Study on Influencing Factors of Methane Production Efficiency of Microbial Electrolytic Cell with CO_(2) as Carbon Source

Reducing CO_(2) to produce methane through microbial electrolytic cell(MEC)is one of the important methods of CO_(2) resource utilization.In view of the problem of low methanogenesis rate and weak CO_(2) conversion rate in the reduction process,theflowfield environment of the cathode chamber is changed by changing the upper gas cir-culation rate and the lower liquid circulation rate of the cathode chamber to explore the impact on the reactor startup and operation and products.The results showed that under certain conditions,the CO_(2) consumption and methane production rate could be increased by changing the upper gas recirculation rate alone,but the increase effect was not obvious,but the by-product hydrogen production decreased significantly.Changing the lower liquid circulation rate alone can effectively promote the growth of biofilm,and change the properties of biofilm at the later stage of the experiment,with the peak current density increased by 16%;The methanogenic rate decreased from the peak value of 0.561 to 0.3 mmol/d,and the CO_(2) consumption did not change signifi-cantly,which indicated that CO_(2) was converted into other organic substances instead of methane.The data after coupling the upper gas circulation rate with the lower liquid circulation rate is similar to that of only changing the lower liquid circulation rate,but changing the upper gas circulation rate can alleviate the decline of methane pro-duction rate caused by the change of biofilm properties,which not only improves the current density,but also increases the methane production rate by 0.05 mmol/d in the stable period.This study can provide theoretical and technical support for the industrial application scenario offlowfield regulation intervention of microbial elec-trolytic cell methanogenesis.

Effects of CaO and Na2CO3 on the Reduction of High Silicon Iron Ores

The effects of CaO and Na2CO3 on the reduction of high silicon iron ores at 1 250 ℃ were studied. The experimental results showed that the metallization rate was significantly hindered by the addition of CaO and Na2CO3, particularly at the early stage of roasting, compared to the rate without additives. In the absence of additives, iron oxides were quickly reduced to metallic iron, and fayalite was difficult to form. When CaO and Na2CO3 were added, the low reducible iron-containing silicate compounds formed and melted, subsequently retarding the metallization process. The inhibition of Na2CO3 was more noticeable than that of CaO, and higher Na2CO3 doses resulted in stronger inhibition of the increased metallization rate. However, when Na2CO3 was added prior to CaO, the liquid phase formed, which facilitated the growth of the metallic phase. To reinforce the separation of the metallic phase and slag, an appropriate amount of liquid phase generated during the reduction is necessary. It was shown that when 10% CaO and 10% Na2CO3 were added, a high metallization rate and larger metallic iron particles were obtained, thus further decreasing the required Na2CO3 dosage.

Effects of Biomineral Liquid from Spartina alterniflora on Growth,Body Color and Nutritional Components of Ricefield Eels,Monopterus albus

[Objective]The paper was to develop new fodder additives and to strengthen comprehensive utilization of Spartina alterniflora resources.[Method]The effects of biomineral liquid from S.alterniflora on growth,nutritional components of ricefield eels were studied.[Result]（1）0.5%of biomineral liquid had significant effect on weight gain rate,which was 8.37%higher than that in control group（P〈0.01）.Further supply of biomineral liquid could not increase the weight gain rate.Furthermore,biomineral liquid had no effect on the survival rate of ricefield eels.（2）Ricefield eels had certain changes in body color in the0.5%biomineral liquid group,and some ricefield eels were yellowing.（3）The contents of Cr,Fe,Zn in body of ricefield eels in treatment group were significantly higher than that in control group,but was lower than that in wild eel group,and the content of Se in treatment group was lower than that in control group and wild group（P〈0.01）.（4）The contents of K,Mg in muscle of ricefield eels in treatment group were higher than those in control group and wild eel group.The contents of ash and Ca in treatment group were close to that in control group but were higher than that in wild eel group.The content of crude fat in treatment group was close to that in wild eel group but was lower than that in control group.The contents of Zn,Se,Ni in treatment group were higher than that in control group and wild eel group,and the contents of Cr,Fe,Cu were close to that in control group and were higher than that in wild eel group（P〈0.01）.No significant differences were observed in the contents of moisture,crude fat and P among the three groups（P〉0.05）.[Conclusion]Addition of biomineral liquid from S.alterniflora could speed up the growth of ricefield eels and significantly improve their flesh quality,but had no significant effect on survival rate of ricefield eels.

Prevention and Treatment Test of Piglet Diarrhea

[Objective] The paper was to observe the clinical effects of compound Chinese traditional preparation Shenwudi oral liquid on prevention and treatment of piglet diarrhea, and to explore the diarrhea prevention and growth promotion effect of Shenwudi power on weaned piglets as the medical feed additive. [Method] Diarrhea piglets were randomly grouped, and the clinical prevention and treatment effects of Shenwudi oral liquid were observed. Meantime, the effects of Huangzhi oral liquid and levofloxacin mesylate and sodium chloride injection were determined and compared with that of Shenwudi oral liquid. Shenwudi powder was added into the specific feed of weaned piglets at the dose of 5 g/kg, to observe its diarrhea prevention and growth promotion effect on weaned piglets. Compound amoxicillin powder was added in drug control group at the dose of 0.3 g/kg; no drug was added in blank control group. [Result] The cure rate of sucking piglets by Shenwudi oral liquid was 88.57%, and its protection rate was 100%; the cure rate of weaned piglets by Shenwudi oral liquid was 90.00%, and the total effective rate was 95.00%; the protection rate of weaned piglet diarrhea by Shenwudi powder mixing feed was 100%, and the average daily feed intake on the 42^（nd） day was extremely higher than the blank control group（P〈0.01）. [Conclusion] Shenwudi oral liquid can be used for prevention and treatment of sucking piglet diarrhea.Meantime, Shenwudi mixing feed has good prevention effect and significant growth promotion effect on weaned piglet diarrhea.

Effect of herbal formula Xiao Pi-II on functional dyspepsia

OBJECTIVE: To investigate the therapeutic effect of the herbal medication Xiao Pi-II on the symptoms and gastric motility of patients with functional dysepsia (FD). METHODS: A total of 180 FD patients were divided randomly and equally into Xiao Pi-II and mosapride groups. The two groups were treated with Xiao Pi-II (100 mL, t.d.s., ante cibum) and mosapride (5 mg, t. d.s., ante cibum) for 2 weeks. Before treatment and 3 days after all medication was stopped, patients responded to a questionnaire evaluating gastrointestinal symptoms and were assessed with abdominal three dimensional ultrasonography (3D-US) for gastric motility. RESULTS: Gastrointestinal symptoms (especially bloating, post-prandial fullness and eructation) were improved significantly in FD patients treated with Xiao Pi-II (P<0.05, P<0.05, and P<0.05), but no significant difference was found in the mosapride group (P>0.05). The effective rates in the Xiao Pi-II and mosapride group were 86.7% and 60.0%, respectively (P<0.05). The gastric liquid emptyingrate (GLER) in the Xiao Pi-II group showed a significant increase (P<0.01) after 2 weeks of treatment but there was no significant change (P>0.05) of GLER in the mosapride group. CONCLUSION: Compared with mosapride, Xiao Pi-II improved symptoms and GLER significantly in FD patients with delayed gastric emptying.

Circulating fluidized bed biological reactor for nutrients removal

A new biological nitrogen removal process,which is named herein“The circulating fluidized bed bio-reactor(CFBBR)”,was developed for simultancous removal of nitrogen and organic matter.This process was composed of an anaerobic bed(Riser),aerobic bed(Downer)and connecting device.Influent and nitrified liquid from the acrobic bed enters the anaerobic bed from the bottom of the anaerobic bed,completing the removal of nitrogen and organic matter.The system performance under the conditions of different inflow loadings and nitrified liquid recirculation rates ranging from 200% to 600% was examined.From a technical and economic point of view,the optimum nitrifed liquid recirculation rate was 400%.With a shortest total retention time of 2.5 h(0.8 h in the anaerobic bed and 1.5 h in the aerobic bed)and a nitified liquid rocir-culation rate of 400% based on the influent flow rate,the average removal efficiencies of total nitrogen(TN)and sol-uble chemical oxygen demand(SCOD)were found to be 88% and 95%,respectively.The average efluent concentra-tions of TN and SCOD were 3.5 mg/L and 16 mg/L,respoctively.The volatile suspended solid(VSS)concentra-tion,nitrifcation rate and denitrification rate in the system were less than 1.0 g/L,0.0260.1 g NH_(4)^(+)-Ng VSS-d,and 0.016-0.074g NO_(x)^(-)-Ng VSS-d,respectively.

Finite time thermodynamics analysis and research of pulsating heat pipe cold storage device

Phase change energy storage technology can effectively solve the energy mismatch in space and time.There are many disadvantages of phase change materials(PCMs),such as high supercooling,phase separation and poor heat transfer performance.As a new type of heat exchange structure,pulsating heat pipe has the advantages of simple structure,high heat transfer coefficient and good economic behavior.The system efficiency can be greatly improved by using pulsating heat pipe combined with cold storage technology.A set of pulsating heat pipe type cold storage device is developed,the finite time thermodynamic analysis is carried out,and the correlation between heat pipe efficiency and power is established.The three-dimensional physical model of pulsating heat pipe is simulated and verified by experiments.The experimental results show that in the cold storage stage,with the increase of the filling rate,the greater the pressure is,the better the heat transfer effect is;in the cold release stage,with the decrease of the filling rate,the smaller the pressure is,the better the heat transfer effect is.