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Chemical additives of magnesium chloride (MaC) and ferrous sulfate (FS) were investigated in sewage sludge composting. A treatment without chemical additive was used as the control group (CK). The effects of MaC and FS on ammonia (NH3) and greenhouse gases (CO2, N2O and CH4) emissions were evaluated. The results showed that the addition of MaC and FS promoted the degradation of organic matter and increased the ammonium concentration of the compost product. The maximum pH values decreased from 8.98 (CK) to 8.49 and 8.0 in MaC and FS treatments, respectively. In addition, the NH3 emission for the MaC and FS treatments reduced by 58.3 % and 82.9 %, respectively, whereas the methane (CH4) emission decreased by 22.9 % and 24.9 %, respectively. However, in FS treatment, the carbon dioxide (CO2) and nitrous oxide (N2O) emissions were higher than those in CK. Furthermore, the FS treatment exhibited lower germination index values (71.4 %) and higher electrical conductivity (6.62 mS/cm). Therefore, MaC is suggested as an additive for reducing greenhouse gas emission and conserving nitrogen during sewage sludge composting.

Bulking agents are particularly important for sewage sludge composting. In this study, reusable polypropylene packing (RPP) was mixed with sawdust to improve composting. The effect of the mix ratio of sawdust and RPP on the physicochemical characteristics, nitrogen transformation, and emissions of greenhouse gas (GHG) as well as differences in the germination index values was detected in a lab-scale composting experiment. The results showed that the unique use of RPP as a bulking agent increased the moisture content over 70%, which resulted in poorer porosity and a less efficient O2 utilization environment and thus suppressed the degradation of organic matter. The highest CH4 9275.8 mg and lowest CO2 202.6 g emissions were detected after 25 days of composting in the treatment with RPP used as a bulking agent. When the mixing ratio of sawdust and RPP was 1:1, the temperature, oxygen supply, and dissolved organic carbon degradation were improved. The NH3, N2O, and CH4 emissions were reduced by 32.2, 18.3, and 90.7% compared with a treatment with RPP as a unique bulking agent. The RPP had no effect on conserving nitrogen during sludge composting; the total nitrogen loss was reduced from 29.3 to 18.2% when sawdust was mixed with RPP in a ratio of 1:1. Therefore, mixing RPP and sawdust in the dry weight ratio of 1:1 (sawdust: RPP) can be potentially used for reducing composting cost and improving the sewage sludge composting by reducing the amount of sawdust mixed and mitigating GHG and NH3 emissions.

Foodborne nanoparticles (NPs) refer to the nanostructures generated during food processing, rather than the man-made nano-structural additives that are added to improve the property of food. In this research, discovery of fluorescent NPs in roasted pork was reported at different temperature of 180, 230, and 280 °C. The size of the pork NPs was in the range of 5.93-7.49 nm. The FTIR and XPS analysis showed that the NPs are made up of graphitic carbon (sp2) and carbon defects (sp3), with abundant hydroxyl and carbonyl groups on the surface. The Ussing chamber test clearly showed the pork NPs had permeability passing through intestine. Significant fluorescence quenching of NPs was observed in the digestion

Traditional composting processes must be conducted with a bulking agent to ensure adequate air space for aeration. The bulking agent and composting materials are always completely mixed. A novel layered structure was introduced in sewage sludge composting, in which no bulking agent was used and bamboo charcoal was used as a separating material. Three lab-scale composting reactors (A: sawdust and sludge; B: bamboo charcoal and sludge; and C: sawdust, bamboo charcoal, and sludge) were continuously operated for 29 days. Several physicochemical parameters were investigated to evaluate the feasibility of layered composting with bamboo charcoal. The results indicated that the maximum temperatures during the thermophilic stage in treatments A, B, and C were 51.4, 50.9, and 51 °C, respectively. Layered composting with bamboo charcoal decreased the pH of the thermophilic stage from 8.98 in A to 8.75 in C, and delayed the peaks by about 120 h. The degradation rates of dissolve organic carbon (DOC) and dissolved nitrogen (DN) were 75 and 71.5% in treatment B, respectively, which were significantly higher than those of control group A (60 and 59.1%, respectively). The total NH3 emissions of treatment C (2127.8 mg) were significantly lower than those of A (2522.8 mg). Our results suggested that layered composting using bamboo charcoal as a separating material could be an alternative strategy to the traditional composting method. Moreover, layered composting combined with sawdust could effectively reduce NH3 emissions and N loss.

Two unique hybrids based on Wells–Dawson polyoxometalates, [Cu(en)2(OH2)]2[{Cu(en)2}{As2WV2WVI16O61}]·6H2O (1) and (H2dap)[Cu(H2dap)(H2O)2][{Cu(dap)(H2O)2}{As2W17CuO61}]·5H2O (2) (en = ethylenediamine and 1,2-dap = 1,2-diaminopropane), have been synthesized hydrothermally by reaction of Na2WO4, NaAsO2 and CuCl2 with 1,2-dap or en, and further characterized by elemental analysis, infrared radiation (IR) spectrophotometry, ultraviolet (UV) spectroscopy, thermogravimetric analysis (TGA), X-ray photoelectron spectroscopy (XPS) and single crystal X-ray diffraction. In compounds 1 and 2, the emerging building blocks link into new one-dimensional (1D) chain-like Wells–Dawson architectures via two M–O–M (M = Cu/W) and O–Cu–O bridges, which are rarely observed among this arsenotungstate class. The 1D chain-like architectures further extend into 3D supramolecular frameworks through hydrogen bond interactions. They represent the first family of Dawson-type double-bridge arsenotungstate chains built from M–O–M and Cu–L linkers. Compounds 1 and 2 have exhibited electrocatalytic activity toward the reduction of nitrite. Adsorption experiments show that the compounds have the ability to selectively adsorb MB from binary mixed dye solutions (MB and MO and MB and RhB). These compounds still maintain their excellent stability and adsorption properties after several cycles.

Two novel Wells-Dawson polyoxometalate-based compounds, (H

Air path model of cabin for cooling module simulation for vehicle has been constructed according to the test, and the simulation results were compared with the test data to verify the authenticity of the module. This simulation model provides an effective platform for vehicle thermal management analysis. The module is used to simulate the different intake grills and to find how different grills affect the performances of the cooling module. The intake grill effect significantly influences the performance of airflow into the cabin.

Cooling-module simulation for the fuel cell car has been built according with CFD and KULI software. The simulation results are compared with the test data to verify the authenticity of the module. Based on 3D and 1D calculation of the module is done to analyze the effect on the performance of the cooling module for fuel cell car.

Cooling module simulation for vehicle has been built according to the heat balance test, and the simulation results are compared with the test data to verify the authenticity of the module. This simulation model provides an effective platform for vehicle thermal management analysis. Module is used to simulate the air conditioning running and to find how different ambient temperaturesto effect the performance of the cooling module. The air conditioning working and ambience temperaturewhichis significantly influence the performance of the cooling system.

The wind tunnel test dating for the cooling module in the vehicle conditions shows that the actual fan rotation is evidently different from the fan in bench test rotation. There is an intake high pressure zone. It is easy to conduct airflow into the cabin, and under the cabin, there is a negative pressure zone. It is easy to conduct airflow outside the cabin. Both of the different pressure zones affect the fan rotation. Air path of the cabin is divided into three different areas. Base on the parameters of CP BIR and-CP, the aerodynamic characteristics of the cabin build the cooling module under the vehicle working conditions. The model can predict the states of the fan working, when the target vehicle speed conditions are met, and it has important application value for the design of intelligent cooling module control system as well.