亚致死剂量的PH3熏蒸对嗜虫书虱种群生长发育的影响

研究了在室内几种不同亚致死剂量PH3熏蒸对嗜虫书虱Liposcelis entomophila(Enderlein)平均产卵量、卵孵化率和数量趋势指数的影响,确定了PH3对实验室嗜虫书虱的几种亚致死剂量LC5、LC10、LC20、LC30、LC40和LC50.用以上6种亚致死剂量PH3熏蒸对F0代嗜虫书虱的平均产卵量的抑制率分别达到56.72%、49.47%、39.16%、22.89%、15.70%及5.75%,但随着饲养代数的增加,对雌虫产卵抑制率逐渐降低.说明亚致死剂量PH3熏蒸嗜虫书虱随着熏蒸世代的增加而逐步减弱.亚致死剂量PH3熏蒸对雌虫产卵具有一定的刺激作用.对卵的孵化率的抑制效果差异不显著,几种亚致死剂量PH3熏蒸对F2代卵的孵化率差异不显著(P<0.05).在LC20以下亚致死剂量对3个世代种群数量趋势指数影响差异不显著,高于LC20以上的浓度对种群数量趋势指数影响差异显著(P<0.05).研究结果表明:亚致死剂量的PH3对嗜虫书虱具有一定的抑制作用,但长期使用不仅会导致抗性的产生,而且还有刺激其种群爆发的可能.     

磷化氢亚致死浓度对赤拟谷盗卵和蛹的影响

研究了实验室条件下磷化氢亚致死浓度中赤拟谷盗卵和蛹的发育与死亡情况 .通过低的亚致死磷化氢浓度处理赤拟谷盗的卵和蛹 ,发现此虫的卵在低浓度磷化氢 ( 5mL/m3、1 0mL/m3)中仍可发育和孵化 ,且发育时间延长 ,但在磷化氢中不孵化的卵其死亡速度小于正常条件下的卵 .在稍高浓度 ( 2 0mL/m3、40mL/m3以上 )时 ,卵不能孵化 ,但从外观上也不马上死亡 ,死亡速度明显慢于对照组 .在亚致死浓度下蛹对磷化氢的耐受力较卵要小 ,同样浓度时引起的蛹死亡率也较大 ,且死亡速度快     

磷化氢亚致死浓度对赤拟谷盗卵和蛹的影响

研究了实验条件下磷化氢亚致死浓度中赤拟谷盗卵和蛹的发育与死亡情况，通过低的亚致死磷化氢浓度处理赤拟谷盗的卵和蛹，发现此虫的卵在低浓度磷化氢（5ml/m^3,10mL/m^3)中仍可发育和孵化，且发育时间延长，但在磷化氢中不孵化的卵其死亡速度小于正常条件下的卵，在稍高浓度（20mL/m^3,40mL/m^3以上）时，卵不能孵化，但从外观上也不马上死亡，死亡速度明显慢于对照组，在亚致死浓度下蛹对磷化氢的耐受力较卵要小，同样浓度时引起的蛹死亡率也较大，且死亡速度快。     

虫灵灭中吡虫啉和巴沙的同时测定

以ClC-ODS(150mm×6.0mm,5μm)为色谱柱,V(甲醇)∶V(水)(φ=0.2%氨水溶液)=55∶45为流动相,其体积流量为0.8mL/min;用SPD-6AV紫外检测器检测波长为270nm,柱温为室温,灵敏度为0.16AUFS.实验表明,吡虫啉的线性方程为A=481586.1c-2381.26,r=0.9989,回收率为108%,RSD=2.56%;巴沙的线性方程为A=74333.36c-686.096,r=0.9975,回收率为106%,RSD=0.34%;吡虫啉的相对标准偏差RSD=0.187%,巴沙的相对标准偏差RSD=2.29%;并对流动相和检测波长进行了优化,确定了最佳的流动相和检测波长.     

氨氮对内循环生物流化床亚硝化过程影响

为实现内循环生物流化床(ITFB)短程脱氮处理高氨氮废水,在小试ITFB反应器内考察了氨氮浓度对生物膜亚硝化特性的影响.通过5个月的连续试验,研究了ITFB反应器历经启动培养、短暂亚硝化、硝化系统破坏、硝化系统恢复、完全硝化五个过程中,氨氮、硝酸盐氮和亚硝酸盐氮的转化规律及游离氨毒性作用对短程硝化过程的影响.试验结果表明:反应器启动初期出现了短暂亚硝化,平均亚硝化率为79%;在进水氨氮浓度增加到300 mg/L时,系统再次实现了亚硝化,平均亚硝化率达81%,但由于游离氨浓度的影响使得系统硝化能力受到严重影响,系统氨氮去除率降低至22%;系统恢复后,亚硝化现象不明显.反应器内游离氨浓度随进水氨氮浓度升高而增加至8 mg/L时,系统内硝化细菌和亚硝化细菌活性均受到抑制.通过提高进水氨氮浓度来实现系统短程脱氮过程稳定运行的可逆性较差.     

Antiplasticizing effect of MOCA on poly(vinyl chloride)

An obvious antiplasticizing effect has been observed in PVC with small amount of MOCA, 3,3’-dichloro-4,4’-diamino-diphenylmethane. PVC-MOCA interaction and crystallization behavior of PVC/MOCA blends were investigated in detail to explain the mechanism of antiplasticization on the basis of a series of techniques including DMA, FTIR, and DSC. The results of mechanical properties tests show that the tensile strength of PVC with 5 phr of MOCA reaches a maximum value, 69.5 Mpa, which is about 23 % higher than that of pure PVC. The rise in tensile strength was attributed to an antiplasticizing effect of MOCA on PVC as confirmed by DMA measurements. The evidences from FTIR reveal that a strong hydrogen-bonding interaction takes place between the nitrogen atom of –NH2 groups in MOCA and the methine proton of PVC repeat units. The results of DSC analysis indicate that crystallization behavior of MOCA is suppressed completely and the crystallinity of PVC decreases with the increase of MOCA amount.     

β-CD对离子型表面活性剂CMC影响的研究

在25℃时用电导法研究了系列阳离子型表面活性剂十烷基三甲基氯化铵(DTMAC)、十二烷基三甲基氯化铵(DTAC)、十四烷基三甲基氯化铵(TTAC)、十六烷基三甲基氯化铵(CTAC)、十八烷基三甲基氯化铵(OTAC)和阴离子型表面活性剂十二烷基硫酸钠(SDS)，及十二烷基苯磺酸钠(SDBS)作为客体，与主体分子β-环糊精(β-CD)生成包合物的情况．实验结果表明：当加入β-CD后，阳离子型表面活性剂(DTMAC、DTAC、TrAC、CTAC、OTAC)及阴离子型表面活性剂(SDS、SDBS)胶束水溶液体系的表观临界胶束浓度(CMC^*)随．β-CD物质的量浓度的增加呈线性增加关系．经最小二乘法拟合，在一定的物质的量浓度范围内CMC^*值符合线性增加关系的经验表达式．表面活性剂胶束水溶液体系临界胶束浓度的外推值(CMCExpt)和实验值(CMCExp)与其献值(CMCRef)相吻合．同时，详细论述了环糊精及环糊精与表面活性剂单体分子所生成的包合物与胶束形成过程的联系，以及环糊精与胶束的聚集状态之间的相互关系，它将对模拟酶催化具有重要的理论和实际应用意义．     

氧体积分数对乙烯扩散火焰中烟黑生成影响的实验

为了研究氧体积分数对扩散火焰中烟黑颗粒生长和聚合特性的影响,采用热泳沉积取样结合透射电子显微镜(TEM)图像,分析富氧和贫氧环境下乙烯/O2/N2扩散火焰中烟黑颗粒的粒径和颗粒凝聚体平均颗粒数,并采用激光消光法同步测量烟黑颗粒在火焰轴向和径向的体积分数分布.实验结果表明：对于乙烯扩散火焰,氧体积分数的增加,使火焰中心同一高度上的烟黑粒径和凝聚体平均颗粒数增大,进而引起烟黑体积分数增大,峰值位置前移;在火焰径向方向烟黑颗粒分布向中心收缩,边缘位置烟黑体积分数增大.对于本文讨论的扩散火焰,氧体积分数的增加对烟黑的生成具有促进作用,这对于火焰颗粒污染物的控制研究具有参考意义.     

北京市采暖期大气中PM_(10)和PM_(2.5)质量浓度变化分析

对北京市2003年11月至12月间供暖期中大气悬浮颗粒物污染状况作了较详细的监测.数据表明,北京市的这段时间,其PM10和PM2.5质量浓度因日因月而异,其中PM10平均质量浓度为253.1μg/m3,超过国家二级标准(1996)1.9倍,PM2.5的变化幅度在8.9-276.2μg/m3之间,其平均值为145.2μg/m3,超过1999-2000年监测数值38.4％;其污染源和影响因素之间关系的研究表明:在供暖期间,温度、湿度和风速对PM10和PM2.5的累积和消散也起着至关重要的作用.     

Inhibitory effect of Cr（Ⅵ） on activities of soil enzymes

To evaluate the influence of various Cr(VI) concentrations (0.05, 0.25, 0.50, 1.00 and 2.00 g/kg) on the activity of soil enzymes, the activities of catalase, polyphenol oxidase, dehydrogenase, alkaline phosphatase in soils were investigated in the incubation experiment with a period of 35 d. The results indicate that all the tested Cr(VI) concentrations significantly inhibit dehydrogenase activity by over 70% after 35 d. The activity of alkaline phosphatase is slightly inhibited during the whole experiment except for on the day 7. Cr(VI) has no obvious effect on the activity of catalase in soil. On the contrary, Cr(VI) stimulates the activity of polyphenol oxidase. The results suggest that dehydrogenase activity can be used as an indicator for assessing the severity of chromium pollution. Foundation item: Projects(2006AA06Z374, 2007AA021304) supported by the National High-Tech Research and Development Program of China; Project(2008SK2007) supported by the Key Program of Science and Technology of Hunan Province, China     

Promotion effect of KOH on preparation of dissolved Fe (VI)

In order to improve the yield and stability of ferrate in solution, dissolved Fe (VI) prepared with NaOH and KOH respectively was compared in this study. The results showed that KOH is more suitable than NaOH for the preparation of dissolved Fe(VI) at temperature over 50 ℃. It is found that the dissolved Fe(VI)prepared with KOH increases quickly at first, and then slowly with the increasing concentrations of OH- and ClO~- , while it increases rapidly at first and then decreases rapidly with the increasing dosage of Fe(NO_3)_3·9H_2O. These results are different from that prepared with NaOH. It can be explained that solid K_2 FeO_4 salts can be formed in KOH solution, and it will lower the Fe (VI) concentration, counteract the decomposition of Fe(VI), and improve the yield of Fe(VI). The maximum ferrate concentration is 0. 163 mol/L obtained by 100 g/L Fe(NO_3)_3· 9H_2O and 6. 16 moL/L KOH at 65℃. The stability of Fe(VI) is greatly improved due to the hypochlorite existed in the dissolved ferrate, and only 24% Fe(VI) has been decomposed after 16 d for 1 mmol/L Fe(VI) at 25 ℃.     

单用户 OS 环境具有实时多任务特征系统(RTMT)的简化设计与实现

基于实时性和多任务特性，分析了微机操作系统的构造原理，在单用户ＯＳ下，结合任务调度方法论述了能实现实时性和多任务的实用设计过程，给出了程序设计要点，其结论对应用中的同类问题有普遍意义。