Search

The electrified cleaning agent requires a moderate volatilization rate, low ozone-depleting substances value, non-flammable, non-explosive and other characteristics. This study performed a whole life cycle assessment on a hydrocarbon-based electrified cleaning agent. The life cycle model is cradle-to-grave, and the background data sets include power grid, transportation, high-density polyethylene, chemicals, etc. The analysis shows that the global warming potential (GWP) of the life cycle of 1 kg of electrified cleaning agent is 2.08 kg CO2 eq, acidification potential (AP) is 9.49E-03 kg SO2 eq, eutrophication potential (EP) is 1.18E-03 kg PO43-eq, respirable inorganic matter (RI) is 2.13E- 03 kg PM2.5 eq, ozone depletion potential (ODP) is 4.91E-05 kg CFC-11 eq, photochemical ozone formation potential (POFP) is 2.89E-02 kg NMVOC eq, ionizing radiation-human health potential (IRP) is 3.16E-02 kg U235 eq, ecotoxicity (ET) is 2.69E-01 CTUe, human toxicity-carcinogenic (HT-cancer) is 4.32E-08 CTUh, and human toxicity-non-carcinogenic (HT-non cancer) is 2.31E-07 CTUh. The uncertainty of the results is between 3.46-9.95%. The four processes of tetrachloroethylene production, D40 solvent oil production, tetrachloroethylene environmental discharge during product use, and electricity usage during product disposal have substantial effects on each LCA indicator, so they are the focus of process improvement. Changes in power consumption during production and transportation distance of raw materials have little effect on total carbon emissions. Compared with the production process of single-solvent electrified cleaning agent tetrachloroethylene and n-bromopropane, the production of the electrified cleaning agent developed in this study has its own advantages in terms of carbon footprint and other environmental impact indicators. Carbon emissions mainly come from the power consumption of each process, natural gas production and combustion, and other energy materials for heating. It is recommended to use renewable raw materials instead of crude oil to obtain carbon credits based on geographical advantages, and try to use production processes with lower carbon emissions, while the exhaust gas from the traditional production process is strictly absorbed and purified before being discharged.

Microalgae are a renewable source of dietary supplements, bioactive compounds, and potential energy. Once harvested, the microalgal medium is dewatered to form a slurry for downstream processing. This article outlines a process design for pumping the microalgae slurry. The pump requirements for delivering the Chlorella slurry with 5, 10 or 20 wt% solids at one tonne per hour (1,000 kg/h) and 10 bar were calculated. The 5 wt% microalgae slurry is a Newtonian fluid with a viscosity of 1.95 mPaA—s. The 10 wt% and 20 wt% microalgae slurries are non-Newtonian fluids, whose viscosity depends on the shear rate (g). The viscosity of 10 wt% and 20 wt% microalgae slurries is 1.504 (g = 50 s -1 )/1.155 (g = 100 s -1 ) and 1.844 (g = 50 s -1 )/1.219 (g = 100 s -1 ) mPaA—s, respectively. The pump power requirements are mainly governed by the delivery pressure. The effect of the pipe length and the number of elbows is negligible. The effective power of the pump is calculated as 0.267-0.275 kW. To fulfill this duty, a ZGB type single-stage single-suction centrifugal slurry pump can be selected, which would provide enough shear rate to reduce the viscosity of the microalgae slurry and give required shaft power. Citation: Li, J., Qu, Y., Gong, Y., Yang, C., Yang, B., Liu, P., Zhang, B., and Ding, Y. (2020). Process Design of Microalgae Slurry Pump. Trends in Renewable Energy, 6(3), 234-244. DOI: 10.17737/tre.2020.6.3.00120

Advanced space materials are important to support the development of space technology. Their performance restricts the development of spacecraft to a great extent. However, the space environments encountered by spacecraft in orbit will lead to the degradation of material properties. The stability of the material in the space environment directly affects the performance level and service life of spacecraft. For the space radiation effects on space materials, a method to determine ground test parameters using depth-dose profile simulation is presented. By using this method, a ground test of the effects of space radiation environment in medium earth orbit for 8 years on carburized films was performed. The solar absorptance, infrared emittance, and surface resistivity of the test samples were measured. The results showed that the solar absorptance of the material changed significantly after irradiation, decreased by 10.3%, the infrared emittance decreased by 0.033, and the surface resistivity decreased slightly. The SEM photos indicated that the surface of the sample became rougher and there were more small holes. The XPS results indicated that the chemical bonds in the surface of samples changed under combined irradiation, and the C==O bond changed to C—O bond.

Presently, many regeneration processes of waste lubricating oil, such as catalytic hydrogenation, are available. However, some of these processes are highly costly and not suitable for Chinese economic conditions, and some may produce contaminated impurities such as acid slag, which cannot meet environmental protection requirements. This study aims to develop a green process for the regeneration of waste lubricating oil into a base oil, which should meet the requirements of green chemistry, have the characteristics of simple operation, low cost, less pollution and high recovery rate, and turn wastes into renewable resources. The new process developed via this research has three stages. First, mechanical and large particle impurities in the waste lubricating oil were removed by pretreatment. Second, most of the colloid and asphaltene were removed by thermal extraction and sedimentation. Finally, the activated bleaching earth was used to further purify the waste lubricating oil. The performance evaluation of the finally obtained lubricating base oil conformed to the standard of the HVI-100 lubricating oil. The total recovery rate of the process was about 63.5%. Citation: Wu, J., Li, B., Wang, W., Yang, S., Liu, P., Yang, C., and Ding, Y. (2019). Green Refining of Waste Lubricating Oil: A China Perspective. Trends in Renewable Energy, 5, 165-180. DOI: 10.17737/tre.2019.5.2.0084

Short Retraction Notice This article has been retracted to straighten the academic record. In making this decision the Editorial Board follows COPE's Retraction Guidelines. The aim is to promote the circulation of scientific research by offering an ideal research publication platform with due consideration of internationally accepted standards on publication ethics. The Editorial Board would like to extend its sincere apologies for any inconvenience this retraction may have caused. Please see the article page for more details. The full retraction notice in PDF is preceding the original paper which is marked "RETRACTED".

The solubility of a solid in a given solvent is decided jointly by its thermodynamic stability and the solute-solvent intermolecular forces. The melting point and enthalpy of melting of 1,9‑Nonanedioic acid as well as its heat capacities at solid and melt state were determined by DSC. The solubilities of 1,9‑Nonanedioic acid in ethanol, acetone, acetic acid and ethylene glycol were measured at temperatures from 276 to 337 K. The solubilities in the four solvents at constant temperature are in the order of ethanol > acetic acid > acetone > ethylene glycol while the temperature dependence is in the opposite order. The experimental solubility data were correlated with the van't Hoff, Wilson and the λh equations with the measured melting properties. The three models with optimized parameters are all able to reproduce the experimental data well, among which the λh equations has lowest average standard deviation and seems to be more consistent with the experimental data. Thermodynamic analysis of the obtained model parameters shows that the dissolution of 1,9‑Nonanedioic acid in the four solvents are all endothermic and mainly driven by the enthalpy change of the solution. The positive excess enthalpy of mixing the 1,9‑Nonanedioic acid melt and the solvent indicates the solute-solvent intermolecular interactions are dominated by repulsive forces.

With the development of the digital age, “digital learning and innovation” is becoming more and more important in the core literacy of information technology discipline. Through the elaboration of relevant concepts, this paper explores the connotation and concrete performance of “digital learning and innovation” literacy of senior high school students, and then obtains its three manifestations: the collection and management of digital learning resources, the adaptation of digital environment, the application and innovation of digital learning resources. On this basis, a questionnaire survey was designed to understand the status of “digital learning and innovation” literacy of high school students in S Middle School of Anhui Province, and the data results were analysed. It was found that senior high school students generally have this literacy, but some students still have some problems and need teachers’ timely guidance. Therefore, this study further proposes strategies for achieving high school students’ “digital learning and innovation” literacy to assist teachers in reminding students of “digital learning and innovation literacy” in teaching.

The single-event kinetic modeling approach is extended to the ethene oligomerization process with products including paraffins and olefins, cyclic molecules and aromatics. The reaction network of olefin oligomerization on ZSM-5 with elementary steps of de/protonation, isomerization, alkylation, β-scission, cyclization and hydride transfer is computer-generated and consists of 10,456 elementary steps involving 2567 species within the up to C8 range. The fast elementary steps: de/protonation and isomerization are considered to reach quasi-equilibrium. The single-event kinetics approach allows the reduction of the number of independent kinetic parameters to 30. The kinetics of the model was then applied to 13 groups of isomers continuity equation with the kinetic data obtained from experimentation in a fixed bed isothermal reactor. Five space times and three temperatures were investigated. The model parameters were obtained using a combination of the genetic algorithm and the Levenberg-Marquardt approach. The single-events model is capable of correctly simulating the experimental data.

Increasing demand for high-quality transportation fuels and stringent environmental standards have resulted in the significantly increased quantity of spent hydroprocessing catalysts, which require the sustainable management. To minimize the generation of hazardous wastes, the spent hydroprocessing catalysts can be regenerated via oxidative regeneration or reactivated via the rejuvenation process. If the catalytic activity cannot be restored, it can be utilized as a source of other useful materials, and/or metals in the spent catalyst are recovered. Finally, the stabilized residues shall be disposed by using an environmentally sound method. Citation:  Yang, C., Wu, J., Wang, W., Li, B., Zhang, B., and Ding, Y. (2018). Sustainable Management of Spent Hydroprocessing Catalyst. Trends in Renewable Energy, 4(1), 90-95. DOI:10.17737/tre.2018.4.1.0061

Densities and surface tensions of binary mixture of 1,2-diethoxyethane(DEE) and toluene have been measured over the entire composition at four temperatures of 293.15, 303.15, 313.15 and 323.15 K and atmospheric pressure. The trends in measured densities and surface tensions with respect to composition and temperature are discussed in detail and provide complementary information to each other. Excess molar volumes VE and surface tension deviations Δσ of the mixtures are directly calculated from experimental results and well correlated using the Redlich–Kister polynomial equation, which provides a simple tool for interpolation of these properties with fairly high accuracy. Other thermodynamic properties of partial molar volumes, thermal expansion coefficients, surface entropy and enthalpy are also calculated. The sign and magnitude of these quantities are discussed in terms of the nature of intermolecular interactions present in binary mixtures. The negative excess volume properties suggest that the formation of hydrogen bonds between DEE and toluene molecules and the geometrical packing effect are most likely to give rise to the volume contraction during mixing. The surface tensions of the mixture at all temperatures exhibit negative aneotropies and negative Δσ, which is considered as the outcome of intermolecular interactions between DEE and toluene and the prevalent adsorption of toluene at surface, according to the molding results derived using the Extended Langmuir equation.

New density and vapor–liquid equilibrium data of PCl3-benzene binary system at atmospheric pressure (99.7–101.3 kPa) were carefully measured to provide crucial information for their industrial reaction and separation. The experimental mixture densities show excellent linear dependence on both solution composition and temperature and a generalized empirical correlation is proposed with an average relative deviation of 0.13%. The specific attractive P-π interaction between the phosphorus atom of PCl3 and the π cloud of benzene seems to be quite strong in solution, leading to large negative excess volumes. But the π-π antibonding effect from benzene dimers are predominant in PCl3 highly dilute solution, where positive excess volume and excess partial molar volumes of PCl3 were observed. Experimental bubble points of the binary mixture were corrected to those under 101.325 kPa. Two distinctive methods of coexistence equation and activity coefficient models of Wilson and NRTL equations were applied to model the VLE data, and they yielded very consistent results. Although no azeotrope were found, this mixture exhibited quite low relative volatility.

Accurate density data of binary mixture of diisopropyl ether (DIPE) with acetone are essential for the engineering design and operation of their separation. Densities of acetone + DIPE binary mixtures have been measured over the entire range of composition and at temperatures from (283.15 to 323.15) K under atmospheric pressure. The volume-translated Peng-Robinson equation of state has been applied to predict the densities of the liquid mixtures with an overall average relative deviation of only 0.095%, yielding a substantial improvement to the untranslated Peng-Robinson equation with an average relative deviation over fifty times lower. Excess volumetric properties of excess molar volumes and excess isobaric expansibility coefficients are derived from the experimental density data and well correlated by the Redlich-Kister type polynomial equation. The resultant positive excess volumetric properties confirm the existence of dispersive interactions and dipolar/orientational order change in the binary mixture during mixing.

Understanding solid dissolution in polar binary solvents showing maximum or minimum solubility phenomenon is essential for the design and operation of anti-solvent crystallization process. Solubilities of 1,3-benzenedicarboxylic acid in binary solvents of acetone with water are measured from 278.15 to 323.15 K using the static equilibrium method, covering the entire range of solvent composition. The solubility always increases with increasing temperature, while, at fixed temperature, a maximum solubility is observed in mixed solvents of certain composition. The experimental temperature-dependent solubility data of 1,3-benzenedicarboxylic acid in cosolvents of different compositions are correlated using the Apelblat model with an average relative deviation (ARD) of 0.18%. Calculations of the derived thermodynamic functions show that the dissolution of 1,3-benzenedicarboxylic acid in the solvent mixtures is endothermic and mainly driven by the enthalpy change. The Simplified Modified Wilson (SMW) model is adopted to reproduce the isothermal solubility data over the entire acetone composition with an overall ARD of 1.41%, with which the maximum mole fraction solubility and the corresponding solvent composition at different temperatures are determined, and are subsequently used to estimate the solubility parameter of 1,3-benzenedicarboxylic acid.

The energy requirements for converting one tonne (1,000 kg) of Chlorella slurry of 20 wt% solids via fast pyrolysis, microwave-assisted pyrolysis (MAP), and hydrothermal liquefaction (HTL) were compared. Drying microalgae prior to pyrolysis by using a spray drying process with a 50% energy efficiency required an energy input of 4,107 MJ, which is higher than the energy content (4,000 MJ) of raw microalgae. The energy inputs to conduct fast pyrolysis, MAP, and HTL reactions were 504 MJ (50% efficient), 1,057 MJ (~25% efficient), and 2,776 MJ (50% efficient), respectively. The overall energy requirement of fast pyrolysis is theoretically about 1.6 times more than that of HTL. The energy recovery ratios for fast pyrolysis, MAP, and HTL of microalgae were 78.7%, 57.2%, and 89.8%, respectively. From the energy balance point of view, hydrothermal liquefaction is superior, and it achieved a higher energy recovery with a less energy cost. To improve the pyrolysis process, developing drying devices powered by renewable energies, optimizing the pyrolysis process (specifically microwave-assisted), and improving the energy efficiency of equipment are options. Citation: Zhang, B., Wu, J., Deng, Z., Yang, C., Cui, C., and Ding, Y. (2017). A Comparison of Energy Consumption in Hydrothermal Liquefaction and Pyrolysis of Microalgae. Trends in Renewable Energy , 3(1), 76-85. DOI: 10.17737/tre.2017.3.1.0013

Two novel carboxylic acid based ionic liquids (ILs), benzyltributylammonium myristic acetate ([N444Bn][MA]) and benzyltributylammonium dodecanedioic acetate ([N444Bn]2[DDA]), have been rationally designed and successfully synthesized for the extraction of yttrium (denoted as Y(III)) from a chloride aqueous solution and for the separation of mixed rare earth elements (REEs). Comparison studies of the extraction performances of [N444Bn][MA] and [N444Bn]2[DDA] were carefully investigated under different conditions (e.g., equilibrium time, solution acidity, salting-out agent concentration, and REEs concentration). The results indicated that the extraction efficiency of Y(III) reached 87.18% after 2 min using [N444Bn]2[DDA], whereas it required 10 min to reach an extraction efficiency of 47.37% using [N444Bn][MA], mainly due to the larger electronegativity of the incorporated dicarboxylates in the anions of [N444Bn]2[DDA], which enhanced its coordination with Y(III) compared to [N444Bn][MA]. However, [N444Bn][MA] illustrated better selective separation behavior than [N444Bn]2[DDA] in mixed REEs solutions (including La, Nd, Eu, Ho, Yb and Y), and the selective factors of Yb and La were 16.21 and 3.30, respectively. Furthermore, the ion association mechanism, evolved from the slope analysis and FT-IR results, contributed to avoiding the saponification procedures and resultant saponification wastewater during the extraction process. In addition, the back-extraction experiments indicated that ~97% Y(III) can be stripped from [N444Bn]2[DDA] and [N444Bn][MA] using 1.0 M and 0.4 M HCl, respectively, demonstrating that these ILs can be further used in large-scale applications for the separation and recovery of REEs.

Three inexpensive N-heterocyclic hyper-cross-linked polymers (HCP-IN, HCP-BZD, and HCP-BTA) were successfully prepared by Friedel−Crafts reaction for the removal of organic pollutants from aqueous solution. Five organic pollutants, i.e., 1-naphthol (1-NO), 4-nitrophenol (4-NP), 4-chlorophenol (4-CP), 2,4-dimethylphenol (2,4-DMP), and phenol were selected. Because of high specific surface area (1023 m2/g), micropore specific surface area (622 m2/g), and good wetting ability, HCP-BTA showed ultra-fast adsorption. Its adsorption capacity can reach up to 490.9 mg/g for 1-NO, 363.2 mg/g for 4-NP, 345.8 mg/g for 4-CP, 310.4 mg/g for 2,4-DMP, and 18,130.9 mg/g for phenol, within 1 min. The process was exothermic, and ΔH had an order of 1-NO (−116.23 kJ/mol) > 2,4-DMP (−89.26 kJ/mol) > 4-NP (−59.74 kJ/mol) > 4-CP (−41.12 kJ/mol) > phenol (−18.61 kJ/mol). The adsorption mechanism was explored as well. Hydrogen bonding, π–π stacking, and hydrophobic interaction might be the significant interactions for the adsorption. Besides, HCP-BTA can be easily regenerated, and the capacity after five cycles still remained 90% of the first adsorption. Above all, the N-heterocyclic hyper-cross-linked polymers may be the promising candidate for the removal of organic pollutants from aqueous solution.

Diethylamine, ethyl acetate and triethylamine are usually applied to synthesize an important flame retardant of vinylphosphorus, which has high ability to retard flames, low toxic content, and good washing durability. The isobaric VLE data of (diethylamine + triethylamine, diethylamine + ethyl acetate) and (ethyl acetate + trimethylamine) system were determined at 101.3 kPa for industrial separation. A minimum azeotrope was discovered at x = 0.8217 in the (ethyl acetate + trimethylamine) system. Therefore, a series of experiments were designed to investigate the effect of diethylamine on the (ethyl acetate + trimethylamine) system and the results indicated that the azeotrope can be eliminated when the liquid mole fraction of diethylamine is greater than 0.4687. Furthermore, molecular dynamics analysis through GROMACS software and Multiwfn software was also used to study the interaction of these three materials in this work. The results show that the weak interaction force around ethyl acetate decreases after adding diethylamine, which means that the van der Waals effect and the electrostatic effect of ethyl acetate become smaller. This may be the main reason why the azeotropic point of the (ethyl acetate + trimethylamine) system disappears.

Recently, algae have been considered as the third-generation biofuel feedstock, which can be converted to the precursor chemicals of drop-in fuels via either the algal lipid upgrading (ALU) pathway or the hydrothermal liquefaction (HTL) pathway. These precursors could be further processed and upgraded to fuels. This article reviews the standards and protocols that are suitable for characterization of drop-in algal biofuels. Applicable ASTM standards and European standards (EN) were summarized. The protocols that have been used by researches and the National Institute of Standards and Technology were also introduced. Citation: Yang, C., Zhang, B., Cui, C., Wu, J., Ding, Y., and Wu, Y. (2016). Standards and Protocols for Characterization of Algae-Based Biofuels. Trends in Renewable Energy, 2(2), 56-60. DOI: 10.17737/tre.2016.2.2.0022

Suitable solvent and the related solution thermodynamics of fosfomycin phenylethylamine (FPEA) are essential for its purification by cooling crystallization. Two candidate solvents of ethanol and water are systematically investigated and compared, including the solubilities in them from 278.15 to 348.15 K with an interval of 5 K and the dissolution enthalpies at different concentrations at 303.15 K, which were measured using a static equilibrium method and solution calorimetry at atmospheric pressure, respectively. In addition, densities of FPEA in the two solvents at a diluted region were accurately measured for compositional analysis of equilibrium samples. Meanwhile, we explored the thermal stability of solid FPEA by using thermogravimetry. Crystalline FPEA was thermal stable blow 378.15 K and its molar heat capacity increased from 42.2 to 119.7 J·mol−1·K−1 when heated from 308.15 to 363.15 K, as determined by differential scanning calorimetry. When FPEA was further heated, it started to decompose at around 453.15 K without prior melting and then continued to decompose in several steps with the subsequent increase of temperature. When it was dissolved in the two solvents, endothermic effect was observed and the molar enthalpy of dissolution FPEA in ethanol at infinite dilution was about 2 kJ/mol higher than that in water, suggesting more hydrogen bond formation in water. The molality solubility of FPEA in water was generally higher than that in ethanol, but the difference decreased significantly with the increase of temperature. From 347.15 down to 279.15 K, the solubility in water decreased from 1.292 to 0.237 mol·kg−1, while that in ethanol decreased from 1.247 to 0.084 mol·kg−1, which justified the suitableness of using ethanol as the solvent for the cooling crystallization of FPEA with respect to product yield. The thermodynamic functions of solubility and solvation processes were estimated. An integrated approach by van't Hoff plot, enthalpy-entropy compensation analysis and solution calorimetry showed that enthalpy-entropy compensation was occurring in the dissolution of FPEA in both solvents and the enthalpic effect dominantly controlled the Gibbs free energy change of the process.

The Co-60 radiation ground simulation test was conducted on the Mechanical property of polyimide film, thermo gravimetric and XPS was used to analyze the evolution mechanism of polyimide film in different dosages. It was found that the mechanical properties such as tensile force, tensile strength and rupture elongation of polyimide film in gamma ray radiation increase firstly and then exponent decrease. The corresponding initial decomposition temperature of the gamma ray-radiated polyimide film changed from 570°C to 590°C for weight-loss ratio of 2%. From XPS analysis, it can be found that there were rupture and crosslink of chemical bond in polyimide film. In early stage of gamma ray radiation, the rupture of C-N bond and following crosslink is for the increase of mechanical properties of polyimide film, and as the increase of radiation, the rupture of C=O and –N(CO) bond, formation of C-N bond, release of N was for the decrease of mechanical properties of polyimide films.

The deuterium lamp was used as simulation source to study the Mechanical property of polyimide film in space far ultraviolet environment, thermo gravimetric and XPS was used to analyze the evolution mechanism of polyimide film in different exposures. It was found that the mechanical properties such as tensile strength and rupture elongation of polyimide film decrease firstly and then exponent increase until to stable. From XPS analysis, it can be found that there were rupture and crosslink of chemical bond in polyimide film. In early stage of far ultraviolet radiation, the rupture of C-N, C=O, C-O, C-C bond is for the decrease of mechanical properties of polyimide film, and as the increase of far ultraviolet exposure, the release of N, and formation of C-N bond is for the increase of mechanical properties of polyimide film.

In this work, polymeric ionic liquids (PILs) based on imidazolium ionic liquid monomer, which possessed hierarchical porous structure and rich Lewis basic sites, could effectively adsorb both large-sized and small molecular phenolic compounds from aqueous solution. The maximum adsorption capacities of the as-synthesized PILs for tannic acid (TA), 4-nitrophenol (4-NP) and 4-chlorophenol (4-CP) reached as high as 911 mg/g, 460 mg/g and 433 mg/g, respectively. The capacity for TA was the highest among the existing adsorbents. The abundant Lewis basic sites (N-atom and Cl−) provided by imidazolium ionic liquids and the special hierarchical porous structure of PILs were responsible for its excellent phenolic adsorption performance. The adsorption equilibrium data of 4-NP and 4-CP fitted well with the Freundlich model while those of TA complied better with the Langmuir model. The mechanism analysis indicated that the adsorption for 4-NP and 4-CP was mainly due to π–π interactions, and that for TA was dominated by H-bonding and electrostatic interaction. The PILs could be easily regenerated. This study provided a novel material for the treatment of phenolic wastewater.

Recovery of fluorine from wet-process phosphoric acid (WPA) to produce ammonium fluoride (NH4F) and sodium fluoride (NaF) provides an environmentally-friendly route to purify WPA and produce high value-added fluoride salt. The solubility data and the related electrolyte thermodynamics are essential for a rational separation design of pure NH4F from aqueous NaF solution by crystallization. In this contribution, the solubilities of NH4F in aqueous NaF solutions of different concentrations from dilute to saturated were systematically measured at 298.15 K using a dynamic synthesis method. Experimental results show that the presence of NaF in the solution could significantly decrease the solubility of NH4F due to the common-ion effect which was decreased by 72.4% when the molality of NaF was only around 0.015 mol/kg. The data can be used to determine the yield of NH4F and liquid composition in the vacuum evaporative crystallization of NH4F. The mean activity coefficients of NH4F at saturation were determined from the experimental solubility data and then correlated with the extended Debye-Hukel equation and the Pitzer model. With four adjustable parameters, both models are able to accurately calculate the experimental data over a wide range of salt concentrations. The average relative deviations between the experimental and calculated logarithm of mean activity coefficients of NH4F from the two models are 1.43% and 2.29%, respectively. The binary and ternary ionic parameters for the Pitzer model are found to be concentration dependent and the correlations of them as functions of ionic strength are proposed.

The solubility of m-phthalic acid has been measured in co-solvent mixtures conformed by acetone and ethanol over the entire solvent composition and in the temperature range of (278–323) K. Experimental results showed that the solubility always increased with increasing temperature in the binary solvent mixtures with constant solvent composition, indicating the endothermic character of the dissolution process. The solubility data was well correlated by semi-empirical regression models of the van't Hoff and the λh equations with average relative deviation (ARD) of 1.02% and 2.79%, respectively. Apparent deviation from the van't Hoff plot on solubility was observed but no polymorphic change of m-phthalic acid was found, implying the decisive influence of the change in the solvent molecular structure and the solvent-solvent interactions with temperature. On a solvent composition basis, the solubility in the co-solvent mixtures is clearly higher than that in both pure ethanol and acetone with the maximum appearing at acetone mole fraction in between 0.3 and 0.4, depending on the dipolarity/polarizability of the mixed solvents. On the other hand, m-phthalic acid exhibited reduced solubility when small amount of ethanol is added into acetone at temperatures above 315 K. The Simplified Modified Wilson (SMW) model was adopted to reproduce the isothermal solubility data over the entire acetone composition and the obtained overall ARD was 3.50%, with which the exact maximum solubility and the corresponding solvent composition at different temperatures were calculated.

Densities of binary mixtures of formic acid + methanol and formic acid + water, including those of pure liquids, are measured over the entire composition range at temperature from 288.15 to 323.13 K and at atmospheric pressure. The comparison of experimental data with literature values shows quite good agreement. Volumetric properties of the excess molar volume, partial molar volumes and excess partial molar volumes are obtained from the experimental density data and the Redlich–Kister polynomial equation correlations. The obtained results are interpreted by the strong intermolecular attractive interactions and the formation of new hydrogen bonded complex between the two polar liquid molecules.

In this paper, space environments and effects are briefly introduced firstly, and then the demand of a general light integrated exploration on the space environment and effects are analyzed. Thirdly, on the basis of the analysis on foreign integrated detection device for the space environment and effects, the scheme of general lightweight integrated detection for space environment and effect in China was presented. At last, some key technologies, such as overall design, system integration, data acquisition and analysis, ground calibration and verification, spatial environment adaptability evaluation and so on, are put forward.

A basic catalyst for urea alcoholysis to propylene carbonate (PC) was prepared from a solid waste, phosphate tailing (PT), and was characterized by TGA, BET, XRD, CO2-TPD and EDS. The PC yield was found to be related to the total content of Mg, Ca and P elements and strong basic sites on the catalyst surface. PT-800-4 possessed the highest total content, which led to the formation of strong basic sites and the highest PC yield of 81.8% with the 95.6% selectivity at the catalyst amount of 0.22 wt% (based on urea), and could be reused at least 5 times.

Spacecraft in orbit will encounter space radiation environments such as electron, proton, heavy ions, gamma ray, etc; and results in the space radiation effects such as single event effects, total ionizing dose effects, displacement damage effects, surface charging and discharging or electrostatic discharging, internal charging effects. So protection from space radiation should be given to the spacecraft. The protection principle and validity from space environments on spacecraft is introduced firstly, and then mass shielding material, ESD protection material, and radiation hardening functional material, were discussed. At last, some development directions on protection material from space radiation environments are proposed.

Quaternary Pd substituted MgNi-based hydrogen storage alloys Mg 0.9− x Ti 0.1 Pd x Ni ( x = 0.04, 0.06, 0.08, 0.1) in amorphous phase were prepared by mechanical alloying (MA). They exhibited enhanced cycle life in our previous studies. However, their electrochemical impedances and its relationship with electrode reaction kinetics are still unclear. In this work, the impedance spectra of the above electrode alloys were measured at different depths of discharge (DODs). The observed spectra were fit well with the equivalent circuit model used in the paper. We further observed that the rate-determining step changed from charge-transfer to hydrogen diffusion with proceeding of discharge according to the fitting analyses of spectra. The fitted results demonstrated that charge-transfer resistance R ct decreased and then increased with the depth of discharge (DOD) and it also increased with Pd content among the studied alloys. Thickness of surface passive film, which is proportional to the reciprocal of double layer capacitance near the electrode alloy surface according to Badawy et al., increased with the DOD and especially with Pd content in the alloys. Meanwhile, the thickened film on the surface of electrode alloys ensured its long cycle life. Through Randles plotting and comparing the variation of Warburg coefficient σ vs. DOD for the electrode alloys, it was found that σ increased with the DOD and substitution of Pd also improved the diffusion performance of the studied electrode alloys.