Biodiesel production from microbial lipid obtained by intermittent feeding of municipal sludge and treated crude glycerol

In the present study,municipal secondary sludge and purified glycerol(obtained after acid treatment of crude glycerol)were used together for lipid production using intermittent feeding strategy.Intermittent sludge feeding strategy(sludge SS 30 g/L)resulted in a higher biomass(54.99 g/L)and lipid concentration(25.35 g/L)at 96 h when compared to 35 g/L SS single sludge feeding or control strategy(45.67 g/L biomass&19.16 g/L lipid).Moreover,the intermittent sludge feeding strategy significantly reduced foaming and requirement of anti-foam during fermentation when compared to control strategy.The energy balance of biodiesel production from lipid obtained by intermittent sludge feeding strategy(30 g/L SS)was energeti-cally favorable.It was also revealed from yield coefficients and energy balance that sludge had an important contribution in microbial lipid and biodiesel production.

EXPERIMENTAL RESEARCH ON SLOTTED & PERFORATED ELECTROPLATED CBN GRINDING WHEEL WITH RADIAL JET

A creative conception is proposed to enhance heat transfer in grinding contact zone through jet impinging on the basis of analysis on the mechanism of burn during creep feed grinding, and a new apparatus of slotted & perforated electroplated CBN grinding wheel with radial jet is developed, the effect on heat transfer is studied through the experiment of intermitted creep feed grinding. Experimental results show that the technology of enhancing heat transfer through jet impinging is valid to raise the efficiency of heat transfer in grinding contact zone and it is widely applied to solve the problem in grinding burn for difficult to machine materials.

Restricted feeding regimens improve white striping associated muscular defects in broiler chickens

The current study investigated the effects of intermittent feeding(IF)and fasting strategies at different times post–hatch on muscle growth and white striping(WS)breast development.In the first trial,32 one-day-old Abor Acre broilers were fed ad libitum(AL)for 3 d post–hatch and then randomly allotted into 4 feeding strategies including AL,1h-IF group(1 h IF,4 times feeding/d,1 h each time),1.5h-IF(1.5 h IF,4 times feeding/d,1.5 h each time),and fasting(1d acute fasting,6 d free access to feed)groups and fed for 7 d.Although angiogenic genes including VEGFA,VEGFR1,and VEGFR2,and myogenic genes including MYOG and MYOD were upregulated(P<0.05),the breast muscle satellite cell(SC)number and PAX7,MYF5 expression were decreased by the IF strategies(P<0.05).One-day fasting at 6 d of age also upregulated angiogenic genes and MYOD expression(P<0.05),downregulated MYF5 expression(P<0.05),but did not change SC number(P>0.05).In the second trial,384 one-day-old birds were fed AL for 1 wk and then randomly allotted to the above 4 feeding strategies starting at 8 d of age until 42 d of age.Similarly,IF and fasting strategies upregulated the expression of angiogenic and myogenic genes(P<0.05).Both 1h-IF and 1.5h-IF increased breast muscle SC number(P<0.05).At slaughter,breast muscle fiber diameter of 1.5h-IF was smaller but the SC number was larger than that of the birds fed AL(P<0.05).The IF and fasting strategies prevented WS development,and reduced breast WS scores and triglyceride content(P<0.05)without changing the body weight(P>0.05).Fasting and 1h-IF reduced the expression of adipogenic genes ZNF423 and PDGFRα(P<0.05).Moreover,IF and fasting strategies reduced fibrosis in breast muscle and reduced skeletal muscle-specific E3 ubiquitin ligases(TRIM63 and MAFBX)(P<0.05).Fasting significantly reduced CASPASE-3 in breast muscle(P<0.05).In conclusion,IF starting in the first week decreases SC number.Compared to AL,IF or fasting promotes muscular angiogenesis,increases SC number,prevents muscle degeneration,and prevents the development of WS without impairing the growth performance of broiler chickens.