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BackgroundHyperuricemia increases the risk of gout and cardiovascular complications. Studys show that Chinese medicine can decrease uric acid through multiple targets, but many of these studys is conducted on animal, because the lack of a consistent prescription and mechanism.So we design this research to study whether Chinese medicine is really effective and which target is essential.MethodsThis study is a prospective, double-blinded, randomized, placebo controlled clinical trial. From March 2020 to December 2021.30 asymptomatic hyperuricemia people will be recruiting and assigned to either Chinese medicine group or placebo group, each group will have 15 subjects.During the 12-week observation period,there will be 4 times of visits.The decline in the uric acid is the main outcome measure, urinary uric acid,inflammatory biomarkers and other index that may involve in lowing uric acid are the secondary outcome measures.DiscussionThis study will probe the effect of Chinese medicine treatment on hyperuricemia, and explore possible therapeutic mechanisms. By performing this trial,we hoping to provide evidence and data to support further large clinical studies.Trial registration:ChiCTR2000038575. Registered on September 24, 2020.

The research has revealed the problem of sulfur dioxide emissions during the coal combustion. Combustion experiments were made for Shanxi coal at 1000oC. Red mud, carbide and shell powder were chosen as the primary sulfur-fixing agent. Through the experiment, the best ratio of Ca/S is 2.0 at 1000oC. When the ratio of red mud, carbide and shell powder were 50%, 15% and 35%, the maximum sulfur-fixing efficiency was 76.05%. Orthogonal experimental results showed that the best additive formula was 9% of Fe2O3, 5% of Na2CO3, 5% of ZnO. The maximum sulfur-fixing efficiency reached 89.23%. In addition, it was made thermogravimetric analysis of coal with different additives. By contrast, samples with sulfur-fixing agent generated two-stage combustion significantly, ignition point increased. The amount of coal residues with sulfur-fixing agent and sulfur-fixing additives showed an increase in the quantitative analysis.

The most effective technology currently for flue gas denitrition is selective catalytic reduction (SCR). And the major problem against spreading SCR technology is the high cost and low efficiency of the catalyst for SCR. Al2O3 supported Mn-Fe oxide precursor was prepared through water/ethanol coprecipitation and then nitridized through NH3-TPD. Thus the inexpensive and efficient Mn-Fe-O-N/Al2O3 catalyst was obtained. The catalyst with a Mn/Al molar ratio of 0.4 and a Fe loading of 6.0 wt.% was testified to have the best performance for denitrition. The NOx conversion reached 95% at low temperature (150~200°C).

The prepared Mn-Ce/CNTs catalyst was tested with Temperature-Programmed Desorption (TPD) in this experiment. The adsorption – desorption of NO, NH3, O2on the surface of catalyst were studied and the mechanism of SCR was analyzed. The conclusions were as follows: NH3was easily absorbed on the surface of Mn-Ce/CNTs catalyst for its significant competitive advantage; it can restrain the absorption of NO. The adsorption performance of NH3on catalyst surface was far greater than NO. When NO, O2adsorbed on the catalyst at the same time, the desorption amount of NO from catalyst significantly was less than the NO absorbed only. This shows that the O2can promote the adsorption of NO on the catalyst in SCR system.

The metal oxide catalyst was prepared by loading MnxOyon carbon nanotubes (CNTs) with impregnation method. Then the catalyst was characterized by BET, TEM and XPS, and the catalytic activity of the catalyst for selective catalytic reduction (SCR) of NO at low-temperature was investigated. The results showed that the species of active components loaded on the catalyst were MnO2and Mn2O3. The NO conversion was improved with reduction temperature increase under 250°C, increased slowly over 250°C. The O2content had an outstanding effect on NO conversion of catalysts at a low concentration range. Once the oxygen content was enhanced over 5%, there was no significant increase in the NO conversion. With the increasing of space velocity, the NO conversion rate was decreased under the reaction conditions.

In this paper the effects of compound sulfur-fixing agents and compound additives on the sulfur-fixing efficiency were discussed. Thermogravimetric Analysis was used to study the influence of sulfur-fixing agent and additives on the combustion performance. Besides, X-ray fluorescence was applied to research sulfur-fixing mechanism. The results show that, the best sulfur-fixing efficiency was 78.95%, when the ratio of Ca/S was 2.0, experimental temperature was 1000°C, burning time was 20min, the compound sulfur-fixing agents were 80% carbide slag and 20% wastes, the compound additives were 2% iron additives, 6% aluminum additives, 4% sodium additives, 5% silicon additives. The effects of the four additives on the sulfur-fixing efficiency were Al＞Fe＞Si＞Na.

The graphite oxide was synthesized with Hummers liquid-phase oxidation method in experiment, and then was reduced to graphene by sodium borohydride, the iron oxide was loaded by dipping method. The catalyst that made reacted in SCR reaction unit in laboratory, the catalysis properties of catalyst was investigated. The experiment results showed that graphene was flake nanometer sheet and presented transparent fold shape, its crystal structure was in order arrangement; the nature of graphene was close to that of raw graphite; their surface function groups were similar; Fe/graphene SCR catalysts had certain catalytic ability in the reaction, the NO conversion rate of catalyst was about 50% while the temperature range was from 200°C to 300°C.

Coke fines and semi-cokes have high ash content, low specific surface area and pore volume. In order to increase the properties of the sample and make the activated composite materials, it must be deashed and activated. In this research, the deashing experiment of the raw materials by different concentration of HNO3 and KOH was tested, then the material was activated in high temperature steam. From the FTIR test, we can acquire the content of the surface functional groups, such as carboxyl and hydroxyl. The specific surface area, pore size, volume of the material were determinated by using the N2 isothermal adsorption. From the experiments of acid and alkali treatment, we can conclude that the optimal technological condition of the material: the concentration 20% of alkali and acid treatment processing. The ash content is decreased to 8%. The acid functional groups increased rapidly after HNO3 treatment. The activated coke fines have mainly mesopores and its proportion of microspore is low. The specific surface area of the activated material reached 80m2/g and increased about 5 times than that of raw materials.

By comparing two kinds of coal in the preparation of activated carbon, Shenmu coal and Shenmu low ash coal, this paper discussed the advantages of low ash coal in preparing activated carbon, as well as the influence of the carbonization temperature, the activation temperature, the activation time, and the steam flow on the performance of coal activated carbon. Key words: activated carbon, ash content, iodine value, pore structure

This paper studied experimental conditions of making higher absorption activated carbon from Jincheng anthracite. The result was obtained by using the orthogonal experiment in which four factors were designated: the carbonization temperature, the carbonization time, the activation time as well as the additive types, with the target of iodine value. The optimized parameters had been found out: the carbonization temperature is 600 °C，the carbonization time is 1.5 h, the activation time is 4 h and the additive is NaNO3 which is better in a weight proportion of 8 %. At last, under the optimized parameters, the better activated carbon products could be gained by acid pickling, which has a higher iodine value 1094.8 mg/g and low ash content 8.73 %.

The optimal preparation condition of V2O5/TiO2 catalyst was investigated by the orthogonal experimental method. Five factors were chosen including A(molar ratio of NH4VO3 to oxalic acid),B(aging time of solution),C(active component content),D(impregnation temperature) and E(impregnation time). Every factor had four levels. The levels of A were1:2, 1:1, 3:2 and 2:1. The levels of B were 12h, 14h, 16h and 18h. The levels of C were 2%, 4%, 6% and 8%. The levels of D were 45°C, 55°C, 65°C, 75°C. The levels of E were 2h, 3h, 4h and 5h.The orthogonal experiment table was L16(45). Then the de-NOx rate of V2O5/TiO2 catalysts was tested in SCR catalytic reactor. The results showed that the influence of chosen factors decreased in the following order: C> B> E> D> A. The optimal plan of preparation experiments, obtained from the orthogonal experiment, is C3B1E3D3A4. So the optimal condition of preparation experiments are that active component content is 6%，aging time of solution is 12h，impregnation time is 4h，impregnation temperature is 65°C，molar ratio of ammonium metavanadate and oxalic acid is 2:1.

The novel Fe-Mn-Ti compound catalysts were prepared by co-precipitation, based on the lower price and smaller surface area TiO 2 . Then the cause of high catalytic activity which was represented by the compound catalyst was discussed. X-ray diffraction (XRD) was used to characterize the active phase and its results showed that a new Fe 0.33 Mn 0.05 Ti 2.52 O 5 phase was generated for Fe-MnO X -Ti. The Fe 0.33 Mn 0.05 Ti 2.52 O 5 played a decisive role on the process of low-temperature SCR. However the effect of catalyst was not observed when the temperature was up to nearly 300°C. Based on the above statement, above 90% conversion of NO X on the Fe(0.5)-MnO X -Ti(400) (the molar ratio of n(Fe)/[n(Fe)+n (Mn)]=0.5 and calcined at 400°C) was achieved among 180°C to 280°C.