氨氮浓度对鸡粪中高温甲烷发酵的影响

为探究氨氮浓度对鸡粪中高温甲烷发酵的影响，采用固定水力停留时间（HRT，20d），提高进料总固体浓度（TS，5%、7.5%和10%）的方式增加氨氮浓度，通过265d的长期甲烷发酵试验，比较了不同氨氮浓度条件下鸡粪中高温甲烷发酵效果和污泥的比产甲烷活性.结果显示，TS由5%增至10%，中高温反应器中氨氮浓度由2.1~2.5g/L增至6.1~6.5g/L，对应的比产甲烷活性分别降低了44%和100%，中温反应器中挥发性脂肪酸由0.4g/L增至7.6g/L，甲烷产率由253mL/gTS降至203mL/gTS；高温反应器中挥发性脂肪酸由0.4g/L增至26.1g/L，甲烷产率由181mL/gTS降至18mL/gTS.氨氮浓度对高温甲烷发酵系统的抑制作用更加明显.     

鸡粪堆肥水溶性有机物转化特性研究

采用离子色谱和三维荧光光谱,分别对鸡粪堆肥不同阶段水溶性有机物(DOM)中典型小分子有机酸、磷酸和荧光有机物进行了研究。分析显示,所研究的7种酸(乙酸、琥珀酸、苹果酸、草酸、柠檬酸、酒石酸及磷酸)中,苹果酸的含量最高(1 000 mg/L),草酸的浓度最低(3 mg/L),琥珀酸和柠檬酸未检测到。随着堆肥的进行,各种酸的含量先上升而后下降,堆肥结束降至最低;堆肥过程样品所有荧光峰强度之和与COD达到显著相关(R=0.917,P0.05),类蛋白荧光峰强度与总荧光峰强度的比值不断降低,而类富里酸荧光峰强度与总荧光峰强度的比值不断上升。结果表明,堆肥过程小分子有机酸主要出现在堆肥中期;类蛋白荧光强度或类富里酸荧光强度与总荧光强度之比可以有效表征堆肥腐熟过程。     

Production of the broad specific monoclonal antibody against sarafloxacin for rapid immunoscreening of 12 fluoroquinolones in meat

The objective of this study was to produce a generic antibody for immunoassay of fluoroquinolone drugs in meat. Two novel haptens of sarafloxacin were synthesized that were used to produce the monoclonal antibodies. The obtained monoclonal antibodies simultaneously recognized 12 fluoroquinolone drugs (sarafloxacin, diflocaxin, marbofloxacin, ofloxacin, ciprofloxacin, enrofloxacin, norfloxacin, pefloxacin, lomefloxacin, amifloxacin, enofloxacin and danofloxacin). After evaluation of different coating antigen/antibody combinations, a heterologous competitive indirect enzyme linked immunosorbent assay (ELISA) was developed to determine the 12 drugs. The crossreactivities to these analytes were in the range of 18%–113% and the limits of detection were in the range of 0.8–6.5 ng/mL depending on the compound. Eight fluoroquinolones licensed as veterinary drugs in China were fortified into blank chicken for ELISA analysis. The recoveries were in the range of 67.6%–94.6% with coefficients of variation lower than 12.4%. Therefore, this method could be used as a screen tool for routine monitoring of the residues of these fluoroquinolone drugs in animal derived foods.     

2-Undecanone and 2-tridecanone in field-grown onion

A field study was conducted to investigate the impact of soil amendments on concentrations of two volatile organic compounds, 2-undecanone and 2-tridecanone, in onion bulbs. The soil in five plots was mixed with sewage sludge, five plots were mixed with yard waste compost, five plots were mixed with laying hen manure each at 15 t acre^?1, and five unamended plots that never received soil amendments were used for comparison purposes. Plots (n = 20) were planted with onion, Allium cepa L. var. Super Star-F1 bulbs. Gas chromatographic/mass spetrometric (GC/MS) analyses of mature onion bulbs crude extracts revealed the presence of two major fragment ions that correspond to 2-undecanone and 2-tridecanone. Soil amended with yard waste compost enhanced 2-undecanone and 2-tridecanone production by 31 and 59%, respectively. Soil amended with chicken manure enhanced 2-undecanone and 2-tridecanone production by 28 and 43%, respectively. Concentrations of 2-undecanone and 2-tridecanone were lowest in onion bulbs of plants grown in sewage sludge and unamended soil, respectively. The increased concentrations of 2-undecanone and 2-tridecanone in onion bulbs may provide a protective character against insect and spider mite attack in field grown onions.     

玉米秸与鸡粪混合厌氧消化产气性能与协同作用

研究了玉米秸与鸡粪在不同混合比例条件下的厌氧消化产气性能和协同作用效果。设计了9种玉米秸与鸡粪的混合比例(1∶0、1∶1、1∶2、1∶3、1∶4、2∶1、3∶1、4∶1、0∶1),每种比例分别在3个不同负荷(50、65和80 g/L)下进行混合厌氧消化。结果表明,与未预处理玉米秸与鸡粪混合厌氧消化相比,NaOH预处理玉米秸与鸡粪混合厌氧消化的单位TS产气量提高了5.5%～62%。当预处理玉米秸与鸡粪的混合比例为1∶2、上料负荷为50 g/L时消化产气性能最好,此时的累积甲烷产量达到19 488 mL,比相同负荷下单一玉米秸厌氧消化的累积甲烷产量高出32.6%,比单一鸡粪厌氧消化的累积甲烷产量高出11.4%。混合厌氧消化协同作用的贡献率达到7.1%～17.7%,其中玉米秸与鸡粪的比例为1∶2时,其贡献率与其他比例相比高出25%～150%。可以为粪草混合原料厌氧消化提供设计和运行依据。     

我国热带地区胶-茶-鸡农林复合系统物质循环研究

以海南省文昌市典型的胶-茶-鸡农林复合模式为研究对象 ,以单作胶园、胶茶间作园为对照 ,采用定量研究与定性分析相结合的方法 ,研究其物质循环规律。结果表明 ,胶-茶-鸡农林复合系统的氮、磷输入、输出量最大 ,系统外物质投入率比另两系统明显减少 ,系统内养分循环量增加 ,因此 ,该系统具有较合理的物质循环结构。     

The Potential Use of Chicken-Drop Micro-Organisms for Oil Spill Remediation

An examination of chicken-drop micro-organisms for oil spill remediation is presented in this work. The chicken droppings contained aerobic heterotrophs (1.2×10⁸ CFU g^–1), total fungi (3.4×10⁴ CFU g^–1) and crude oil (transniger pipeline crude, TNP) degrading bacteria (1.5×10⁶ CFU g^–1). The crude oil degraders were identified as species of Micrococcus, Bacillus, Pseudomonas, Enterobacter, Proteus, Klebsiella, Aspergillus, Rhizopus, and Penicillium. Pseudomonas aeruginosa CDB-06 and species of Bacillus CDB-08 and Penicillium CDF-10 degraded the crude oil at exceedingly high rates. Pseuedomonas aeruginosa CDB-06 degraded 65.5 percent of the crude oil after 16 days, while Bacillus sp. CDB-08, and Penicillium sp. CDF-10 degraded 65.3 percent, and 53.3 percent, respectively of the crude oil over the same period. The chicken droppings also had a pH 7.3, 18.5 percent moisture content, 2.3 percent total nitrogen, and 0.5 percent available phosphorus. Addition of oil polluted soil (10 percent (v/w) pollution level) with chicken droppings enhanced degradation of the crude oil in the soil. 68.2 percent of the crude oil was degraded in the soil amended with chicken droppings, whereas only 50.7 percent of the crude oil was degraded in the unamended soil after 16 days. The amendment raised the acidic reaction (pH 5.7) of the oil-polluted soil to alkaline (pH 7.2) within 16 days. Chicken droppings could, therefore, be used in an integrated oil pollution abatement program.     

鸡粪/木屑强制通风堆肥的研究

在鸡粪与木屑的体积配比为3:2的情况下,采用强制通风堆肥工艺考察了堆肥产品的物理化学特征和生物学特征的变化。研究结果表明,堆肥的第2天就达到高温阶段(≥55℃)并能保持5d以上,局部温度达71℃,大肠杆菌由最初时的2.8×1010CFU/g降到试验结束时的1.8×102CFU/g。堆体温度的变化引起了细菌、真菌和放线菌数量发生变化。堆肥过程中有机质、C/N比、含水率、NH4+-N明显下降,而NO3——N的含量成上升趋势。pH在第1周内升高8.45,随后逐渐降低到7.22。在第43天堆肥产品的水芹种子发芽指数达到了92.2%,堆肥产品已经达到腐熟。     

兽药金霉素在畜禽粪便上的吸附特征研究

通过振荡平衡吸附试验,研究了兽药金霉素在鸡粪和猪粪上的吸持特征并对其吸附机制和影响因素进行探讨.结果表明,金霉素能被畜禽粪便强烈吸附,吸附过程属于快速吸附,吸附等温线呈非线性,能用Freundlich模型很好地描述;雨水很难解吸被粪便吸附的金霉素,存在解吸迟滞现象,用甲醇、3 mol/L NaCl和3 mol/L MgCl2 3种溶液仅分别解吸出了18.3%～20.4%、18.7%～19.4%和55.7%～57.6%被粪便吸附的金霉素.金霉素在畜禽粪便上的吸附受pH和离子强度影响,随pH值和离子强度增大吸附量减少,二价钙离子体系比一价钠离子体系对吸附的影响大.表明有机质吸附和阳离子交换可能是金霉素在畜禽粪便上主要的吸附机制.     

Carbon dioxide emission in relation with irrigation and organic amendments from a sweet corn field

Soil moisture and organic matter level affects soil respiration and microbial activities, which in turn impact greenhouse gas (GHG) emissions. This study was conducted to evaluate the effect of irrigation levels (75% [deficit], 100% [full], and 125% [excess] of reference crop evapotranspiration requirements), and organic amendments (OA) type (chicken manure [CM] and bone meal [BM]) and OA application rates (0,168, 336 and 672 kg total N ha^?1) on (i) soil physical properties (bulk density, organic matter content and soil moisture content) and (ii) soil carbon dioxide (CO₂) emissions from a highly weathered tropical Hawai'ian soil. Carbon dioxide readings were consistently taken once or twice a week for the duration of the cropping season. A drip irrigation system was used to apply the appropriate amount of irrigation water to the treatment plots. Treatments were randomly selected and corresponding organic amendments were manually incorporated into the soil. Plots were cultivated with sweet corn (Zea mays ‘SS-16’). Soil moisture content within and below the rootzone was monitored using a TDR 300 soil moisture sensor (Spectrum Technologies, Inc., Plainfield, IL, USA) connected with 12 cm long prongs. Soil bulk density and organic matter content were determined at the end of the cropping season. Analysis of variance results revealed that OA type, rate, and their interaction had significant effect on soil CO₂ flux (P < 0.05). Among the OA rates, all CM mostly resulted in significantly higher soil CO₂ fluxes compared to BM and control treatment (p < 0.05). The two highest rates of BM treatment were not significantly different from the control with regard to soil CO₂ flux. In addition, organic amendments affected soil moisture dynamics during the crop growing season and organic matter content measured after the crop harvest. While additional studies are needed to further investigate the effect of irrigation levels on soil CO₂ flux, it is recommended that in order to minimize soil CO₂ emissions, BM soil amendments could be a potential option to reduce soil CO₂ fluxes from agricultural fields similar to the one used in this study.