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To effectively develop the rare earth elements resources from the geothermal waters, it is essential to understand the volumetric properties of the aqueous solution system to establish the relative thermodynamic model. In this study, densities of YCl3 (aq) at the molalities of 0.08837–1.60639 mol·kg−1 from 283.15 K to 363.15 K at 5 K intervals and ambient pressure were measured experimentally by an Anton Paar digital vibrating-tube densimeter. Based on experimental data, the volumetric properties including apparent molar volume (Vϕ) and the coefficient of thermal expansion of the solution (α) of the binary systems (YCl3 + H2O) were derived. The 3D diagram (mi, T, Vϕ) of apparent molar volumes against temperature and molality was plotted. On the basis of the Pitzer ion-interaction model of electrolyte, the Pitzer single-salt parameters ( β MX 0 v , β MX 1 v , and C MX v ) for YCl3 and temperature-dependence equation F(i, p, T) = a1 + a2ln(T/298.15) + a3(T-298.15) + a4/(620-T) + a5(T-227) as well as their coefficients ai (i = 1–5) in the binary system were obtained for the first time. The values of Pitzer single-salt parameters of YCl3 agree well with the calculated values corresponding to the temperature-dependence equations, indicating that single-salt parameters and temperature-dependent formula obtained in this work are reliable.

In the emerging edge computing scenarios, FPGAs have been widely adopted to accelerate CNN-based image processing applications, such as image classification, object detection, and image segmentation, etc. A standard image processing pipeline first decodes the collected compressed images from IoTs to RGB data, then feeds them into CNN engines to compute the results. Previous works mainly focus on optimizing the CNN inference parts. However, we notice that on the popular ZYNQ FPGA platforms, image decoding can also become the bottleneck due to the poor performance of embedded ARM CPUs. Even with a hardware accelerator, the decoding operations still incur considerable latency. Moreover, conventional RGB-based CNNs have too few input channels at the first layer, which can hardly utilize the high parallelism of CNN engines and greatly slows down the network inference. To overcome these problems, in this paper, we propose FD-CNN, a novel CNN accelerator leveraging the partial decoding technique to accelerate CNNs directly in the frequency domain. Specifically, we omit the most time-consuming IDCT (Inverse Discrete Cosine Transform) operations of image decoding and directly feed the DCT coefficients (i.e., the frequency data) into CNNs. By this means, the image decoder can be greatly simplified. Moreover, compared to the RGB data, frequency data has a narrower input resolution but has 64 × more channels. Such an input shape is more hardware-friendly than RGB data and can substantially reduce the CNN inference time. We then systematically discuss the algorithm, architecture, and command set design of FD-CNN. To deal with the irregularity of different CNN applications, we propose an image decoding aware design-space exploration (DSE) workflow to optimize the pipeline. We further propose an early-stopping strategy to tackle the time-consuming progressive JPEG decoding. Comprehensive experiments demonstrate that FD-CNN achieves on-average 3.24 ×, 4.29 × throughput improvement, 2.55 ×, 2.54 × energy reduction and 2.38 ×, 2.58 × lower latency on ZC-706 and ZCU-102 platforms respectively, compared to the baseline image processing pipelines.

In this paper, the solubilities and the densities of the ternary system (CsNO3 + NH4NO3 + H2O) at 298.15 and 348.15 K and 101.325 kPa were measured using the isothermal dissolution equilibrium method, and the phase diagrams and density versus composition diagrams at these two temperatures were established on the basis of experimental data for the first time. In the ternary system at both temperatures, there are all one invariant point, two solubility isotherm curves, and two crystallization zones corresponding to cesium nitrate (CsNO3) and ammonium nitrate (NH4NO3). The phase diagram at two temperatures belongs to the simple-type of salt–water system, neither double salt nor solid solution were formed. With increasing of the concentration of ammonium nitrate in solution at the two temperatures, the density of the solution is increased gradually, firstly to reach the maximum value at the invariant point, and then decreased gradually. Moreover, on the basis of empirical equations of density of the electrolytes, the calculated values of densities at the two temperatures agree well with the experimental data.

In this paper, in order to understand the thermodynamic properties of natural minerals of pinnoite (MgB2O4·3H2O, Pin) and inderite (Mg2B6O11·15H2O, Ind) deposited in salt lakes, heat capacities of two minerals were measured using a precision calorimeter at temperatures from 306.15 to 355.15 K after the high purity was synthesized. It was found that there are no phase transitions and thermal anomalies for the two minerals, and the molar heat capacities against temperature for Pin and Ind were fitted as Cp,m,pin = −2029.47058 + 16.94666T − 0.04396T2 + 3.89409×10−5T3 and Cp,m,Ind = −30814.43795 + 282.68108T − 0.85605T2 + 8.70708×10−4T 3, respectively. On the basis of molar heat capacities (Cp,m) of Pin and Ind, the thermodynamic functions of entropy, enthalpy, and Gibbs free energy at the temperature of 1 K interval for the two minerals were obtained for the first time.

This paper reports the molar heat capacities of β-CsB5O8·4H2O, which were measured by an accurate adiabatic calorimeter from 298 to 373 K with a heating rate of 0.1 K/min under nitrogen atmosphere. Neither phase transition nor thermal anomalies were observed. The molar heat capacity against temperature was fitted to a polynomial equation of Cp,m (J·mol−1·K−1) = 618.07702 + 39.52669[T − (Tmax + Tmin)/2]/(Tmax − Tmin)/2] − 3.46888[(T − (Tmax + Tmin)/2)/(Tmax − Tmin)/2]2 + 7.9441[(T − (Tmax+ Tmin)/2)/(Tmax − Tmin)/2]3. The relevant thermodynamic functions of enthalpy (HT − H298.15), entropy (ST − S298.15), and Gibbs free energy (GT − G298.15) of cesium pentaborate tetrahydrate from 298 to 375 K of 5 K intervals are also obtained on the basis of relational expression equations between thermodynamic functions and the molar heat capacity.

Solid–liquid phase equilibria of the ternary systems (NaB5O8 + KB5O8 + H2O) and (LiB5O8 + KB5O8 + H2O) at T = 298.15 K and p = 101.325 kPa were investigated, using a combination of the methods of isothermal dissolution equilibrium and the wet-residue solid phase (Schreinemarker’s rule). From the experimental results, the phase diagrams and the diagrams of physicochemical properties versus composition were drawn for each system. The phase diagrams of the systems (NaB5O8 + KB5O8 + H2O) and (LiB5O8 + KB5O8 + H2O) at 298.15 K contain one invariant point, two univariant curves and two crystallization regions. The area of the crystallization region of KB5O8·4H2O is much larger than that of NaB5O8·5H2O in the former system and that of LiB5O8·5H2O in the later system. Owing to the different solubilities of the salts in the aqueous systems, the solubility of KB5O8 in the solution decreased obviously with increasing concentration of NaB5O8 or LiB5O8 in either ternary system, indicating that both NaB5O8 or LiB5O8 have a relatively strong effect on the solubility of KB5O8. It was found that both systems belong to the simple eutectic type, and neither double salts nor solid solutions were formed. The distribution behaviors of densities and refractive indices in the two ternary systems at 298.15 K are similar and change regularly with increasing KB5O8 concentration in each system. The density and refractive index calculated on the basis of empirical equations of salt–water electrolytes agree well with the experimental values.

Equilibria data and the physicochemical properties including density and refractive index for the ternary system (KCl + KBO2 + H2O) at 298.15 and 323.15 K were determined and proposed with the isothermal dissolution equilibrium and wet-reside solid phase (Schreinemarkers rule) methods. Also, the phase diagram and chart of physicochemical properties were constructed based on experimental data. For both temperatures, one invariant point, two univariant curves, two crystallization regions corresponding to KCl and KBO2·4/3H2O were found. Noticeably, with the rise of temperature, the solubilities of the single salts of KCl and KBO2·4/3H2O become large; meanwhile, the solubilities data at the invariant point also increase. What’s more, the physicochemical properties, including density and refractive index, change systematically in the wake of the concentration of potassium chloride, and due to the increase of solubilities along with the augment of temperature, the density and refractive index at 323.15 K have been increased compared at 298.15 K. The calculated values of the density and refractive index correlated using the empirical equations were consistent with the experimental data and the parameters obtained in our work are authentic.

The salt-water interactions on single salt aqueous solutions of cesium sulfate and cesium chloride, as well as their mixing solutions, have been investigated by a combination of density measurements by an Anton Paar Digital vibrating-tube densimeter and the correction of the Pitzer model of electrolyte. The volumetric properties including apparent molar volume (Vϕ) and the coefficient of thermal expansion of the solution (α) of the binary systems (CsCl + H2O), (Cs2SO4 + H2O) and the ternary system (CsCl + Cs2SO4 + H2O) from 283.15 to 363.15 K at 5 K intervals and atmospheric pressure were derived. Variation trends of these volumetric properties against temperature and molality were revealed minutely. The Pitzer single salt parameters ( β MX 0 v , β MX 1 v and C MX v , MX = CsCl and Cs2SO4), mixing ion-interaction parameters ( θ Cl , S O 4 v and ψ Cs , Cl , S O 4 v ) as well as the correlation coefficient ai in the temperature-dependence equation (F(i, p, j) = a1 + a2ln(T/298.15) + a3(T-298.15) + a4/(620-T) + a5/(T-227)) have been obtained according to Pitzer ion-interaction model of electrolytes. These results are helpful to understanding the ion-interaction of aqueous solutions.

As a new-type of liquid mineral resource of cesium including salt lake brine, geothermal water, underground water and seawater, the recovery of cesium is of great significance for its importance strategic purpose in modern industry, and the parameterization of ion-interaction model is essential to understand the ion-interaction of cesium borate solutions. In this paper, the dilution enthalpies on Cs2B4O7 aqueous solutions from 0.03900 to 0.54815 mol·kg−1 and CsB5O8 aqueous solutions from 0.02072 to 0.09889 mol·kg−1 at 298.15 K and 1.325 kPa were determined by the high-precision adiabatic microcalorimeter BT2.15 (Setaram, France), and the dissolution enthalpies for Cs2B4O7·5H2O and CsB5O8·4H2O were measured by the multi-channel microcalorimeter TAM-IV (TA, America). On the basis of experimental dilution enthalpies, the apparent molar enthalpies of Cs2B4O7 and CsB5O8 aqueous solutions were derived, and the diagrams of apparent molar enthalpy against molalities of Cs2B4O7 and CsB5O8 in aqueous solutions were plotted. And then, according to the Pitzer ion-interaction model of apparent molar enthalpy of electrolyte, Pitzer single parameters i.e. FMX ( β MX 0 L , β MX 1 L , β MX 2 L and C MX L , M = Cs+, X = [B4O5(OH)4]2− or [B5O6(OH)4]−) were obtained for the first time. The calculated apparent molar enthalpies for Cs2B4O7 and CsB5O8 aqueous solutions agree well with the experiment values, indicating that the single salt parameters obtained for Cs2[B4O5(OH)4] and Cs[B5O6(OH)4] in this work are reliable.

The isopiestic equilibria for the systems {Li2B4O5(OH)4 + H2O}, {LiB5O6(OH)4 + H2O} and {Li2B4O5(OH)4 + LiB5O6(OH)4 + H2O} at 288.15 K and ambient pressure were measured by the isopiestic method using a modified gravimetric isopiestic apparatus. The water activities and osmotic coefficients were determined based on the sodium chloride standard reference solution. On the basis of Pitzer model, an extended Pitzer model was developed to describe the thermodynamic properties of the aqueous systems containing different forms of lithium borates, then the Pitzer single salt parameters β(0), β(1), β(2) and Cϕ for the binary systems {Li2B4O5(OH)4 + H2O} and {(LiB5O6(OH)4 + H2O} and mixing ion-interaction parameters θ B 4 O 5 OH 4 , B 5 O 6 OH 4 and ψ Li , B 4 O 5 OH 4 , B 5 O 6 OH 4 for the ternary system {Li2B4O5(OH)4 + LiB5O6(OH)4 + H2O} were fitted with the experimental osmotic coefficients using the Fortran 97 program. Meanwhile, the water activities were calculated by the Pitzer parameters, and the good agreement between the calculated water activities and experimental results of this ternary system indicated that the Pitzer parameters obtained in this work were reliable.

This paper reports the densities of CsB5O8 (aq) in the range of salt concentrations from 0.02526 to 0.08148 mol·kg−1, which were determined by an accurate Anton Paar Digital vibrating-tube densimeter at 5 K intervals from 283.15 to 363.15 K and 101 kPa. The apparent molar volume (Vϕ), the coefficient of thermal expansion (α), apparent molar expansibility of the solute (ϕE) were calculated and variations of these properties against temperature and concentration were revealed minutely. According to Pitzer ion-interaction apparent molar volume model of aqueous electrolyte system, the Pitzer single salt parameters i.e. FMX ( β M X 0 v , β M X 1 v and C M X v , M = Cs+, X = [B5O6(OH)4]-), the temperature-dependence equation [FMX (i, p, T) = a1 + a2ln(T/298.15) + a3(T-298.15) + a4/(620-T) + a5(T-227), i = β M X 0 v , β M X 1 v and C M X v ] as well as their coefficients ai (i = 1 to 5) in the binary system were obtained, which is not reported in the literature. The fitted results of single salt parameters β M X 0 v , β M X 1 v and C M X v were in good agreement with the experiment values, indicating that the single salt parameters and temperature relational coefficients for Cs[B5O6(OH)4] obtained in this work are reliable.

Densities for aqueous solutions of Cs2B4O7 at the molalities of (0.16635–0.69694) mol·kg−1 were measured with an Anton Paar Digital vibrating-tube densimeter at temperatures from 283.15 K to 363.15 K and 101 kPa. According to experimental data, apparent molar volume (Vϕ), partial molar volume ( V ¯ ϕ ), and the coefficient of thermal expansion (α) of the Cs2B4O7 aqueous solution were calculated, and their distributive behaviors against temperature and molality have been discussed in details. Considering the structure of Cs2B4O7 in aqueous solution system is in the form of Cs2[B4O5(OH)4], the Pitzer single-salt parameters ( β M , X 0 v , β M , X 1 v , β M , X 2 v and C M , X v ) for Cs2[B4O5(OH)4] as well as temperature-dependence correlations were obtained for the first time on the basis of Pitzer ion-interaction apparent molar volume model of electrolytes. The deviations between the Pitzer single-salt parameters of Cs2[B4O5(OH)4] fitted at each temperatures based on the experimental data and those of the calculated values corresponding to the temperature-dependence equations on Pitzer single-salt parameters are all within ±0.1, indicating that the single-salt parameters and their temperature-dependence equations obtained in this work are reliable.