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水载型木材防腐剂中有效成分固着的影响因素 总被引：1，自引：0，他引：1
水载型木材防腐剂在木材防腐市场中占据着主导地位,然而其中的有效成分的抗水流失性差是其存在的主要缺点,这在很大程度上是由于防腐处理材在使用前防腐剂有效成分与木材成分之间的固着反应不充分而造成的,因此提高防腐有效成分在处理材中的固着质量是提高抗流失性的关键.笔者对国内外在水载型防腐剂中有效成分固着方面的研究进行了较为系统、全面的介绍,其中包括木材树种、固着的环境温度与相对湿度、固着时间、木材含水率、防腐剂的保持量、防腐剂成分组成等不同因素的影响,并在此基础上提出了今后的研究方向. 相似文献
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我国CCA系列配方与英国CCA(Tanalith C,Celcure K33)的对比试验表明:我国CCA_3、CCA_6配方抗流失和对金属腐蚀效果接近英国产品;砷含量范围低于美国CCA—C型;国产原料配制的CCA_(S)抗流失和对金属腐蚀性较好。浸渍处理试验显示,CCA类防腐剂宜采用加压法。PPA油性防腐剂中的五氯酚溶解度、抗“霜”、油漆性能良好;CCB宜于处理门窗及室内木结构。表层化学浸渍处理可使硼在木材中的保留率提高到60—70%。 相似文献
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J.V. Evans B.V.Sc. B.Sc. A.T. Phillipson M.A. Ph.D. M.R.C.V.S. F.R.S.E. 《New Zealand veterinary journal》2013,61(1):12-14
Extract From the start I want to make it clear that the research work described here is the work of one of us (J.V.E.), and the reason why I am presenting his work is that Evans comes from New Zealand and presented a paper on this subject to the annual meeting of the British Association for the Advancement of Science last September in Sheffield, so that it seemed appropriate that his work should also be presented to this Society. 相似文献
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建筑材(木窗)防腐处理应用性试验表明:防腐剂PPA,CCB和CCA_(S)可用于门窗材的防腐处理。PPA宜采用双真空法;CCA_(S)、CCB宜采用加压法。其吸药量宜控制在窗框6kg/m~3,扇窗4kg/m~3。处理前应先机械加工,按窗框和窗扇分类进行防腐处理。对于难处理树种木材应考虑密封堆集扩散作业,使用水溶性防腐剂(CCA_(S)、CCB)时需采取木材防变形措施。 相似文献
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蔬菜移栽机的覆土镇压器设计 总被引：2，自引：0，他引：2
旱地移栽时需要秧苗稳定并牢固的压紧在泥土内,通过覆土镇压器进行覆土和压实,覆土镇压器的研究非常重要。通过受力分析,进行压强及应力计算,确定了主要工作部件的结构和性能参数,满足农艺要求,为小型蔬菜移栽机的设计提供一定的技术支持。 相似文献
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《黑龙江八一农垦大学学报》2012,24(3)
旱地移栽时需要秧苗稳定并牢固的压紧在泥土内,通过覆土镇压器进行覆土和压实,覆土镇压器的研究非常重要。通过受力分析,进行压强及应力计算,确定了主要工作部件的结构和性能参数,满足农艺要求,为小型蔬菜移栽机的设计提供一定的技术支持。 相似文献
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《Veterinary parasitology》2015,207(1-2):140-143
Cryptosporidium spp. is the most important parasitic diarrheal agent in the world, is among the top four causes of moderate-to-severe diarrheal disease in young children in developing nations, and is problematic as an opportunistic co-infection with HIV. In addition, Cryptosporidium is a persistent challenge for livestock production. Despite its zoonotic potential, few studies have examined the ecology and epidemiology of this pathogen in rural systems characterized by high rates of overlap among humans, domesticated animals, and wildlife. To improve our understanding of the zoonotic potential of Cryptosporidium species in the rural tropics, we screened humans, livestock, peridomestic rodents, and wildlife using PCR-RFLP and sequencing-based approaches to distinguish species of Cryptosporidium in rural southeastern Madagascar. Cryptosporidium of multiple species/genotypes were apparent in this study system. Interestingly, C. suis was the dominant species of Cryptosporidium in the region, infecting humans (n = 1), cattle (n = 18), pigs (n= 3), and rodents (n = 1). The broad species range of C. suis and the lack of common cattle Cryptosporidium species (Cryptosporidium parvum and Cryptosporidium andersoni) in this system are unique. This report represents the fifth confirmed case of C. suis infection in humans, and the first case in Africa. Few rural human and livestock populations have been screened for Cryptosporidium using genus-specific genotyping methods. Consequently, C. suis may be more widespread in human and cattle populations than previously believed. 相似文献
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建立了超高效液相色谱(UPLC)法同时测定水性胶黏剂中甲醛、乙醛和丙烯醛的分析方法.水性胶黏剂采用去离子水进行振荡萃取,在酸性条件下,经2,4-二硝基苯肼(DNPH)衍生化后,采用ACOUITY UPLC(R)BEH C18 2.1 mm×100 mm(1.7 μm)柱为分离柱,以乙腈-水为流动相,采用优化后的条件二极管阵列检测器进行检测,分析时间为8.0 min.结果表明,甲醛、乙醛、丙烯醛的回收率分别为:100.66％、96.57％、99.56％,相对标准偏差为2.1％～3.4％;该方法分析时间短、流动相消耗量少、结果准确可靠,适合于水性胶黏剂中甲醛、乙醛和丙烯醛的快速测定. 相似文献