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A two-year field experiment was carried out in a Cu-Zn-Cd-Pb-contaminated field with

An aqueous blend of 1-butyl-3-methylimidazolium tetrafluoroburate ([Bmim][BF4]) + piperazine (PZ) was proposed in this work. Density and viscosity of the aqueous blend were measured and correlated at (293.15–333.15) K and atmospheric pressure. Performance of CO2 absorption into the aqueous blend was evaluated. It turned out that PZ mass fraction slightly influenced on the density and viscosity, being linear with them. Temperature significantly affected the viscosity. The calculated values are in good agreement with the experimental values. The main factors affecting the CO2 loading of the aqueous blend were PZ mass fraction, gas CO2 mole fraction and temperature. The average absorption rate of the aqueous blend was the biggest in the aqueous [Bmim][BF4], PZ and [Bmim][BF4]/PZ, and much higher than that of the former two. The performance of the aqueous [Bmim][BF4]/PZ with low PZ mass fraction was better than that with high PZ mass fraction. It demonstrated that the aqueous blend of [Bmim][BF4]/PZ is a good absorbent of CO2.

Aqueous amines are the most commonly used CO2 absorbents. But they have many shortcomings such as volatile loss, thermal degradation, corrosivity and wetting on polymer membranes. Ionic liquids can avoid the shortcomings and show unique performances. Diethanolamine glycinate, a ionic liquid made of hydroxyl ammonium amino acid salt, was developed to capture CO2 for greenhouse gas emission reduction. In order to evaluate the ionic liquid performance, membrane flux, gas outlet CO2 concentration, appropriate ionic liquid concentration and operational parameters were investigated by membrane gas absorption. Membrane liquid desorption was tested for regeneration of diethanolamine glycinate. Performance of diethanolamine glycinate ionic liquid was also compared with that of glycinate and diethanolamine. Results show that diethanolamine glycinate ionic liquid had a higher membrane flux, e.g., 6.6 × 10−4 mol m−2 s−1, and a lower gas outlet CO2 concentration (yout/yin, e.g., 0.07) in membrane gas absorption. Changes in operational conditions, e.g., gas and liquid flowrates increase, changed the membrane flux of membrane gas absorption, which increased only by 23.9%. Dominant factors affecting the membrane flux were the gas CO2 mole fraction, increasing the flux by 80.0%, and the ionic liquid concentration, increasing the flux more than 2 times. The ionic liquid was much more easily regenerated and possessed large regeneration efficiency and average regeneration velocity. Diethanolamine glycinate ionic liquid is thus an efficient and promising CO2 absorbent.

A differential probe-fed liquid crystal (LC)-based frequency tunable circular-ring patch antenna is presented. Besides, cavity model is extended to analyze the LC-based antenna for the differential operation. According to the cavity model, the permittivity and loss tangent of the LC are extracted from the measured differential reflection coefficients. Acceptable agreements among the measurement, simulation, and calculation for differential impedances, reflection coefficients, and radiation patterns are obtained and also validate the extraction method and model. More importantly, the extended cavity model can provide a deep physical insight into the LC-based antenna.

An amino acid-functionalized protic ionic liquid (IL), monoethanolamine glycinate ([MEA][GLY]), was used as a CO2 absorbent. Its performance was evaluated by a membrane gas absorption (MGA) process. Various effect factors including both absorbent aspect and operational parameters were investigated in MGA for CO2 capture. Performance of [MEA][GLY] IL was also compared with that of an amino acid salt and an amine. Liquid CO2 loading of the functional protic IL was the largest in three absorbents, presenting an order of [MEA][GLY]>PGLY>MEA. [MEA][GLY] IL obtained a high membrane flux and a low gas outlet CO2 concentration in MGA process. It could reach 3.25 × 10−4 mol m−2 s−1 of membrane flux. The IL could achieve higher initial and instantaneous membrane fluxes and the maximal membrane flux with a range of optimum concentration of 3.5–4.5 mol L−1. Change of operational parameters, especially gas CO2 mole fraction, can significantly affect and enhance the membrane flux of MGA on a limited scale. [MEA][GLY] IL is a more environmentally-friendly and efficient CO2 absorbent.

The oxidation of cyclohexane to cyclohexanone, cyclohexanol, and adipic acid, which are important raw materials in nylon industry, is still being challenged in conventional processes. Microreactors and gold catalysts are both widely researched areas at present, so an effort was made to make use of collaborative properties of both. In this study, stainless steel microcapillary coated with a supported nano-gold catalyst was prepared, characterized, and employed for the oxidation of cyclohexane. Under the temperature of 180 °C, residence time of 4 min, reaction pressure of 3 MPa and molar ratio of oxygen to cyclohexane of 0.3:1, the conversion of cyclohexane was 2.09%, with the selectivity of cyclohexanol, 29.37%; cyclohexanone, 39.89%; cyclohexyl hydroperoxide, 2.46%; and adipic acid, 18.87%. Experiments showed that stainless steel microcapillary coated with a supported nano-gold catalyst in cyclohexane oxidation is a feasible process; the reaction time is very short, and the process operation runs safely.

Extreme learning machine (ELM) has been applied in near infrared spectral analysis as a novel chemometric method which attracted the attentions of various researchers. However, the dimension of spectral data is usually very high while more hidden nodes should be incorporated in original ELM model for spectral data. Thus the problems of high dimension and high colinearity in the output matrix of hidden layer of ELM model are inevitable. The solutions obtained with the existing Moore-Penrose generalized inverse can be ill-conditional due to the high dimension and high colinearity in the hidden layer output matrix. This study aims to propose an improved ELM to build spectral regression model. The proposed method firstly uses extreme learning machine (ELM) to relate spectral variables to response variable; then the output of each hidden node are treated as new variables; VIP-SPLS ( improved stacked PLS based on variable importance in the projection) proposed by our group recently is used to build the regression model between those new variables and the response variable. In this paper, this method is called as improved ELM (iELM). VIP-SPLS model can fully utilize the output information of each hidden node and can effectively solve the problems of high dimension and high colineariy. At the same time, VIP-SPLS also has the advantage of model ensemble. Therefore, the performance of ELM model used for spectral data can be improved if the VIP-SPLS is incorporated to relate the hidden layer output matrix and response variable. The proposed method is applied to a commonly used benchmark NIR spectral data for evaluation. The results demonstrate that the precision improvement of iELM model is 29.06% to PLS model and 27.47% to original ELM model, respectively.

The size distribution of particulate was analyzed by the FA-3 9 stage sampler in Northern-suburb of Nanjing from January to November in 2014. First, the monitoring result from FA-3 was compared with the results of the same period obtained from a medium flow size grading sampler (KC-120H) and online monitoring instrument of the Environmental Protection Agency. The data correlation coefficients were all greater than 0.95. The fine particle concentration from FA-3 was lower by 13.9% and 16.6%, while PM

A blended solution as a CO 2 capture agent was composed of potassium citrate (PC) and 2-amino-2-methyl-1-propanol (AMP). Density, viscosity and surface tension of the blended solution were determined in the range of (293.15–323.15) K, respectively. Physical characteristics of the blended solution were discussed and compared with that of single component and other blended systems. Correlations were developed to predict the three physical properties of the blended solution. Results indicate that when overall concentration of the blended solution increases, quality of the solution increases to result in the increase of values of the three physical properties. The three physical properties decrease as both temperature and AMP molar ratio in the blended solution increase. Prediction values from the correlations and experimental values fit reasonably well. The correlations for the three physical properties can give extra data of the system of (PC + AMP) solution.

A protic ionic liquid (IL), diethanolamine glycinate ([DEA][GLY]), was synthesized and characterized. Its physical properties, including density, viscosity, surface tension, conductivity and refractive index, were determined. CO2 solubility in [DEA][GLY] IL was also measured. Performances of [DEA][GLY] IL in absorbing CO2 in a bubble column were evaluated. The synthesized [DEA][GLY] is an amino acid-functionalized IL with dual groups of ammonium and amino. There was a good CO2 solubility in the IL at room temperature and atmospheric pressure, much better than the traditional ILs. Pure and aqueous [DEA][GLY] ILs are good CO2 absorbents. CO2 partial pressure and IL concentration have a significant impact on their absorption performance. [DEA][GLY] had an obvious advantage over the conventional ILs for CO2 absorption.

A new amino acid-functionalized ionic liquid (IL), monoethanolamine glycinate ([MEA][GLY]), was synthesized and characterized. Its physical properties were measured, including density, viscosity, surface tension, conductivity, and refractive index. The solubility of CO2 in [MEA][GLY] was determined. The ability of [MEA][GLY] to absorb CO2 was evaluated. [MEA][GLY] with an active amino group exhibits representative physical properties of a functionalized IL. The solubility of CO2 in the IL is more than 0.5 mol CO2/mol IL at room temperature and atmospheric pressure. The [MEA][GLY] and aqueous [MEA][GLY] ILs are thus good absorbents of CO2. The CO2 partial pressure and [MEA][GLY] concentration have a significant impact on their absorption.