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1.
《广州化工》2021,49(6)
以膨润土为原料,制备锆功能化膨润土,并研究了其动态除磷性能。结果表明,一定程度增加初始磷浓度有助于提高磷吸附量,低流量和低pH环境下有利于磷的吸附,共存离子Cl~-和NO~-_3对磷吸附影响较小,但HCO~-_3抑制磷的吸附。增加NaOH浓度,有利于磷酸根的洗脱,以0.5 mol·L~(-1) NaOH为再生试剂,磷的洗脱率较高,达到92.0%。吸附剂具备较好的再生能力,经5次循环吸附和再生后,对磷的吸附量下降了12.5%。  相似文献   

2.
研究了玻璃基体上化学沉积Ni-P合金的工艺条件,讨论了碱性化学镀镍过程中硫酸镍、次磷酸钠和柠檬酸钠的质量浓度,温度以及pH对镀层沉积速率的影响,获得较佳工艺条件如下:硫酸镍30 g/L,次磷酸钠25 g/L,柠檬酸钠10g/L,温度45 ℃,pH=9.在此条件下获得的镍-磷合金镀层含磷3.2%,属于低磷镀层.采用氯化钯滴定法测得镀液的稳定时间达到30min.  相似文献   

3.
《应用化工》2022,(4):859-862
为了阐明改性钢渣陶粒应用于水体除磷的可行性,通过吸附实验研究了镧铁复合氧化物改性钢渣陶粒对低浓度磷的吸附特性,考察了投加量、pH、共存离子等因素对除磷率的影响,并研究其吸附动力学特性。采用NaOH作为再生剂,比较了吸附饱和的改性钢渣陶粒经不同条件再生处理后的除磷效果。结果表明,对于初始磷浓度1 mg/L的溶液,吸附剂投加量5 g/L,pH为7时,除磷率高达99.07%;HCO_3-和SO_4-和SO_4(2-)对除磷的抑制作用较强。吸附动力学过程符合准二级动力学模型。使用1.5 mol/L NaOH浸泡60 min是较为合理的再生条件,一次再生后的除磷率仍可达98.51%。  相似文献   

4.
采用电沉积法实现镧的固定,利用固定后的氧化镧去除污水中低浓度的磷酸盐,研究了不同电流、电沉积时间、温度、pH和电解液浓度条件下的除磷效果。通过显微镜观察除磷后的电极表面,以分光光度法测量除磷率,最佳除磷效果为97.2%。  相似文献   

5.
以沉积速率、镀层中磷的质量分数、孔隙率和硬度为评价指标,研究了乳酸、丙酸单独作配位剂及两者复配时镀层及镀液的性能。基础镀液配方及工艺条件为:NiSO_4·6H_2O 28g/L,NaH_2PO_2·H_2O 23g/L,CH_3COONa·3H_2O 20g/L,十二烷基硫酸钠8mg/L,硫脲2mg/L,pH值5.0±0.2,温度(80±2)℃,时间1h。结果表明:单独使用乳酸或丙酸作配位剂时,无法获得性能良好的化学镀低磷镍-磷合金镀层;只有将两者复配使用,才能获得理想的化学镀低磷镍-磷合金镀层。最佳的复配方案为乳酸18mL/L+丙酸10mL/L。此时,镀层中磷的质量分数为3.81%,沉积速率为16.31μm/h,孔隙率为0.70个/cm2,硬度为2 946MPa。  相似文献   

6.
几种微生物溶解磷矿粉的动态研究   总被引:6,自引:1,他引:5  
研究了尘埃芽孢杆菌、荧光假单孢菌和青霉对磷矿粉中磷的溶解能力.结果表明,该三种菌株均显著促进了磷矿粉的溶解,磷的浸出率最高可达6.7%.其中青霉的溶磷能力要强于尘埃芽孢杆菌和荧光假单孢菌。磷矿粉用量越低,磷的浸出率越高。随着培养时间增加,磷的浸出率逐渐升高.pH逐渐下降.但培养15d后,磷的浸出率和pH不再明显变化。另外,碳源质量分数对培养液中磷的浸出率也有影响,质量分数过高或过低均会降低磷的浸出率。  相似文献   

7.
为了阐明改性钢渣陶粒应用于水体除磷的可行性,通过吸附实验研究了镧铁复合氧化物改性钢渣陶粒对低浓度磷的吸附特性,考察了投加量、pH、共存离子等因素对除磷率的影响,并研究其吸附动力学特性。采用NaOH作为再生剂,比较了吸附饱和的改性钢渣陶粒经不同条件再生处理后的除磷效果。结果表明,对于初始磷浓度1 mg/L的溶液,吸附剂投加量5 g/L,pH为7时,除磷率高达99.07%;HCO_3~-和SO_4~(2-)对除磷的抑制作用较强。吸附动力学过程符合准二级动力学模型。使用1.5 mol/L NaOH浸泡60 min是较为合理的再生条件,一次再生后的除磷率仍可达98.51%。  相似文献   

8.
使用丙酸-乳酸体系化学镀低磷Ni-P合金,研究了镀液中镍与磷的浓度比、乳酸、丙酸、pH对镀速和磷含量的影响,并得到了最佳低磷化学镀Ni-P合金工艺。实验结果表明,提高硫酸镍与次磷酸钠的质量浓度比和pH,降低乳酸和丙酸的质量浓度,有利于得到低磷化学镀Ni-P合金层。  相似文献   

9.
对4A沸石结构、性能和配伍性进行了研究,通过正交试验,筛选出低磷、无磷洗衣粉配方,并结合工艺条件进行了改进。解决了洗衣粉成型差、颗粒易破碎、风送管道易堵塞等问题。经测试,灰分沉积率与普通粉无明显差别。用4A沸石作为五钠的代用品生产的低磷、无磷粉具有显著的社会经济效益。  相似文献   

10.
冼昶华 《化工时刊》2008,22(3):29-31
采用天然高分子聚合物壳聚糖对含磷废水进行吸附处理,考察了壳聚糖前处理的方式、处理时间、pH值、壳聚糖用量等条件对吸附率的影响,得出壳聚糖前处理最佳pH值为2.0;处理的水样pH值为6.0—6.2时,吸附磷的效果最好;最佳处理时间为40—50min,吸附率达到74.14%,吸附量为0.342mg/g。动态解吸,回收率可达91.84%。壳聚糖还可以进行再生,再生利用率为94.34%,同时还探讨了该方法在实际中的具体应用。  相似文献   

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12.
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.  相似文献   

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14.
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.  相似文献   

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17.
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.  相似文献   

18.
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.  相似文献   

19.
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.  相似文献   

20.
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。  相似文献   

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