Dry corn straw(DCS)is usually used in anaerobic digestion(AD),but fresh corn straw(FCS)has been given less consideration.In this study,the thermophilic AD of single-substrate(FCS and DCS)and co-digestion(straw with ca...Dry corn straw(DCS)is usually used in anaerobic digestion(AD),but fresh corn straw(FCS)has been given less consideration.In this study,the thermophilic AD of single-substrate(FCS and DCS)and co-digestion(straw with cattle manure)were investigated.The results show that when FCS was used as the single-substrate for AD,the methane production was 144 mL·g^(−1)·VS^(−1),which was 7.5%and 19.6%higher than that of single DCS and FCS with cattle manure,respectively.In addition,the structure of FCS was loose and coarse,which was easier to be degraded than DCS.At the hydrolysis and acidification stages,Clostridium_sensu_stricto_1,Clostridium_sensu_stricto_7 and Sporosarcina promoted the decomposition of organic matter,leading to volatile fatty acids(VFAs)accumulation.Methanosarcina(54.4%)activated multifunctional methanogenic pathways to avoid the VFAs inhibition,which was important at the CH_(4) production stage.The main pathway was hydrogenotrophic methanogenesis,with genes encoding formylmethanofuran dehydrogenase(K00200-K00203)and tetrahydromethanopterin Smethyltransferase(K00577-K00584).Methanosarcina also activated acetotrophic and methylotrophic methanogenesis pathways,with genes encoding acetyl phosphate(K13788)and methyl-coenzyme M reductase(K04480,K14080 and K14081),respectively.In the co-digestion,the methanogenic potential of FCS was also confirmed.This provides a scientific basis for regulating AD of crop straw.展开更多
The object of this study was to determine the proper mixing ratio of fresh rice straw to corn steep liquor(CSL) to obtain a high protein content silage feed. The following experimental silages were generated: the cont...The object of this study was to determine the proper mixing ratio of fresh rice straw to corn steep liquor(CSL) to obtain a high protein content silage feed. The following experimental silages were generated: the control(C1), composed of fresh rice straw without CSL additive, mixed with CSL in the ratios of 4:1(C4),3:1(C3) and 2:1(C2). Lactic acid bacteria(LAB) inoculant was applied at the rate of 50 mL/kg(fresh basis)of forage to achieve a final application rate of 1 x 10~6 cfu/g of fresh matter(FM). Duplicate silos for each treatment were opened after 0,3, 7,10,20,30,45 and 60 d for microbiological and chemical analysis. The results showed that the addition of CSL significantly increased crude protein(CP) contents, and decreased neutral detergent fiber(NDF) and acid detergent fiber(ADF) contents of treatments after 60 d of ensiling(P < 0.05). The lactic acid contents in C4 and C3 were significantly higher than that in C1(P <0.05). In summary, mixing fresh rice straw with CSL at addition levels of 4:1(C4) and 3:1(C3) can improve the fermentation quality and nutrient composition of fresh rice straw silage. However, a large proportion of CSL(C3) had a negative impact on the aerobic stability of fresh rice straw.展开更多
以提取的玉米秸秆纤维素为原料制备羧甲基纤维素,在其中添加甘油和不同浓度的AgNO_(3)后制得改性复合膜。通过扫描电子显微镜(SEM)、X射线衍射(XRD)、X射线光电子能谱(XPS)、热重分析(TGA)、傅里叶红外光谱(FT-IR)对改性复合膜进行结构...以提取的玉米秸秆纤维素为原料制备羧甲基纤维素,在其中添加甘油和不同浓度的AgNO_(3)后制得改性复合膜。通过扫描电子显微镜(SEM)、X射线衍射(XRD)、X射线光电子能谱(XPS)、热重分析(TGA)、傅里叶红外光谱(FT-IR)对改性复合膜进行结构和形貌表征,结果表明:改性复合膜质地均匀,部分Ag^(+)以单质银的形式与膜中的成分相互作用,膜热稳定性良好,满足保鲜材料要求。改性复合膜对大肠杆菌(E.coli)及白色葡萄球菌(S.albus)的抑制情况进一步证明了其中存在单质Ag粒子,对S.albus的抑制能力更强。用改性复合膜包裹蓝莓,存储10 d后的失重率低于7%、颜色几乎没有变化;可溶性固形物损失小于3%、可滴定酸下降不明显,当加入1 mL 0.01 mol/LAgNO_(3)时,改性复合膜的保鲜性能相对较好。展开更多
基金supported by the Shaanxi Youth Thousand Talents Project(A279021901)the Scientific and Technological Activities for Overseas Researchers in Shaanxi Province(20200002)+3 种基金the Chinese Universities Scientific Fund(2452021112)the Key Research and Development Project of Shaanxi Province(2020NY-114)the Double first-class construction project funded by Northwest A&F University,Northwest A&F University Young Talent Project(Z111021902)the USA Energy Foundation(G-2206-33957).
文摘Dry corn straw(DCS)is usually used in anaerobic digestion(AD),but fresh corn straw(FCS)has been given less consideration.In this study,the thermophilic AD of single-substrate(FCS and DCS)and co-digestion(straw with cattle manure)were investigated.The results show that when FCS was used as the single-substrate for AD,the methane production was 144 mL·g^(−1)·VS^(−1),which was 7.5%and 19.6%higher than that of single DCS and FCS with cattle manure,respectively.In addition,the structure of FCS was loose and coarse,which was easier to be degraded than DCS.At the hydrolysis and acidification stages,Clostridium_sensu_stricto_1,Clostridium_sensu_stricto_7 and Sporosarcina promoted the decomposition of organic matter,leading to volatile fatty acids(VFAs)accumulation.Methanosarcina(54.4%)activated multifunctional methanogenic pathways to avoid the VFAs inhibition,which was important at the CH_(4) production stage.The main pathway was hydrogenotrophic methanogenesis,with genes encoding formylmethanofuran dehydrogenase(K00200-K00203)and tetrahydromethanopterin Smethyltransferase(K00577-K00584).Methanosarcina also activated acetotrophic and methylotrophic methanogenesis pathways,with genes encoding acetyl phosphate(K13788)and methyl-coenzyme M reductase(K04480,K14080 and K14081),respectively.In the co-digestion,the methanogenic potential of FCS was also confirmed.This provides a scientific basis for regulating AD of crop straw.
基金funded by the National Dairy Industry and Technology System project (CARS-37)of Agriculture Ministry in China
文摘The object of this study was to determine the proper mixing ratio of fresh rice straw to corn steep liquor(CSL) to obtain a high protein content silage feed. The following experimental silages were generated: the control(C1), composed of fresh rice straw without CSL additive, mixed with CSL in the ratios of 4:1(C4),3:1(C3) and 2:1(C2). Lactic acid bacteria(LAB) inoculant was applied at the rate of 50 mL/kg(fresh basis)of forage to achieve a final application rate of 1 x 10~6 cfu/g of fresh matter(FM). Duplicate silos for each treatment were opened after 0,3, 7,10,20,30,45 and 60 d for microbiological and chemical analysis. The results showed that the addition of CSL significantly increased crude protein(CP) contents, and decreased neutral detergent fiber(NDF) and acid detergent fiber(ADF) contents of treatments after 60 d of ensiling(P < 0.05). The lactic acid contents in C4 and C3 were significantly higher than that in C1(P <0.05). In summary, mixing fresh rice straw with CSL at addition levels of 4:1(C4) and 3:1(C3) can improve the fermentation quality and nutrient composition of fresh rice straw silage. However, a large proportion of CSL(C3) had a negative impact on the aerobic stability of fresh rice straw.
文摘以提取的玉米秸秆纤维素为原料制备羧甲基纤维素,在其中添加甘油和不同浓度的AgNO_(3)后制得改性复合膜。通过扫描电子显微镜(SEM)、X射线衍射(XRD)、X射线光电子能谱(XPS)、热重分析(TGA)、傅里叶红外光谱(FT-IR)对改性复合膜进行结构和形貌表征,结果表明:改性复合膜质地均匀,部分Ag^(+)以单质银的形式与膜中的成分相互作用,膜热稳定性良好,满足保鲜材料要求。改性复合膜对大肠杆菌(E.coli)及白色葡萄球菌(S.albus)的抑制情况进一步证明了其中存在单质Ag粒子,对S.albus的抑制能力更强。用改性复合膜包裹蓝莓,存储10 d后的失重率低于7%、颜色几乎没有变化;可溶性固形物损失小于3%、可滴定酸下降不明显,当加入1 mL 0.01 mol/LAgNO_(3)时,改性复合膜的保鲜性能相对较好。
