Preparation of Fine Spherical Particle Sized Ceria by Precipitation Method with Ammonium Bicarbonate

Fine spherical particle sized ceria (CeO_2) was prepared by homogeneous precipitation method with ammonium bicarbonate as precipitant. The prepared CeO_2 has the primary particle size of 10～50 nm when calcined between 400～700 ℃ analyzed by XRD and the aggregated particle size is about 300 nm measured by LASER particle sizer. SEM, TG-DTA and Zeta-potential analyzer were employed individually to study the morphology and the formation of CeO_2 product. It was found that excess NH_4NO_3 can serve as an sphericallization agent to prepare spherical CeO_2 powder by precipitation method.

Effect of Electrochemical Treatment in Aqueous Ammonium Bicarbonate on Surface Properties of PAN-based Carbon Fibers

The surface properties of PAN-based carbon fibers electrochemically treated in aqueous ammonium bicarbonate before and after treatment were characterized by X-ray photoelectron spectroscopy (XPS), atomic force microscopy (AFM) and Dynamic Contact Angle Analysis (DCAA). The results of characterization indicated that the oxygen and nitrogen contents in carbon fiber surface were significantly increased by electrochemical treatment, and amide groups was introduced onto it, which was related with the electrolyte. The AFM photographs illustrated that the roughness of the fiber surface was also increased. The wettibality of the fibers was improved after treatment because the surface energy especially the polar part of it was increased.

Removal of SO2 using ammonium bicarbonate aqueous solution as absorbent in a bubble column reactor

In this work, the removal of SO2 from gas mixture with air and SO2 by ammonium bicarbonate aqueous solution as absorbent was investigated experi- mentally in a bubble column reactor. The effects of the concentration of ammonium bicarbonate, the SO2 inlet concentration of gas phase and the gas flow rate on the removal rate of SO2 were studied. The results showed that the higher the SO2 inlet concentration and the gas flow rate, the shorter the lasting time of SO2 completely removed in gas outlet, and then the faster the decrease in the removal rate of SO2. The lasting time of SO2 completely removed in gas outlet increased with increasing ammonium bicarbonate concentration. During the process of SO2 absorption, there was a critical pH of solution. When the solution pH was less than the critical pH, it would sharply fall, resulting in a rapid decrease of the SO2 removal rate. A theoretical model for predicting the SO2 removal rate has been developed by taking the chemical enhancement and the sulfite concentration in the liquid phase into account simultaneously.

Ammonium Bicarbonate Reduction Route to Uniform Gold Nanoparticles and Their Applications in Catalysis and Surface-Enhanced Raman Scattering

A new protocol for the synthesis of nearly monodisperse gold nanoparticles with controllable size is described. The pathway is based on the reduction of AuCl4 by ammonium bicarbonate in the presence of sodium stearate under hydrothermal conditions. The particle sizes could be easily tuned by regulating the reaction conditions including precursor concentration, reaction temperature and growth time. A tentative explanation for the reduction and growth mechanism of uniform gold nanoparticles has been proposed. The as-prepared gold particles showed good catalytic activity for the reduction of 4-nitrophenol to 4-aminophenol by excess NaBH4, and a surface-enhanced Raman scattering （SERS） study suggested that the gold nanoparticles exhibited a high SERS effect on the probe molecule Rhodamine 6G.

Green and sustainably designed intercalation-type anodes for emerging lithium dual-ion batteries with high energy density

Lithium dual-ion batteries(LiDIBs)have attracted significant attention owing to the growing demand for modern anode materials with high energy density.Herein,rust encapsulated in graphite was achieved by utilizing ammonium bicarbonate(ABC)as a template,which resulted in mesoporous Fe3O4embedded in expanded carbon(Fe3O4@G(ABC))via simple ball milling followed by annealing.This self-assembly approach for graphite-encapsulated Fe3O4composites helps enhance the electrochemical performance,such as the cycling stability and superior rate stability(at 3 A/g),with improved conductivity in Li DIBs.Specifically,Fe3O4@G-1:4(ABC)and Fe3O4@G-1:6(ABC)anodes in a half-cell at 0.1 A/g delivered initial capacities of 1390.6 and 824.4 mA h g^(-1),respectively.The optimized anode(Fe3O4@G-1:4(ABC))coupled with the expanded graphite(EG)cathode in Li DIBs provided a substantial initial specific capacity of 260.9 mA h g^(-1)at 1 A/g and a specific capacity regain of 106.3 mA h g^(-1)(at 0.1 A/g)after 250 cycles,with a very high energy density of 387.9 Wh kg^(-1).The strategically designed Fe3O4@G accelerated Li-ion kinetics,alleviated the volume change,and provided an efficient conductive network with excellent mechanical flexibility,resulting in exceptional performance in Li DIBs.Various postmortem analyses of the anode and cathode(XRD,Raman,EDS,and XPS)are presented to explain the intercalation-type electrochemical mechanisms of Li DIBs.This study offers several advantages,including safety,low cost,sustainability,environmental friendliness,and high energy density.

Fate of Fertilizer Nitrogen Applied to Crops Grown on Fluvo-Aquic Soil in Huang-Huai-Hai Plain

The fate of urea-and ammonium bicarbonate (ABC)-nitrogen (N) applied by prevailing traditional techniques to winter wheat (Triticum aestivum L.) or maize (Zea mays L.) grown in the fields of Fluvo-aquic soil was investigated using 15N tracer-micro-plot technique. Results show that:(1) at maturity of wheat, N recovery in plants and N losses of urea and ABC applied at seeding in autumn were 31-39%, and 34-46%, respectively, while the corresponding figures for side-banding at 10 cm depth in early spring were 51-57%, and 5-12%; surface-broadcast of urea followed by irrigation at early spring was as efficient as the side-banding in improving N recovery in plants and reducing N loss, however, such technique was found less satisfactory with ABC. (2) At the maturity of maize, N recovery in the plants and N loss of urea and ABC sidebanded at seedling stage or prior to tasseling ranged from 23% to 57%, and 9% to 26%, respectively. (3) Either in Wheat or in maize experiment, the majority of residual fertilizer N in soil profile (0-60 cm) was in the form of biologically immobilized organic N, however, the contribution of ammonium fixation by clay minerals increased markedly with depth in soil profile. (4) Though the proportion of residual fertilizer N was generally highest in the top 20 cm soil layer, considerable reaidual N (mostly 6-11 % of the N applied) was found in 60-100 cm soil layers.

Ammonia Volatilization from Soils Fertilized with Different Nitrogen Type and Application Method in Germination and Early Seedling Stages from the Radish Field

Ammonia volatilization(AV) from basal fertilizer with different nitrogen(N) types and application methods was investigated by the ventilation method in germination and early seedling stages during radish growth seasons in 2014. Four N fertilizer types, urea(U), ammonium bicarbonate(AB), ammonia sulfate(AS), and controlled urea formaldehyde(CUF) were applied through 5 cm depth placement(I) and 10 cm depth placement(II). The results showed that the N fertilizer type was the main factor that caused AV loss in germination and early seedling stages from the radish field. The highest and the lowest cumulative AV losses in germination and early seedling stages from the radish fields were 33.23 and 11.21 N kg/hm^2 for the treatments of AB+I and CUF+II, respectively, accounting for 60.40 and 26.40% of the N application for each treatment. The 10 cm deep placement of N reduced AV rates and lagged the AV process, and CUF significantly reduced ammonia volatilization. The data showed that the suitable N fertilizer type and application method for basal fertilizer were CUF and deep placement, respectively.Therefore, fertilizing with proper N fertilizer types and methods should be the efficient measures to mitigate AV losses from the radish field and will alleviate environment problems.

Efficient production of hydrogen peroxide in microbial reverse-electrodialysis cells coupled with thermolytic solutions

H_(2)O_(2) was produced at an appreciable rate in microbial reverse-electrodialysis cells(MRCs)coupled with thermolytic solutions,which can simultaneously capture waste heat as electrical energy.To determine the optimal cathode and membrane stack configurations for H_(2)O_(2) production,different catalysts,catalyst loadings and numbers of membrane cell pairs were tested.Carbon black(CB)outperformed activated carbon(AC)for H_(2)O_(2) production,although AC showed higher catalytic activity for oxygen reduction.The optimum CB loading was 10 mg/cm^(2) in terms of both the H_(2)O_(2) production rate and power production.The optimum number of cell pairs was determined to be three based on a tradeoff between H_(2)O_(2) production and capital costs.A H_(2)O_(2) production rate as high as 0.99±0.10 mmol/(L·h)was achieved with 10 mg/cm^(2) CB loading and 3 cell pairs,where the H_(2)O_(2) recovery efficiency was 52±2%and the maximum power density was 780±37 mW/m^(2).Increasing the number of cell pairs to five resulted in an increase in maximum power density(980±21 mW/m^(2))but showed limited effects on H_(2)O_(2) production.These results indicated that MRCs can be an efficient method for sustainable H_(2)O_(2) production.

Boosting the direct conversion of NH4HCO3 electrolyte to syngas on Ag/Zn zeolitic imidazolate framework derived nitrogen-carbon skeleton

The electrochemical reduction of NH4HCO3 to syngas can bypass the high energy consumption of high-purity CO_(2)release and compression after the ammonia-based CO_(2)capture process.This technology has broad prospects in industrial applications and carbon neutrality.A zeolitic imidazolate framework-8 precursor was introduced with different Ag contents via colloid chemical synthesis.This material was carbonized at 1000℃to obtain AgZn zeolitic imidazolate framework derived nitrogen carbon catalysts,which were used for the first time for boosting the direct conversion of NH4HCO3 electrolyte to syngas.The AgZn zeolitic imidazolate framework derived nitrogen carbon catalyst with a Ag/Zn ratio of 0.5:1 achieved the highest CO Faradaic efficiency of 52.0%with a current density of 1.15 mA·cm^(−2)at−0.5 V,a H2/CO ratio of 1-2(−0.5 to−0.7 V),and a stable catalytic activity of more than 6 h.Its activity is comparable to that of the CO_(2)-saturated NH4HCO3 electrolyte.The highly discrete Ag-N_(x)and Zn-N_(x)nodes may have combined catalytic effects in the catalysts synthesized by appropriate Ag doping and sufficient carbonization.These nodes could increase active sites of catalysts,which is conducive to the transport and adsorption of reactant CO_(2)and the stability of*COOH intermediate,thus can improve the selectivity and catalytic activity of CO.

Research on desorption and regeneration of simulated decarbonization solution in the process of CO_2 capture using ammonia method

Study on desorption and regeneration of simulated decarbonization solution using ammonia method for CO2 capture was car- fled out in order to understand the feature of regeneration of decarbonization solution. The mechanisms about solution desorp- tion after decarbonization were introduced briefly. Under the atmospheric pressure and in the presence of nitrogen carrier gas, several effects related to desorption of simulated decarbonization solution were analyzed, such as temperature, solution con- centration, pH, loading capacity, etc. The results showed that the CO2 desorption percentage increased with the increases of temperature, solution concentration and loading capacity, but CO2 desorption percentage increased with the increasing of pH and then decreased.

Iron-catalyzed hydroaminocarbonylation of alkynes:Selective and efficient synthesis of primaryα,β-unsaturated amides

α,β-Unsaturated primary amides are important intermediates and building blocks in organic synthesis.Herein,we report a ligand-free iron-catalyzed hydroaminocarbonylation of alkynes using NH_(4)HCO_(3)as the ammonia source,enabling the highly efficient and regioselective synthesis of linearα,β-unsaturated primary amides.Various aromatic and aliphatic alkynes are transformed into the desired linearα,β-unsaturated primary amides in good to excellent yields.Further studies show that using NH_(4)HCO_(3)as the ammonia source is key to obtain good yields and selectivity.The utility of this route is demonstrated with the synthesis of linearα,β-unsaturated amides including vanilloid receptor-1 antagonist TRPV-1.

Experimental study on capturing CO_(2) greenhouse gas by mixture of ammonia and soil

This paper presents our study on removal of carbon dioxide(CO_(2)) greenhouse gas emissions by using the mixture of ammonia and soil.CO_(2) capture capacity using this method is 15%higher than the sum of ammonia chemical absorption capacity and soil physical adsorption capacity.Scanning electron microscopy(SEM)and Fourier transform infrared spectroscopy(FTIR)are utilized to study this synergism.The removal effect is not only reflected in ammonia chemical reaction with CO_(2).CO_(2) can also be absorbed by ammonium bicarbonate(NH_(4)HCO_(3)) crystal,which is the main component of the product,or wrapped in the pore of the crystal or packed in the gap between the crystal and the soil.CO_(2) can be permanently deposited as carbonated minerals in the subsoil earth layers.