生物填料的投加对厌氧序批式反应器启动影响研究

采用厌氧序批式反应器(ASBR)和厌氧序批式生物膜反应器(ASBBR),以相同的反硝化污泥作为接种污泥,自配模拟废水,调节进水pH为7.5~8.0,反应器中水体温度为(30±0.5)℃,研究了生物填料的投加对厌氧序批式反应器厌氧氨氧化反应的启动影响。经过120 d运行,ASBBR成功启动了厌氧氨氧化反应,NH3-N容积负荷为96mg/(L·d),NH3-N去除率达到81.53%,NH3-N、NO2--N减少量与NO3--N生成量之比为1:1.11:0.25。而未投加填料的ASBR没有发生厌氧氨氧化反应,NH3-N容积负荷为22 mg/(L·d),NH3-N去除率达到23.36%,NH3-N、NO2--N减少量与NO3--N生成量之比为1:0.91:1.18。实验结果表明,生物填料的投加使ASBBR易于形成厌氧环境,有利于厌氧氨氧化反应器的启动,同时有利于NH3-N的去除。     

盐度条件下UASB厌氧氨氧化反应器启动与运行研究

考察了低盐度条件下启动厌氧氨氧化反应器及其处理高氮高盐废水的可行性。结果表明,在NaCl为3.0 g/L的低盐度、氮负荷为130 mg/(L·d)的条件下采用普通活性污泥作为接种污泥,可在165 d内成功启动UASB厌氧氨氧化反应器,对TN、NH4+-N、NO2--N的平均去除率分别达到80.0%、98.8%、90.0%,NH4+-N、NO2--N去除量与NO3--N生成量之比为1∶(1.15±0.08)∶(0.20±0.02),出水pH稳定在8.42左右,污泥呈棕褐色颗粒状,存在部分浅红色颗粒污泥。将总氮容积负荷和盐度(NaCl)逐步提高到258 mg/(L·d)和12.0 g/L,反应器脱氮效率保持高效、稳定。在低盐度条件下启动厌氧氨氧化反应器之后,通过适当的氮负荷和盐度提升方式,可以处理高氮高盐废水。     

UAF反应器启动厌氧氨氧化反应的试验研究

本试验以普通活性污泥为种泥,采用升流式厌氧生物滤床(UAF)反应器,在pH为7.5的室温条件下,以NH4Cl和NaNO2配制人工模拟废水,通过逐步提高NH4+-N与NO2--N的负荷对厌氧氨氧化菌进行培养与驯化,在反应器运行到148 d左右时NH4+-N与NO2--N去除率分别达到56%、62%,且在之后的运行过程中其去除率呈同步变化,NH4+-N与NO2--N同时去除。通过镜检发现在反应器下部形成了具有厌氧氨氧化活性的棕红色颗粒污泥,实现了厌氧氨氧化反应的快速启动。     

厌氧氨氧化一反硝化耦合处理合成革废水研究

采用厌氧氨氧化(Anammox)-反硝化偶合反应器处理合成革废水,在人工配水、常温、控制pH在7.5~8.0。结果表明,经过79 d的培养,历经启动初期、活性提高期、负荷提高期等3个启动阶段,系统的TN去除率达70%,成功实现厌氧氨氧化耦合反硝化的启动,系统中厌氧氨氧化和反硝化均发挥一定的TN去除作用,以厌氧氨氧化作用为主。继续运行30 d,反应器状况保持良好,在进水NO2--N与NH4+-N质量浓度的比在1.2~1.5,且COD为60~70 mg/L的条件下,TN去除率可稳定在80%以上,TN容积去除速率约0.29~0.41 kg/(m3·d)。出水水质稳定,处理效果较好。     

ANAMMOX反应器快速启动及对反硝化聚磷的影响研究

硝化菌的生长快于厌氧氨氧化菌,通过培育硝化生物膜,利用硝化菌的基质多样性和代谢多样性,可使生物膜由催化硝化反应过渡到催化厌氧氨氧化反应,加速ANAMMOX反应器的启动。经过2个月的运行,成功地启动了ANAMMOX反应器,而且反应器运行性能稳定。将厌氧氨氧化引入反硝化聚磷系统中,试验结果表明,在COD和TP的去除率保持基本不变的情况下,NH4+-N的去除率从23%上升到87%,TN的去除率从88%提高到93%,出水NH4+-N和NO2--N的质量浓度均低于2mg/L。     

厌氧氨氧化反应的影响因素研究

以厌氧氨氧化活性污泥作为接种物,以无机盐培养液作为实验用水,考察了溶解氧、进水NO2--N与NH4＋-N的比值对厌氧氨氧化反应的影响。反应体系中硝酸盐的产生量随溶解氧浓度增加而增大,总氮去除率则随溶解氧浓度的增加而降低,除氧实验时出水NO3--N浓度平均为67.2mg/L,总氮去除率平均为73.9%;不除氧时出水NO3--N浓度平均为83.0mg/L,总氮去除率平均为67.8%;当进水NO2--N与NH4＋-N比值为1.16时,利于厌氧氨氧化反应的进行,总氮去除率为62.78%。     

常温条件下接种OLAND污泥启动Anammox反应器的研究

采用固定床生物膜反应器(FBR)常温条件下接种OLAND污泥启动厌氧氨氧化(Anammox)反应器。温度15~25℃,水力停留时间(HRT)从2.0 d缩短至1.5 d,进水NH+4-N和NO-2-N的质量浓度分别从60 mg/L和30 mg/L逐步增加到320mg/L和260 mg/L。启动第1天,NH+4-N和NO-2-N即实现同步去除,首次表现出Anammox活性。反应器历经101 d,Anammox工艺成功启动。在启动过程的稳定期(第103~111天),进水NH+4-N和NO-2-N达到320 mg/L和260 mg/L,NH+4-N和NO-2-N的平均去除率均大于90%,其平均去除速率分别为167.61 g/(m3·d)和198.78 g/(m3·d);总氮负荷达387 g/(m3·d),总氮平均去除率为84.61%,总氮去除速率(NRR)高达336.44 g/(m3·d)。反应器效果良好,Anammox工艺稳定运行。     

厌氧氨氧化SBBR启动过程中菌群演替分析

采用序批式生物膜反应器(SBBR),以混合污泥作为接种污泥,研究了反应器启动过程中菌群演替规律。结果表明,通过逐步提高进水NH4+-N和NO2--N含量的方式将SBBR的N容积负荷由0.10 g/(L·d)提升至1.164 g/(L·d),经过144 d成功启动厌氧氨氧化SBBR,TN去除率达93.92%,厌氧氨氧化活性为5.86 mg/(g·h)。在反应器启动过程中,厌氧氨氧化菌的丰度不断升高,其它非功能菌的丰度逐渐降低。稳定运行期,浮霉菌门在活性污泥和生物膜上的丰度有显著的差异,前者为8.83%,后者为24.21%。3种检出的厌氧氨氧化菌属在活性污泥和生物膜上的差异也十分明显,Candidatus Jettenia、Candidatus Brocadia和Candidatus Kuenenia在活性污泥中的丰度分别为2.89%、2.29%和0.65%,而在生物膜的丰度分别为10.04%、5.93%、2.22%。     

部分亚硝化-厌氧氨氧化联合工艺处理含氮废水的研究

部分亚硝化-厌氧氨氧化联合工艺是一种新型的废水脱氮工艺。实验采用模拟废水,进水氨氮浓度为600 mg/L。亚硝化SBR反应器在温度为30℃、HRT为24 h、DO≈0.2 mg/L的运行条件下,将废水中的一部分氨氮氧化成亚硝氮,并使得亚硝化SBR反应器出水中NH4+-N和NO2--N比值接近1∶1.32后,再作为厌氧氨氧化SBR反应器进水;厌氧氨氧化SBR反应器在温度为37℃、HTR为24 h的运行条件下,将氨氮和亚硝氮转化为N2。实验结果表明,部分亚硝化-厌氧氨氧化联合工艺脱氮效果较好,废水中氮的去除率可达94.44%。     

Anammox反应器快速启动的操作策略

通过接种普通活性污泥并添加生物载体,39天成功启动厌氧氨氧化反应器。稳定期间,NH+4-N和NO-2-N的平均转化率分别达到96.6%、98.5%,TIN平均去除率为84.4%,TIN最高去除率达到了88.5%。氨氮和亚硝态氮浓度提升至180 mg/L左右,反应器出现亚硝态氮和硝态氮的积累以及出水p H明显小于进水p H的状况,为了解除亚硝酸盐的抑制,将基质浓度降低到60 mg/L,采用瞬时进水的方式后反应器运行良好。     

Insect antifeedant properties of anthranoids from the genusVismia

Vismiones and ferruginins, representatives of a new class of lypophilic anthranoids from the genusVismia were found to inhibit feeding in larvae of species ofSpodoptera, Heliothis, and inLocusta migratoria.     

Direct observation of freeze-thaw instability of latex coatings via high pressure freezing and cryogenic SEM

Despite its industrial importance, the subject of freeze-thaw (F/T) stability of latex coatings has not been studied extensively. There is also a lack of fundamental understanding about the process and the mechanisms through which a coating becomes destabilized. High pressure (2100 bar) freezing fixes the state of water-suspended particles of polymer binder and inorganic pigments without the growth of ice crystals during freezing that produce artifacts in direct imaging scanning electron microscopy (SEM) of fracture surfaces of frozen coatings. We show that by incorporating copolymerizable functional monomers, it is possible to achieve F/T stability in polymer latexes and in low-VOC paints, as judged by the microstructures revealed by the cryogenic SEM technique. Particle coalescence as well as pigment segregation in F/T unstable systems are visualized. In order to achieve F/T stability in paints, latex particles must not flocculate and should provide protection to inorganic pigment and extender particles. Because of the unique capabilities of the cryogenic SEM, we are able to separate the effects of freezing and thawing, and study the influence of the rate of freezing and thawing on F/T stability. Destabilization can be caused by either freezing or thawing. A slow freezing process is more detrimental to F/T stability than a fast freezing process; the latter actually preserves suspension stability during freezing. Presented at the 82nd Annual Meeting of the Federation of Societies for Coatings Technology, October 27–29, 2004 in Chicago, IL. Tied for first place in The John A. Gordon Best Paper Competition.     

Ethanol and (−)-α-Pinene: Attractant Kairomones for Bark and Ambrosia Beetles in the Southeastern US

In 2002–2004, we examined the flight responses of 49 species of native and exotic bark and ambrosia beetles (Coleoptera: Scolytidae and Platypodidae) to traps baited with ethanol and/or (−)-α-pinene in the southeastern US. Eight field trials were conducted in mature pine stands in Alabama, Florida, Georgia, North Carolina, and South Carolina. Funnel traps baited with ethanol lures (release rate, about 0.6 g/day at 25–28°C) were attractive to ten species of ambrosia beetles (Ambrosiodmus tachygraphus, Anisandrus sayi, Dryoxylon onoharaensum, Monarthrum mali, Xyleborinus saxesenii, Xyleborus affinis, Xyleborus ferrugineus, Xylosandrus compactus, Xylosandrus crassiusculus, and Xylosandrus germanus) and two species of bark beetles (Cryptocarenus heveae and Hypothenemus sp.). Traps baited with (−)-α-pinene lures (release rate, 2–6 g/day at 25–28°C) were attractive to five bark beetle species (Dendroctonus terebrans, Hylastes porculus, Hylastes salebrosus, Hylastes tenuis, and Ips grandicollis) and one platypodid ambrosia beetle species (Myoplatypus flavicornis). Ethanol enhanced responses of some species (Xyleborus pubescens, H. porculus, H. salebrosus, H. tenuis, and Pityophthorus cariniceps) to traps baited with (−)-α-pinene in some locations. (−)-α-Pinene interrupted the response of some ambrosia beetle species to traps baited with ethanol, but only the response of D. onoharaensum was interrupted consistently at most locations. Of 23 species of ambrosia beetles captured in our field trials, nine were exotic and accounted for 70–97% of total catches of ambrosia beetles. Our results provide support for the continued use of separate traps baited with ethanol alone and ethanol with (−)-α-pinene to detect and monitor common bark and ambrosia beetles from the southeastern region of the US.     

Methyl 2,4,6-decatrienoates Attract Stink Bugs and Tachinid Parasitoids

Halyomorpha halys (Stål) (Pentatomidae), called the brown marmorated stink bug (BMSB), is a newly invasive species in the eastern USA that is rapidly spreading from the original point of establishment in Allentown, PA. In its native range, the BMSB is reportedly attracted to methyl (E,E,Z)-2,4,6-decatrienoate, the male-produced pheromone of another pentatomid common in eastern Asia, Plautia stali Scott. In North America, Thyanta spp. are the only pentatomids known to produce methyl 2,4,6-decatrienoate [the (E,Z,Z)-isomer] as part of their pheromones. Methyl 2,4,6-decatrienoates were field-tested in Maryland to monitor the spread of the BMSB and to explore the possibility that Thyanta spp. are an alternate host for parasitic tachinid flies that use stink bug pheromones as host-finding kairomones. Here we report the first captures of adult and nymph BMSBs in traps baited with methyl (E,E,Z)-2,4,6-decatrienoate in central Maryland and present data verifying that the tachinid, Euclytia flava (Townsend), exploits methyl (E,Z,Z)-2,4,6-decatrienoate as a kairomone. We also report the unexpected finding that various isomers of methyl 2,4,6-decatrienoate attract Acrosternum hilare (Say), although this bug apparently does not produce methyl decatrienoates. Other stink bugs and tachinids native to North America were also attracted to methyl 2,4,6-decatrienoates. These data indicate there are Heteroptera in North America in addition to Thyanta spp. that probably use methyl 2,4,6-decatrienoates as pheromones. The evidence that some pentatomids exploit the pheromones of other true bugs as kairomones to find food or to congregate as a passive defense against tachinid parasitism is discussed.     

2007～2008年世界塑料工业进展

收集了2007年7月～2008年6月世界塑料工业的相关资料,介绍了2007～2008年国外塑料工业的发展情况,提供了世界塑料产量、消费量及全球各类树脂的需求量及产能情况.按通用热塑性树脂(聚乙烯、聚丙烯、聚苯乙烯、聚氯乙烯、ABS树脂)、工程塑料(尼龙、聚碳酸酯、聚甲醛、热塑性聚酯、聚苯醚)、特种工程塑料(聚苯·硫醚、液晶聚合物、聚醚醚酮)、通用热固性树脂(酚醛、聚氨酯、不饱和聚酯树脂、环氧树脂)不同品种的顺序,对树脂的产量、消费量、供需状况及合成工艺、产品应用开发、树脂品种的延伸及应用的进一步扩展等技术作了详细介绍.     

2005～2006年国外塑料工业进展

收集了2005年7月～2006年6月国外塑料工业的相关资料,介绍了2005—2006年国外塑料工业的发展情况。提供了世界塑料产量、消费量及全球各类树脂生产量以及各国塑料制品的进出口情况。作为对比,介绍了中国塑料的生产情况。按通用热塑性树脂（聚乙烯、聚丙烯、聚苯乙烯、聚氯乙烯、ABS树脂）、工程塑料（聚酰胺、聚碳酸酯、聚甲醛、热塑性聚酯、聚苯醚）、通用热固性树脂（酚醛、聚氨酯、不饱和树脂、环氧树脂）、特种工程塑料（聚苯硫醚、液晶聚合物、聚醚醚酮）的品种顺序,对树脂的产量、消费量、供需状况及合成工艺、产品开发、树脂品种的延伸及应用的扩展作了详细的介绍。