SPRING RUNOFF AND DRAINAGE N AND P LOSSES FROM HOG-MANURED CORN1

ABSTRACT: A two-year study was conducted to assess the effect of hog manure on the losses of nitrogen and phosphorus in runoff and drainage from grain-corn (Zea mays L.) plots, and the importance of spring versus annual loads. Treatments consisted of mineral N-P-K fertilizer applied at rates of 152 kg N ha^-1, 35 kg P ha^-1, and 86 kg K ha^-1; and hog (Sus scrofa domestica L.) manure applied preplant or post-emergence (six-to-eight leaf stage), at 152 kg N ha^-1, 39 kg P ha^-1, and 112 kg K ha^-1. The plots were rototilled (7 cm depth) in spring to incorporate fertilizer and preplant hog manure, and fall chisel-plowed (15 cm depth) to incorporate chopped corn residues. They were arranged in a completely randomized plot design. Flow volumes and nutrient levels in runoff and drainage waters were monitored year round but occurred mainly during the snowmelt (March 25-April 9), and post.snowmelt (April 10-May 13) periods. Of the total amount of water lost during snowmelt, 90 percent was in runoff, while 92 percent occurred as drainage in the post-snowmelt period. Sixty-five percent of the total annual volume of water lost was lost during these two periods as runoff and drainage. Treatments did not affect the annual snowmelt or post-snowmelt N and P loads. Total annual loads averaged 8.0 kg TKN ha^-1, 1.8 kg NH₄-N ha^-1, 43 kg NO₃-N ha^-1, 0.4 kg TP ha^-1, and 0.15 kg PO₄-P ha^-1. Spring (snowmelt and ost-snowmelt) runoff and drainage loads averaged 2.9 kg TKN ha^-1, 1.2 kg NH₄-N ha^-1, 18 kg NO₃-N ha^-1, 0.25 kg TP ha^-1, and 0.04 kg PO₄-P ha^-1, which were 40 percent to 70 percent of the yearly nutrient loads. Therefore, the hog manure management systems examined were of no greater threat to the environment than mineral fertilizers. However, spring N and P losses do represent an important part of the annual nutrient loss budget, even with conservation practices.     

Physical properties and biodegradability of blends containing poly(ε-caprolactone) and tropical starches

In order to assess feasibility of tropical starches (sago and cassava starches) as biodegradable plastic materials, blending with poly(-caprolactone) (PCL), a biodegradable polymer, was carried out. It was confirmed that the physical properties (tensile strength and elongation) of PCL/sago and PCL/cassava blends were similar to those of PCL/corn blend, suggesting that sago and cassava starches can also be blended with PCL for production of biodegradable plastic. However, the properties of all PCL/starch blends were still low compared with those of polyethylene. Enzymatic degradability evaluation showed that lipase degradation of PCL and-amylase degradation of starch increased as the starch content in the blend increased. Burial test of the blends for 1, 3, and 5 months was carried out and the rate of degradation of the PCL/sago blend was confirmed to be slower than those of PCL/corn and PCL/cassava blends. Observation of the film blends structure by scanning electron microscope revealed that the starch was dispersed in a PCL continuous phase. Furthermore, changes in the film surface before and after enyzme treatments were observed.     

含滑石粉的环保型聚乙烯包装材料的可环境消纳性能研究

借助人工加速老化、自然土壤填埋等实验方法 ,采用力学性能测试、扫描电镜 (SEM)、热重 -红外联用仪 (TG IR)等测试方法 ,对所研制的含滑石粉的环保型聚乙烯 (PE)塑料包装材料的可环境消纳性能进行探讨。实验结果表明 ,以PE为主材料 ,添加不易分解的滑石粉、生物活性剂、FeSt3 MnSt2 复合光敏剂 ,研制出的高填充可降解的PE塑料薄膜 ,具有良好的光 -生物降解性能 ,且可适用于焚烧处理。     

金属微孔材料及其在高温煤气除尘中的应用研究

介绍了一种新型的高性能金属微孔过滤材料———烧结金属丝网过滤材料及其特性。将该过滤材料应用于高温煤气的除尘过程中 ,试验表明 ,处理效果良好。对于煤气含尘浓度在 3 70 0— 490 0mg Nm3的煤气 ,经处理后 ,可降至 2 0mg Nm3以下 ,过滤效率 >99.5 %。     

玉米淀粉生产废水处理工程设计与实践

通过奋达淀粉有限公司生产废水的处理工程实践，介绍厌氧-二次氧化工艺处理高浓度玉米淀粉生产废水的调试运行情况，运行结果表明：在进水CODCr为3800mg／L、SS在200mg／L、pH为4～5。处理后水质CODCr〈100、SS〈70、pH为6-9，达到《污水综合排放标准》（GB8978-1996）一级标准。     

新型生物质粉体燃料破碎系统

生物质的破碎是生物质能源利用转化的前提条件。本文介绍了一种用于生物质精细破碎的成套系统，简述了其中粗破碎机、精破碎机的结构特点和工作原理，并对生物质破碎的原料和破碎产物以及系统的生产效率和生产成本进行了分析。     

酚醛树脂生产废水处理工艺

对于COD高达246000mg／L、挥发酚达11000mg／L的酚醛树脂生产废水的处理试验研究表明，采用树脂提取--二次缩合--催化氧化--SBR生化工艺是可行的。100℃下通过9h的延时缩合，可回收树脂25kg／m^3，COD和挥发酚去除率分别为。75％和66％；95--100℃下投药二次缩合4h，COD和挥发酚去除率分别达81％和99％；常温常压下投加二氧化氯1．2kg／m^3，催化氧化4h，COD和挥发酚去除率分别为41％和78％；脱氯混凝后，废水按1：4稀释(降低Cl^-浓度)，控制COD在600mg／L以下，经PAC--SBR生化工艺处理可达标排放。工程实践证明，废水处理效果达到预期目标，其经济技术指标具有先进性。     

稻草末固定白腐菌处理染料废水的研究

对采用微电解－白腐菌生物降解－石炭絮凝系统处理活性染料废水进行了研究。试验结果表明，废水的COD去除率和色度除率均达到95％以上，出水水质符合废水排放标准。     

Biodegradation of Coproducts from Industrially Processed Corn in a Compost Environment

Information pertaining to biodegradability of renewable polymeric material is critical for the design and development of single-use biodegradable consumer products. The rate and extent of biodegradation of corn fiber, corn zein, cornstarch, distillers grain, and corn gluten meal were evaluated in compost environments under variable temperature, pH, and moisture conditions. Generally, composts with higher temperature (40°C), neutral pH (7.0), and 50%–60% moisture appeared to be ideal for corn coproduct biodegradation, particularly for corn gluten meal and corn zein. Low moisture conditions slowed biodegradation considerably, but degradation rates improved when moisture content increased up to 60%. Thereafter, increased moisture particularly slowed the degradation of corn gluten meal and corn zein, whereas cornstarch degradation remained unaffected. At low pH (4.0) and high pH (11.0) the rate of degradation of most coproducts was slowed somewhat. Cornstarch degradation was slower at pH 7.0, but degradation improved with increased temperatures. Increase in compost temperature from 25 to 40°C (in 5°C increments) also improved biodegradation of corn fiber and distillers grain. Addition of 1% urea to compost as a nitrogen source decreased the extent of biodegradation nearly 40% for corn gluten meal and corn zein, and 20% for cornstarch samples. Treatment of compost with 0.02% azide inhibited biodegradation of all coproducts, suggesting that the presence of metabolically active microbial cells is required for effective degradation of biobased materials in a compost environment.     

钢板酸洗液回收Fe2O3粉制取高档永磁铁氧体预烧料的研究

以钢板酸洗废酸液回收的Fe2O3粉为主要原料,制备了永磁铁氧体预烧料及器件。研究了工艺制度如预烧温度、保温时间、摩尔比对预烧料磁学性能的影响等。制取的永磁铁氧体材料的磁性能达到Br=420mT,Hcb=215KA/m,(BH)max=32.4KJ/m3。