Values Of Initial Temperature Research Articles

Investigation of Magnetic Properties of Poly Vinyl Chloride Composites Prepared Using Different Ratios of Fe2O3 (Maghemite) Nanoparticles

Composites were prepared using polyvinyl chloride (PVC) and different percentages of Fe2O3 nanoparticles. All composites were characterized by FT-IR spectroscopy. Then, the thermal properties of the composites prepared in 1% and 10% ratios were examined. It was observed that the initial decomposition temperature (Ti) values of PVC composites prepared with Fe2O3 nanoparticles addition were lower than pure PVC. Magnetic properties of composites were examined with a vibrating sample magnetometer (VSM). The saturation magnetization values of PVC composites prepared by using 1% and 10% Fe2O3 were 2.77 and 7.06 emu / g, respectively.

Photoluminescence properties and energy transfer in the Sm3+ and Eu3+ co-doped Ca3Bi(PO4)3 red phosphor

Red phosphors play a vital role in improving the color quality and luminous efficiency of white light-emitting diodes (w-LED). However, it is still a challenge to develop red phosphors with higher efficiency, higher color purity, and better matching near-ultraviolet (n-UV) chips. In this paper, a series of Sm3+, Eu3+ co-doped Ca3Bi(PO4)3 (CBP) were successfully prepared by the high temperature solid-state reaction method. The crystal structure, photoluminescence properties, and energy transfer mechanism were investigated in detail. The maximum doping concentration of Eu3+ in CBP was confirmed to be 30 mol% in this research considering the structural instability with higher doping concentration. Under 393 nm n-UV excitation, CBP: 8 mol% Sm3+, 25 mol% Eu3+ phosphor exhibit excellent red-lighting emission at 612 nm with high color purity of 99.28 %. More impressively, the effective excitation wavelength of Sm3+, Eu3+ co-doped CBP phosphors is extended to 391–403 nm due to energy transfer from Sm3+ to Eu3+. Moreover, the energy transfer mechanism is rationalized through dipole–dipole interaction as indicated via decay kinetics studies. The fabricated w-LED emits white light, which has high color rendering index (CRI = 86.0) at color coordinate temperature CCT = 6985 K and luminous efficiency (66 lm/w). The phosphor shows excellent thermal stability, and the fluorescence intensity to temperature 423 K can retain 75.98 % of its initial value of room temperature. These results indicate that this phosphor with high-efficiency red-emitting is a promising candidate as a red component for n-UV LED application.

The effects of initial temperature and pressure on the mechanical properties of reinforced calcium phosphate cement with magnesium nanoparticles: A molecular dynamics approach

Reinforcing cement with nanoparticles is a way to reduce porosity and enhance the initial strength of cement. In this work, the calcium phosphate cement is reinforced with magnesium ion nanoparticles using the molecular dynamics simulation method. This work investigates the mechanical and thermal properties of simulated samples. In this approach, the ultimate strength, Young's modulus, and thermal stability are studied. The effects of different initial temperature values and pressures will be researched next. As the initial temperature increased from 300 to 400 K, the ultimate strength and Young's modulus decreased from 0.879 and 0.171 MPa to 0.843 and 0.154 MPa. Also, the thermal stability reduced from 1321 to 1294 K. This material has more strength at lower than higher temperatures. With increasing temperature, the materials become softer and lose their strength. As the initial temperature in the atomic samples increases, the mobility intensifies, and as a result, the stability of the structures decreases. Increasing the initial pressure from 1 to 5 bar, the ultimate strength and Young's modulus enhanced from 0.879 and 0.171 MPa to 0.889 and 0.178 MPa. Also, the thermal stability increased from 1321 K to 1371 K by increasing the initial pressure to 5 bar. As the pressure increases, the amplitude of the particle oscillation decreases. The nanoparticle-reinforced cement matrix shows more appropriate behavior in high-pressure environments. It is expected that the addition of Mg nanoparticles will increase the strength of calcium phosphate cement and be used for use in bone lesions.

Autoclave and pulsed ultrasound cavitation based thermal activation of persulfate for regeneration of hydrogen titanate nanotubes as recyclable dye adsorbent.

In the dye removal application, regeneration of hydrogen titanate nanotubes (HTN, H2Ti3O7) has been achieved via thermal activation of persulfate anion (PS, S2O82-) by using the conventional hot plate technique which has limitations from the commercial perspective since it does not provide any precise control over the thermal generation process typically during the scale-up operation. To overcome this drawback, HTN have been synthesized via hydrothermal process which exhibit the methylene blue (MB) adsorption of 93% at the initial dye concentration and solution pH of 90µM and 10 respectively. HTN have been regenerated via the thermal activation of PS by varying its initial concentration and regeneration temperature, within the range of 0.27-1 wt% and 40-80°C, under the thermal conditions set by the autoclave and pulsed ultrasound (US) cavitation process. The results of recycling experiments suggest that the optimum values of initial PS concentration and temperature, for the regeneration of HTN under the autoclave conditions, are 1 wt% and 70°C with the maximum MB adsorption of 92%, while, the corresponding values for the pulsed US cavitation process are 1 wt%, 80°C, and 91% respectively. Thus, the regeneration and recycling of HTN have been successfully demonstrated by using the autoclave and pulsed US cavitation process. Under the optimum conditions, MB degradation involves the generation and attack of SO4•- for both the thermal generation techniques. The regeneration techniques developed here may be utilized in future during the scale-up operation and also for the regeneration of adsorbents besides HTN.

Thermally Stable Piezoelectric Performance of MnO2 Inserted Pseudo-tetragonal Phase Existent CaBi2Nb2O9-based Ceramics

ABSTRACT Pseudo-tetragonal phase boundary existent Ca0.60(Li0.5Bi0.5)0.40Bi2Nb2O9:xwt%MnO2 (CBNL:xMn) ceramic series is fabricated to investigate the ferroelectric and piezoelectric properties. Pure CBNL and CBNL:xMn ceramics have maintained their pseudo-tetragonal phase boundary even after the insertion of Mn ions. The addition of MnO2 in CBNL has improved the multifunctional properties of material at x = 0.20. CBNL:0.20Mn has shown the relative density of 98%, saturated polarisation (PS ) of ~ 13.5 µC/cm2, high piezoelectric coefficient (d33 ) of ~ 25 pC/N, and high impedance of ~ 8.9 × 108 Ω at room temperature, which are the much improved values as compared to pure CBN or CBNL ceramics. The dielectric constant (ɛr ) dependence on temperature is presenting the sharp peak of CBNL:0.20Mn ceramic at Curie temperature (TC ) ~ 918°C confirming the strong ferroelectric nature of the ceramic. Importantly, poled CBNL:0.20Mn ceramic has shown the thermally stable depoling performance, which remains 92% (23 pC/N) of its initial room temperature value even after annealing the sample at 800°C. Results indicate the clear significance that the introduction of multivalence Mn ions in the pseudo-tetragonal existent region of CBNL has improved the multifunctional properties of the material, making it a strong candidate to be utilised in actuators and high-temperature piezoelectric devices.

ELEMENTS OF TECHNOLOGY FOR THE SURFACE GIPSUM COMPOSITE AND ITS PROPERTIES, AS A FACING MATERIAL

The paper considers the issues of obtaining a composite material based on gypsum, fly ash and sulfur with improved performance. Regularities of impregnation of a gypsum sol matrix with a sulfur melt are established, taking into account the capillary-porous structure of the gypsum sol stone and the physical and technical properties of sulfur. The conducted studies make it possible to determine the sulfur mass transfer coefficient ams and the maximum sulfur-containing Us in impregnated products, depending on the initial values of the sulfur melt temperature, water-solid ratio and fly ash content. This allows to determine quickly and effectively the duration of impregnation to a given sulfur content for a specific composition and size of gypsum products. Technological factors influencing the hardening coefficient, water resistance and chemical resistance of gypsum ash products impregnated in sulfur melt have been studied. An analysis of the results shows that the strength of samples impregnated with sulfur increases while the degree of filling of the pore space with it is increasing. So, with increase in the relative sulfur content (v = Us / Usmax) from 0.30 to 0.90, the compressive strength increases from 10.1 to 42 MPa. It has been established that water resistance of the impregnated samples significantly depends on the degree of impregnation and the amount of fly ash. The experiments carried out give reason to believe that the material based on gypsum, ash and sulfur refers to waterproof materials, since the softening coefficient is higher than 0.7. It has been established that gypsum and gypsum samples impregnated with sulfur melt have a chemical resistance coefficient of at least 0.7, which allows them to be classified as chemically resistant. The resulting sulfur-gypsum composite is distinguished by high strength, water and corrosion resistance to aggressive environments of livestock complexes, food and chemical industries, where it should be used in the form of special facing products.

Flame 3D temperature field reconstruction based on Damped LSQR-LMBC

Light field camera can solve the problems of complex optical path and difficult synchronous trigger of radiation temperature measurement multi camera system, which has some unique advantages in three-dimensional temperature reconstruction of radiation imaging. The LSQR is a classical algorithm for solving the least square problem based on large sparse matrix. When the algorithm is used to reconstruct three-dimensional temperature field, it depends on the initial value of temperature, and the reconstruction accuracy is not ideal when the signal-to-noise ratio is low. In this paper, a damped LSQR-LMBC reconstruction algorithm is proposed. By adding a damped regularization term into the LSQR method, the anti noise performance of flame three-dimensional temperature field reconstruction is improved. By combining the LMBC algorithm, the absorption coefficient and three-dimensional temperature field are solved at the same time. In the numerical simulation part, with the gradual reduction of signal-to-noise ratio, the reconstruction effect of Damped LSQR turns more stable than LSQR. When the signal-to-noise ratio reaches 13.86 dB, the reconstruction accuracy is improved by about 30%. The average reconstruction error of damped LSQR-LMBC is 6.63%. The three-dimensional temperature field distribution of butane flame is consistent with the characteristic of radiation flame combustion. Compared with the temperature measurement data of thermocouple, the relative error is about 6.8%.

Finite Element Analysis of The Thermal Behaviour of Different Types of Connecting Rod for Various Materials

Thermal analysis of different types of the connecting rods are under stead state condition using finite element method. The energy equation and heat transfer equation in the solids are completely addressed and solved using the Newton-Raphson technique and finite element method. SOLID WORKS is used for modelling different types of connecting rods and ANSYS© software is used to perform this numerical investigation. Three different materials like structural steel, aluminium alloy and titanium are selected as the material of connecting rod to do the comparative studies. In a steady thermal analysis, properties like temperature distribution, total heat flux and directional heat flux are calculated. The knowledge of the above properties is required to identify the viscosity of oil used for lubrication and also temperature distribution is helpful to find the thermal deformation in the connecting rod. Temperature and convection co-efficient are the boundary conditions. 22°C is the initial temperature value and the value of convection co-efficient is 350W/m2°C. As a result of thermal analysis, titanium alloy is the best material among the three materials as it with stand higher temperatures, high lifecycle and high performance.

Analysis on the Morphology and Quality Characteristics of Different Varieties of Lotus Root Starch and Whole Powder

The present work reports the differences in the between particle morphology, gelatinization properties, thermal properties and texture propertiesmorphology and quality characteristics of starch particles and whole powders obtained from six different varieties of lotus root. The results showed that the surface of lotus root starch particles was smooth without cracks, but with depressions. Most of the particles were short rod-shaped, but some were elliptical; the whole lotus root powder had rough surface and irregular shape. There was no significant difference between lotus root starch and whole flour in the brightness, but the transparency of starch wassignificantly higher than that of whole flour. The initial gelatinization temperature and enthalpy change value of lotus root starch were higher than that of whole lotus root starch. The gelatinization temperature of starch particlesobtained from 'Hangzhouhuanghetou' was 63.9 ℃, the highest gelatinization temperature among testing samples. The gelatinization temperature of 'Elian No. 6'whole powder was 55.0 ℃, the lowest gelatinization temperature among testing samples.Lotus root starch had better expansion properties and thermal paste stability, and lotus root whole powder hadbetter cold paste stability. The chewiness and ductility of lotus root starch were generally lower than that of whole lotus root powder, butthe elasticity and hardness were similar. Among samples, the chewiness and ductility of starch and whole lotus root starch obtained from 'Elian No. 1' were higher than other varieties.

К вопросу об определении барометрической высоты механическим альтиметром и системой воздушных сигналов

Reliable information on the altitude and speed parameters of the aircraft (AC) is required for safety and increasing the efficiency of flight missions. In this regard, the task of studying the features and improving the characteristics of existing meters for these parameters is quite urgent. Purpose of the study. The features of determining the barometric altitude of an aircraft by a mechanical indicator and an air signal system (SHS) are considered. Materials and methods. The essence of the baro¬metric method for measuring the altitude of the aircraft is analyzed, it is found that to build a clear theory of the method, it is necessary to know the dependence of the temperature of the atmosphere on the altitude. Moreover, it is known that this temperature usually decreases with increasing altitude. However, the rate of decrease unpredictably changes both at different times of the year and day, and at different points and at different heights. Moreover, in some cases, in a certain range of heights, the temperature may not decrease, but, on the contrary, increase. In this regard, there is some problem with the formalization of this dependence. When constructing a theory of the method for mechanical pointers, one proceeds in such a way that the dependence for the International Stan¬dard Atmosphere (ISA) is used, in which temperature and pressure are uniquely related. When developing algorithmic support for SHS, it is considered that the temperature decreases with height as well as in a standard atmosphere, but its actual value at the level of the reference plane can be anything that is not at all related to pressure and altitude in ISA. For this purpose, a temperature control unit is provided in the SHS at the level of the height reference plane. Results. A formula has been obtained that makes it possible to determine the difference between the readings of a mechanical altimeter and SHS. It was found that this difference is a function of pressure and temperature at the level of the plane of the altitude reference plane, as well as the actual pressure at the flight altitude. Numerical studies have been carried out to assess the discrepancy between the readings. It has been established that the relative difference in readings can reach the order of magnitude under ope¬rating conditions, and it practically does not depend on the aircraft altitude and is, in essence, a constant for the indicated initial values of pressure and temperature (at the level of the plane of the altitude reference). Conclusion. The developed algorithms can be used to improve the algorithmic support of the SHS.

Mechanical behaviors of tunnel lining in uneven temperature field of high geothermal surrounding rock

Because of large temperature difference between inside and outside of tunnel lining in high ground temperature environment, thermal stress is easy to occur in the structure, which affects the stability of tunnel lining. In this paper, a three-dimensional thermo-mechanical coupled numerical model of rock stratum-tunnel is established based on a tunnel project with high geo-temperature, and the stress of tunnel lining under high geo-temperature environment is calculated and analyzed, the influence of temperature distribution on lining stress is analyzed. The results show that the principal stress and surrounding rock pressure increase with the increase of temperature at the initial stage of lining. When the temperature field is not uniform, the stress concentration is easier at the corner of the initial support of the high temperature side. When the temperature difference between the left and right sides of the lining is constant, the surrounding rock pressure ratio between the high temperature side and the low temperature side is basically the same. However, the pressure difference of surrounding rock increases with the increase of the initial temperature value. Therefore, the unfavorable temperature field distribution of surrounding rock should be carefully handled in tunnel design and construction. The research results of this paper will provide some reference value for the design and construction of similar tunnel with temperature and heat damage in highland.

Simulation of nanofluid-cooled lithium-ion battery during charging: A battery connected to a solar cell

In this study, a lithium-ion battery hybrid cooling system is designed to cool the battery using nanofluid and extended surfaces (microchannels). The battery connected to a solar system is evaluated during charging mode. Initially, according to topology optimization based on the maximum heat transfer and minimum pressure drop, the model with maximum efficiency is proposed. A non-Newtonian hybrid nanofluid containing carbon nanotubes flows inside it. Numerical simulations are performed for this system. The Galerkin finite element algorithm is used to perform the calculations and the simulated results are performed to analyze the flow behavior and heat transfer of non-Newtonian nanofluid around the battery. The results demonstrate that the use of the A-3 model at the Reynolds number of 100 creates the lowest maximum temperature in the battery cell, which is 0.4 °C lower than that in the classic model. Also, at a Reynolds number of 1000, model A-2 has the lowest maximum temperature among different models, which is 0.11 °C lower than the classic model. The use of hybrid nanoparticles in all models reduces initial temperature value and enhances the amount of pressure drop at all Reynolds numbers. Among these, the classic model has the maximum and the A-4 model has the minimum pressure drop among different models at different Reynolds numbers, especially Re = 1000. Finally, it is revealed that adding carbon nanotubes to the base fluid and using the nanofluids in microchannels to cool the battery improves battery performance and enhances battery efficiency.

Thermal conditions of Adsorptive heat storage device operating in open-mode for heating inflowing air

Thermal conditions of adsorptive heat storage device operating in open-mode were considered when discharged. The main operating parameters affecting the final temperature of airflow which supplied to ventilated premises are determined on the example of heat storage device based on composite ‘silica gel – sodium sulphate’. The main factors which determine a final airflow temperature are confirmed to be initial values of temperature, absolute humidity and speed of airflow which fanned to the adsorbent layer. Algorithm of calculating the operational parameters of adsorptive heat storage device has been further developed. Proposed algorithm involves calculation of diffusion coefficient, mass transfer coefficient, final absolute humidity of airflow, volume of air which passed through adsorbent layer, adsorption, specific adsorption heat and final airflow temperature, then useful heat, heat inputs for operating heat storage device and its efficiency factor are estimated. The adequacy of the proposed algorithm has been confirmed according with experimental data for operating of open mode adsorptive heat storage device. Curves final temperature of inflowing air vs. time of discharge of heat storage device are stated to depend on characteristics of airflow which fanned to the adsorbent layer such as temperature, speed and initial absolute humidity. When these parameters increased, time to achieve plateau, i.e. maximal values of final inflowing air temperature decrease. The dependence of initial values of temperature, absolute humidity, speed of humid airflow and final airflow temperature is shown. Maximal temperatures of at most 65 – 80 ºC are stated at the initial temperatures and absolute humidity of initial airflow within the ranges of 20 – 30 ºC and 0.03 – 0.04 kg/m3, respectively. The results of the present study can be used for the development of energy-efficient systems and devices for air-conditioning in habitual inner space and warehouses.

A transient heat conduction phenomenon to distinguish the hydrodynamic and (quasi) ballistic phonon transport

Previous studies have predicted the failure of Fourier’s law of thermal conduction due to the existence of wave like propagation of heat with finite propagation speed. This non-Fourier thermal transport phenomenon can appear in both the hydrodynamic and (quasi) ballistic regimes. Hence, it is not easy to clearly distinguish these two non-Fourier regimes only by this phenomenon. In this work, the transient heat propagation in homogeneous thermal system is studied based on the phonon Boltzmann transport equation (BTE) under the Callaway model. Given a quasi-one or quasi-two (three) dimensional simulation with homogeneous environment temperature, at initial moment, a heat source is added suddenly at the center with high temperature, then the heat propagates from the center to the outer. Numerical results show that in quasi-two (three) dimensional simulations, the transient temperature will be lower than the lowest value of initial temperature in the hydrodynamic regime within a certain range of time and space. This phenomenon appears only when the normal scattering dominates heat conduction. Besides, it disappears in quasi-one dimensional simulations. Similar phenomenon is also observed in thermal systems with time varying heat source. This transient heat propagation phenomenon of hydrodynamic phonon transport distinguishes it well from (quasi) ballistic phonon transport.

Upcycling Postconsumer High-Density Polyethylene (PC-HDPE): Thermal Stability and Kinetics Study of the Filaments Extruded from PC-HDPE

Thermal stability and kinetics of thermolysis of postconsumer milk containers made of high-density polyethylene (PC-HDPE) and filament rods extruded from them (HDPE-F) were examined by thermogravimetric analysis (TGA) with six linear temperature programs under a stream of nitrogen. The total weightloss of each sample took place in a one-step decomposition to volatiles at the heating rates, β = 1, 10, 25, 50, 70, and 100 Kmin-1. The values of initial decomposition temperature, the temperature at the maximum thermal degradation rate, and the maximum rate of decomposition were increased by increasing the heating rate as was the expectation. The isoconversional method was used to evaluate the fundamental kinetic parameters, the activation energy barrier (Ea ), the Arrhenius pre-exponential factor (A), and the mechanism of the reaction, f(α). The values of Ea were independent of the model and heating rate, as was expected. However, the values of A depended on the model and the extent of reaction (α). The values of the Ea of PC-HDPE initiated at 171 kJ/mol at α = 0.05 and it increased to 207 kJ/mole at α = 0.95. The values of Ea of the HDPE-F rod were relatively constant for all α values, being 227 ± 3 kJ/mol. It was justified by the absence of easily volatilized substances in the HDPE-F. Knowledge of the thermal stability and decomposition kinetics of the starting materials (PC-HDPE) and the product (HDPE-F) is important in the context of thermochemical conversion processes aimed at the use of PC-HDPE as raw materials for recycling, upcycling, and down-cycling for objects used under room conditions.

Modelling of runaway electron dynamics during argon-induced disruptions in ASDEX Upgrade and JET

Disruptions in tokamak plasmas may lead to the generation of runaway electrons that have the potential to damage plasma-facing components. Improved understanding of the runaway generation process requires interpretative modelling of experiments. In this work we simulate eight discharges in the ASDEX Upgrade and JET tokamaks, where argon gas was injected to trigger the disruption. We use a fluid modelling framework with the capability to model the generation of runaway electrons through the hot-tail, Dreicer and avalanche mechanisms, as well as runaway electron losses. Using experimentally based initial values of plasma current and electron temperature and density, we can reproduce the plasma current evolution using realistic assumptions about temperature evolution and assimilation of the injected argon in the plasma. The assumptions and results are similar for the modelled discharges in ASDEX Upgrade and JET. For the modelled discharges in ASDEX Upgrade, where the initial temperature was comparatively high, we had to assume that a large fraction of the hot-tail runaway electrons were lost in order to reproduce the measured current evolution.

Comparative study on high temperature thermal stability of quaternary nitrate-nitrite mixed salt and Solar salt

Molten salts are applied in solar thermal power plant as heat transfer and heat storage medium. In this work, the thermal stability of quaternary nitrate-nitrite (QNN) mixed salt and Solar salt are studied under three constant temperature conditions (500 °C, 565 °C, 600 °C) for 1008h. The results show that the mass ratio of N O 2 − 1 / N O 3 − 1 plays an important role in the thermal physical properties of nitrite/nitrate molten salt. The mass ratio of N O 2 − 1 / N O 3 − 1 in Solar salt increases with the increasing of working temperature, which results in the decreasing of melting point and initial crystal temperature and the increasing of decomposition temperature. The average values of melting point and initial crystal temperature of QNN mixed salt are maximum 119 °C and 24 °C lower than that of Solar salt. Meanwhile, the maximum increase of average values of specific heat and thermal conductivity of QNN mixed salt are 14.26%, 8.18% compared with its base salt, respectively. When the working temperature is higher than decomposition temperature, average values of specific heat and thermal conductivity of Solar salt decrease because of the acceleration of nitrite formation. The viscosity values of QNN mixed salt and Solar salt decrease with the increasing of temperature. Based on the comparative analysis, QNN mixed salt has good application value in practical engineering applications. • The long-time thermal stability of QNN mixed salt and Solar salt are studied. • Nitrite/nitrate ratio plays an vital role in molten salt thermal physical property. • The thermal physical performance of QNN mixed salt is better than Solar salt.

Development and validation of an asymptotic solution for a two-phase Stefan problem in a droplet subjected to convective boundary condition

Droplet solidification is governed by classical Stefan problems which have been commonly treated as a single-phase problem by the majority of the studies in the literature. This approach, however, is unable to capture the initial temperature and the start of freezing time correctly. The treatment of two-phase Stefan problem in spherical coordinates is limited. No known exact solution exists, albeit numerical solutions and asymptotics have proven to be useful. We present a singular perturbation solution in the limit of low Stefan number and arbitrary Biot number for the two-phase Stefan problem in a finite spherical domain. An asymptotic solution is developed for a droplet at a non-freezing initial temperature subjected to a convective boundary condition at the surface. The solution is developed for both long-time and short-time scales. The results from asymptotic expansion method are validated with the experimental results in the literature and are further verified by a numerical model of a freezing droplet using enthalpy–porosity method. The sensitivity of the asymptotic solution to the droplet initial temperature, Biot number, and Stefan number has also been studied. The results indicate that the solution from perturbation series and enthalpy–porosity method agrees to within 1%–10% for temperature profile and overall freezing times over a wide range of practical values for initial temperature, Stefan and Biot numbers for the application of spray freezing. Our perturbation series solution is also able to capture the effect of initial temperature on the overall freezing time of the droplet.

Simultaneous NOx and SO2 removal during wet flue gas desulfurization, using copper smelter slag slurry combined with yellow phorphorus

AbstractThe study of copper slag has attracted the attention of scholars from both China and around the world. But few have paid attention to its applications in the simultaneous removal of SO2 and NOx in wet flue gas desulfurization (WFGD), becasue WFGD technique is inappropriate for directly treating NOx owing to the low solubility of NO. This work aims to improve NOx removal efficiency in WFGD technology using copper slag slurry associated with the oxidation of NOx by yellow phosphorus. Different operating conditions, including dispersion of P4, solid‐liquid ratio, initial pH value of copper slag slurry, reaction temperature, oxygen content, and gas flow rate, were compared regarding the efficiency of SO2 and NOx simultaneous removal. The characterizations were carried out on the liquid and solid part of fresh and spent copper slag slurry after filtration. The results indicated that a great amount of metals ions, such as Fe3+ and Zn2+, were leached by reacting with produced acids (H2SO4, HNO3, and H3PO4), which had a liquid‐phase catalytic oxidation on SIV species (SO32−/HSO3−), leading to promotion in absorption for SO2. The copper slag played a significant role in dispersing the yellow phosphorus and promoting ozone generation, thus improving NOx removal efficiency. The reaction pathway can be divided into three parts: (a) ozone generation induced by yellow phosphorus, (b) the oxidation of NO by O3 and then dissolution in aqueous solution, and (c) the dissolution of SO2 and the liquid‐phase oxidation for SO2 through metal ions produced by the reaction between acid and copper slag.

Peculiarity of long-term climate dynamics and its impact on the distribution and fishing of herring fish species in the Baltic Sea

The features of the interannual dynamics of the surface water temperature in the Central part of the Baltic Sea and in the Gulf of Finland over the past 70 years were analyzed. The total effect of the linear trend and the long-period component on the dispersion of the initial water temperature values in the Central part of the Baltic Sea was 48.4 %, and in the Gulf of Finland was 67.0 %. These two components in 1949–2018 determined the duration of two climatic phases: moderate (1949–1987) with a heat content close to normal and warm (1988–2018). The average rate of temperature increase in the last 31-year period (1988–2018) in the Central part of the Baltic Sea was 0.42 °C per 10 years, while in the Gulf of Finland it was 1.5 times higher. The beginning of the modern period of warming of water masses coincided with the weakening of the meridional type of atmospheric circulation in the North Atlantic and the strengthening of air transport from its water area in the Eastern direction. The increase of water temperature may be one of the reasons for the redistribution of commercial concentrations of herring and sprat in the Baltic Sea, thereby the change in their annual catch in certain ICES sub-divisions of the Central part of the Baltic Sea and the Gulf of Finland was observed.