化工压力容器设计中的热处理问题分析

随着社会经济的发展和科学技术的进步,我国石油化工行业的生产技术有了稳定的进步,压力容器成为重要的生产工具,热处理问题成为关键。基于此,以化工压力容器设计中热处理问题作为研究对象,分别从通用条件和特殊条件两方面分析化工压力容器设计中需进行焊后热处理的条件,结合实际情况分析化工压力容器设计中焊后热处理的方法。     

热处理钢渣的性能研究

采用热处理优化钢渣,研究了热处理温度对钢渣热处理效果的影响及热处理钢渣的力学性能,探讨了热处理钢渣掺合料对钢渣水泥性能的影响及作用机理分析。研究结果表明:随着热处理温度的升高,生成的胶凝性矿物的量越多,晶体发育越好;相同条件下热处理钢渣力学性能优于钢渣;热处理钢渣添加量30%不会显著降低水泥的强度。     

热处理剑麻/PLA复合材料的制备与力学性能研究

采用真空干燥箱对剑麻纤维进行预处理,并与聚乳酸(PLA)复合制备了剑麻纤维含量为50%的全降解环保型复合材料。研究了真空条件下剑麻纤维热处理温度、热处理时间对剑麻纤维成分、结构和复合材料性能的影响,并通过红外光谱和扫描电镜分析其作用机理。结果表明:在真空条件下,热处理使剑麻结构发生变化,半纤维素降解,改善了界面结合能力,且适宜的热处理温度、热处理时间有利于复合材料力学性能的提高。     

水热处理条件对长链烷烃(n-C10～13)脱氢催化剂条形载体物性的影响

采用正交设计法考察了进水量、进水温度、水热处理温度、水热处理时间对载体孔容、比表面、强度、吸水率、酸度的影响.确定了最佳水热处理条件为:进水量150 mL/h,进水初始温度400℃,恒温温度680℃,恒温时间10 h.以最佳水热处理条件对载体进行水热处理并将载体制备成催化剂,对催化剂进行了活性及寿命评价,评价结果表明该...     

6000m~3球罐的整球热处理和局部辅助技术

在严格执行ASME规范及制造技术要求的前提下,某公司成功地建造了5台6000m~3球罐,实现了走出国门。本文主要从球罐整体热处理和局部热处理辅助方法阐释了球罐热处理技术要点及控制措施。对今后不同体积不同厚度不同材质球罐整体热处理工作及不同资源条件下选用热处理方法都有一定的指导作用。     

低应力Ni-W/Ni叠层微模具的制备与特性

采用UV-LIGA技术和Ni-W/Ni叠层电镀方法,在微喷嘴模具上制备出低应力Ni-W沉积层.研究了热处理条件对低应力Ni-W电沉积层硬度的影响.考察了沉积态及热处理态的Ni-W层、Ni层的耐磨性.结果发现,热处理后Ni-W/Ni叠层微模具界面结合良好,在干摩擦条件下,经过热处理的Ni-W层的耐磨性是Ni层的6倍;在550 ℃、2 h真空热处理条件下,Ni-W电沉积层应力最低,为230MPa,硬度大于950HV.     

低应力Ni–W/Ni叠层微模具的制备与特性

采用UV-LIGA技术和Ni–W/Ni叠层电镀方法,在微喷嘴模具上制备出低应力Ni–W沉积层。研究了热处理条件对低应力Ni–W电沉积层硬度的影响。考察了沉积态及热处理态的Ni–W层、Ni层的耐磨性。结果发现,热处理后Ni–W/Ni叠层微模具界面结合良好,在干摩擦条件下,经过热处理的Ni–W层的耐磨性是Ni层的6倍;在550°C、2h真空热处理条件下,Ni–W电沉积层应力最低,为230MPa,硬度大于950HV。     

银纳米颗粒/玻璃复合材料的吸收光谱特征

利用离子交换结合热处理方法,制备出Ag纳米颗粒掺杂硅酸盐玻璃复合材料。通过改进的Mie理论拟合了不同制备条件下Ag纳米颗粒的吸收光谱,得到了它们的尺寸和体积分数。拟合结果表明:在热处理条件相同时,离子交换时间越长,样品中Ag纳米颗粒的尺寸越大,体积分数越高;在离子交换条件相同时,随着后续热处理时间的延长或温度升高,样品中Ag纳米颗粒的尺寸变大,体积分数提高。相比于空气热处理,氢气热处理可以显著降低样品中Ag纳米颗粒的形成温度和时间。氢气气氛下形成的Ag纳米颗粒小于空气气氛下形成的Ag纳米颗粒,导致其等离子体共振吸收峰相对空气中热处理的样品发生蓝移。     

热处理对阳离子可染改性涤纶结构和染色性的影响——第1报 热处理效果的评定及热处理对阳离子可染改性涤纶分子结构的影响

对加入SIPM(5-磺酸钠间苯二甲酸二甲酯)为第三单体的高压型阳离子可染改性涤纶和加入SIPM为第三单体并加入一定的第四单体的常压型阳离子可染改性涤纶的成品丝进行短时间的补充热处理,研究了热处理条件时纤维结构和染色性的影响。 本文将分三报在本刊发表。在第一报中,报道根据差热分析(DTA)曲线上有效热定型峰的大小和位置与热处理条件(温度、时间、张力)的关系,并借以判断热处理效果。亦报道了以富立叶红外分光光度仪用补偿全反射(ATR)法对阳离子可染改性涤纶经不同条件热处理后分子结构的变化。     

热处理条件对PVA/PAN和PPVA/PAN渗透汽化复合膜分离性能的影响

制备了以聚乙烯醇（PVA）、磷酸酯化聚乙烯醇（PPVA）和活性分离层的PVA／PAN、PPVA／PAN渗透汽化复合膜并用于乙醇－水恒沸混合物的分离。考察了热处理条件对复合膜分离性能及吸附性能的影响。结果表明,复合膜的分离性能主要是由热处理温度决定的,并且,PPVA／PAN复合膜比PVA／PAN复合膜具有更好的分离性能。确定了最佳的热处理条件,对于PVA／PAN复合膜：在403K下,热处理时间不小于4h,对于PPAV／PAN复合膜：在423K下,热处理时间不小于2h。     

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。