependence of the solubility has a maximum around (methanol mass fraction) w = 0.4 at all investigated temperatures. Moreover, the effect of solvent properties on solubility is briefly discussed. The modified Apelblat equation, λh equation, Jouyban-Acree model and CNIBS/R-K model are applied to correlate the solubility. All the values of RAD and RMSD are no more than 5.34 × 10−2 and 5.83 × 10−4, respectively. Apparent thermodynamic analysis indicates that the dissolution is an endothermic and entropy driven process. [ABSTRACT FROM AUTHOR]

On 12 May 2008, a devastating mega-earthquake of magnitude 8.0 struck the Wenchuan area, northwestern Sichuan Province, China. Following this earthquake event, many areas in the affected areas were susceptible to geological disasters, such as debris flows, landslides and other secondary disasters. To better understand the mechanism of the formation processes of geological disasters, and to reduce the economic loss caused by the disasters, a comprehensive analysis is required. With the aim of obtaining the characteristics of unfavourable geological bodies, and analysing their stability, we choose the Gengda Township as an example (there are many unfavourable geological bodies distributed in this area, including landslides and deformation bodies). Field investigations and computational models are employed to analyse the stability of the unfavourable geological bodies. Through preliminary analysis and model calculation, the following conclusions can be drawn: under natural conditions, the stability factor of the landslide ranges from about 1.02–1.03, which means that the landslide is in a basically stable or less stable condition. Under the effect of continuous heavy rainfall, the stability factor of the landslide will be significantly reduced, and the corresponding value ranges from 0.9–0.96, which signifies that the landslide is in an unstable condition. For No 1 and No 2 deformation bodies (named by local inhabitants), the stability varied from less stable to unstable, and basically stable to unstable, respectively. On the basis of the results of the calculation, some countermeasures are proposed to mitigate the effects of these disasters probably caused by geological bodies. [ABSTRACT FROM AUTHOR]

The dynamic characteristics of debris flow play crucial roles in disaster prevention and mitigation. However, due to the complexity of the formation processes, monitoring the corresponding features is time-consuming and tedious work. With the aim of acquiring accurate parameters with regard to debris flow in Bajiao gully, a detailed field investigation was conducted, and the fundamental data closely related with debris flow initiation could be obtained. In combination with remote sensing interpretation, the distribution of the loose solid material in the study area was determined, and the total volume was calculated. On the basis of these data, a preliminary analysis with regard to the occurrence of debris flow was performed, from which the following conclusions could be drawn: the debris flow in Bajiao gully can be classified into dilute debris flow, and the occurrence frequency is low. To better provide useful information for designing engineering measures, some models were employed to calculate the dynamic characteristics of the debris flow, including unit weight, debris flow velocity, debris flow discharge, and the total amount of debris flow at a certain time, and the corresponding data were identified. Therefore, combined with the topography and meteorological conditions in this area, comprehensive prevention measures can be proposed, which can greatly reduce the risk caused by the debris flow in Bajiao gully watershed, and benefit both local economic development and the safety of transportation. [ABSTRACT FROM AUTHOR]

Highlights • Production cross-sections of 59Co(α,2n)61Cu, 58Ni(α,p)61Cu, 60Ni(d,n)61Cu and 64Zn(p,α)61Cu are selected for evaluation. • Data were renormalized based on the latest decay data and monitor reactions. • SOK code combined with least-squares method was applied to the corrected data. • Evaluated data with covariance matrix are generated and report herein. • The various production routes of 61Cu were compared, and recommended excitation functions were derived. Abstract Production cross-sections of 61Cu, a promising radionuclide for PET imaging applications, were evaluated for the light-ion-induced nuclear reactions on Co, Ni, Zn targets. Simultaneous Evaluation on KALMAN (SOK) code combined with least squares concept was used to obtain the evaluated data together with covariances. The various production routes of 61Cu were compared, and recommended excitation functions were derived using a well-defined statistical procedure. The evaluated data were also compared with the predictions of the nuclear reaction model codes TALYS and EMPIRE, and found a partial agreement among them. This study indicates that the 60Ni(d,n)61Cu reaction is the method of choice for 61Cu production; however, the 58Ni(α,p)61Cu and 59Co(α,2n)61Cu reactions also appears to have great potential. [ABSTRACT FROM AUTHOR]

Highlights • Alpha induced nuclear reactions on natural silver in the 40–50 MeV region. • Stacked foil irradiation technique. • Comparison with the EMPIRE 3.2 and TENDL-2017 calculations. • Physical yield. • Thin Layer Activation. Abstract Natural silver targets have been irradiated by using a 50 MeV alpha-particle beam in order to measure the activation cross sections of radioisotopes in the 40–50 MeV energy range. Among the radio-products there are medically important isotopes such as 110mIn and 111In. For optimizing the production of these radioisotopes and regarding their purity and specific activity the cross section data for every produced radioisotope are important. New data are measured in this energy range and the results of some previous measurements have been confirmed. Physical yield curves have been calculated by using the new cross section data completed with the results from the literature. [ABSTRACT FROM AUTHOR]

With the newly proposed Global Ocean Observing Integration, ocean observing scope has been expanded from the region to the global, therefore the need of large-scale ocean observing system integration has become more and more urgent. Currently, ocean observing systems enabled ocean sensor networks are commonly developed by different organizations using specific technologies and platforms, which brings several challenges in ocean observing instrument (OOI) access and ocean observing system seamless integration. Furthermore, the development of ocean observing systems often suffers from low efficiency due to the complex programming and debugging process. To solve these problems, a novel model, Complex Virtual Instrument (CVI) Model, is proposed. The model provides formal definitions on observing instrument description file, CVI description file, model calculation method, development model and interaction standard. In addition, this model establishes mathematical expressions of two model calculation operations, meanwhile builds the mapping relationship between observing instrument description file and CVI description file. The CVI based on the new model can achieve automatic access to different OOIs, seamless integration and communication for heterogeneous environments, and further implement standardized data access and management for the global unified ocean observing network. Throughout the development, integration and application of such CVI, the rationality and feasibility of the model have been evaluated. The results confirm that the proposed model can effectively implement heterogeneous system integration, improve development efficiency, make full usage of reusable components, reduce development cost, and enhance overall software system quality. We believe that our new model has great significance to promote the large-scale ocean observing system integration. [ABSTRACT FROM AUTHOR]

Film stretch was incorporated in the enthalpy relaxation experiment in order to examine physical ageing response of polystyrene subjected to large deformation. It was stretched in the midst of ageing step, where ageing temperature was located slightly higher than the onset of the glass transition shoulder to minimise the stretching effect on the enthalpy decay, and then heat capacity, c p ( T ), versus temperature curve was acquired by DSC (differential scanning calorimetry) as functions of the ageing time and stretch ratio. Pre-hold and post-hold stretches are both carried out, those are stretching-and-ageing and ageing-and-stretching, respectively. As a result, the stretching effect appeared as the shift of glass transition shoulder in c p ( T ) curve; its onset temperature increased with the increase in the stretch ratio. A remarkable discrepancy for the shift of glass transition shoulder was observed between the samples of pre-hold and post-hold stretches. The experimental c p ( T ) was reproduced by the modelling data calculated on the basis of Tool-Narayanaswamy-Moynihan framework to derive the data of fictive temperature ( T f ). It was revealed that T f isothermally increases with stretching. The amount of T f increase depends on both the ageing time and stretch ratio. The discrepancy of the shift amount appeared between pre-hold and post-hold stretches was interpreted in terms of the increase in T f . [ABSTRACT FROM AUTHOR]

Based on the elastic theory of transient flow, the motion equation and continuity equation of the transient flow are established, and the transient flow model of long-distance pipeline is derived. This paper lays a solid theoretical foundation for the further study of the small leakage of long-distance pipeline. [ABSTRACT FROM AUTHOR]

The appearances of significant efflux of carbon dioxide through soil surfaces is a frequent natural phenomena in the wider vicinity of relatively young volcanic fields. These mofettes are often utilised as dry carbon dioxide spas to treat patients suffering from cardiovascular diseases. The carbon dioxide always carries some naturally occurring radioactive radon gas with it. On the one hand this radon gas might pose some radiation risk for the patients and staff of such carbon dioxide spas, on the other hand it may be used as a natural tracer for the study of transport of its carrier gas in the subsurface and in the pools. In this work we have measured the spatial variation of radon activity concentration in the gas phase of the carbon dioxide gas pool of the Cardiology Hospital and in the gas and water phases of the Hell-Mud, which is a wet open pit mofette in the city of Covasna. We have developed a hydro- and gas-geological conceptual and mathematical model with which we were able to describe the measured spatial and temporal behaviour of radon gas concentration. We have found that the relatively low radon concentrations at the bottom of these pools can be explained by removing the radon content of water by intense bubbling degassing of the oversaturated carbonated waters. • Radon was used as natural tracer of transport and degassing of deep origin CO 2 in the gas and water phases of mofettes. • The chosen advection – eddy diffusion model describes relatively well the measurement results in the airspace of mofettes. • Groundwater discharge rate and wind speed are the main driving factors in determining radon levels in Hell-Mud. [ABSTRACT FROM AUTHOR]

Crystalline (including multicrystalline) silicon based devices dominate the present solar cell industry due to their durability, relatively low cost, and the vast silicon knowledge base developed by the microelectronics industry. Multicrystalline silicon is the becoming dominating substrate material of the photovoltaic cells. This is obviously due to the significant cost savings compared with the single crystalline silicon wafers. Consequently, the conversion efficiency of the mc-Si solar cell is suffering because of the low cost requirement of the starting materials. One contributor to the lower performance of the mc-Si cells is the grain boundaries which reduce the charge carrier collection properties. Thus, reducing solar cell fabricate is an attractive way to reduce material costs. However, the model calculations in the presented paper show that the rear surface recombination velocity (S) in multicrystalline silicon cell is greater than (mc-Si) cell and the efficiency of mc-Si cell is lower than the efficiency of a crystalline cell. [ABSTRACT FROM AUTHOR]

Excitation functions of 3 He-particle induced nuclear reactions on natural palladium were measured using the standard stacked foil technique and high resolution γ-ray spectroscopy. From their threshold energies up to 27 MeV, cross-sections for nat Pd( 3 He,x) 103,104,105,106m,110m,111,112 Ag and nat Pd( 3 He,x) 104,105,107,111m Cd reactions were measured. The nuclear model codes TALYS-1.4, and EMPIRE-3.1 were used to describe the formation of these products. The present data were compared to theoretical results and to the available experimental data. Integral yields for some important radioisotopes were determined. [ABSTRACT FROM AUTHOR]

A novel statistical model for the cooperative binding of monomeric ligands to a linear lattice is developed to study the interaction of ionic surfactant molecules with flexible polyion chain in dilute solution. Electrostatic binding of a ligand to a site on the polyion and hydrophobic associations between the neighboring bound ligands are assumed to be stochastic processes. Ligand association separated by several lattice points within defined width is introduced for the flexible polyion. Model calculations by the Monte Carlo method are carried out to investigate the binding behavior. The hypothesis on the ligand association and its width on the chain are of importance in determining critical aggregation concentration and binding isotherm. The results are reasonable for the interpretations of several surfactant-flexible polyion binding experiments. The implications of the approach are presented and discussed. [ABSTRACT FROM AUTHOR]

The article suggests physical and mathematical models used in the design of vortex evaporation chambers for separating multicomponent media. [ABSTRACT FROM AUTHOR]