电泳沉积羟基磷灰石生物陶瓷涂层的研究进展

羟基磷灰石(hydroxyapatite，HAP)生物陶瓷涂层被认为是目前最好的用于替代人体硬组织的一种生物医用材料。电泳沉积是一种全新的涂层制备方法，它可以解决传统HAP生物陶瓷涂层制备工艺上的各种不足。文中综合介绍了国内外有关电泳沉积HAP生物陶瓷涂层的研究报道，概述了电泳沉积的工艺流程和工艺参数，并对各种影响因素全面地进行了详细的探讨，进而提出了相应的设想和展望。     

电泳沉积用羟基磷灰石稳定悬浮液的制备

研究了羟基磷灰石粉体粒径、粉体预烧温度、陈化时间、分散溶剂、悬浮液固含量对羟基磷灰石悬浮液稳定性的影响,通过测定Zeta电位,吸光度等参数表征悬浮液稳定性,对悬浮液电泳沉积的涂层进行SEM表面形貌及粘结-拉伸结合强度的表征.结果表明:悬浮液颗粒越小,Zeta电位越高;对羟基磷灰石粉体预烧800℃,Zeta电位明显提高,且有利于涂层与基体的结合;悬浮液陈化48 h后,颗粒荷电性最佳,可得致密均匀的涂层;以乙二醇为分散溶剂可制备稳定的悬浮液,但乙醇溶剂更有利于涂层的电泳沉积;悬浮液固含量控制为20g/L时,涂层质量较好.     

应用电泳沉积技术制备钛酸钡铁电陶瓷薄膜

采用电泳沉积技术在Pt电极基片上制备BaTiO3铁电陶瓷薄膜，探讨了电泳沉积过程中的控制因素（悬浮液体系，电场强度，料浆浓度，沉积时间等）对成膜性能的影响，并对薄膜材料的结构，性能进行了表征，实验结果表明；在1050℃（2h)的烧成温度下，经重复沉积一烧结2-3次可得到基本无缺陷的BaTiO3陶瓷薄膜，测量频率在1kHz，测量频率在1kHz时，室温（23℃）下的介电常数ε=2300，介电损耗tanδ=0.2。     

均匀沉淀法制备羟基磷灰石的研究

对以硝酸钙和磷酸作为反应物,采用均匀沉淀法制备的羟基磷灰石粉体进行了研究。研究发现,硝酸钙溶液的初始浓度和粉末的煅烧温度对所制备的羟基磷灰石(HAP)的粒径、比表面积有较大的影响。采用XRD射线衍射谱、BET比表面积测试、粒径测试等分析手段,探索出较好的工艺条件,进而探讨了在形成生物陶瓷过程中,煅烧温度对HAP密度及收缩率的影响。     

电泳沉积功能陶瓷涂层技术

本文评述了功能陶瓷悬浮液的稳定性、电泳沉积技术原理、以及该技术在制备生物陶瓷、超导陶瓷、铁电陶瓷、耐磨耐高温陶瓷等功能陶瓷涂层方面的应用。讨论了电流、电压、分散介质及陶瓷本身特性等因素对电泳沉积过程和功能陶瓷沉积层性能的影响。     

电泳沉积制备LaMnO_3/石墨烯薄膜及其光催化性能

采用电泳沉积技术在氧化铟锡(indium tin oxide,ITO)导电玻璃基底上制备出LaMnO3/石墨烯薄膜。通过扫描电子显微镜、透射电子显微镜、X射线衍射、Raman光谱、紫外-可见吸收光谱和荧光光谱等测试手段探讨了电场强度、溶液的浓度、沉积时间等参数对薄膜结构和表面形貌的影响。结果表明,晶粒粒径约为20nm的LaMnO3较均匀地生长在石墨烯片上,且复合膜的厚度受到电场强度、电泳时间和悬浮液浓度的共同作用。光催化性能研究表明,LaMnO3/石墨烯薄膜的光催化活性显著优于纯LaMnO3薄膜,且还原氧化石墨烯的含量为2%时,该薄膜的光催化性能最好,3h内对直接绿的脱色率达到了98.8%。     

钛合金表面电泳沉积氟羟基磷灰石涂层

采用沉淀法制备了氟掺杂的氟羟基磷灰石(FHA,Ca_(10)(PO_4)_6OH_(2–x)F_x(x=0~2))粉体,并采用电泳沉积在钛合金(Ti_6Al_4V)表面制备了FHA涂层。通过改变沉积电压、时间及电极间距获得不同沉积量的涂层,采用X射线衍射、扫描电子显微镜研究了电压、时间、电极间距以及热处理对涂层形貌、物相组成和涂基结合强度的影响,确定制备FHA涂层的最佳沉积工艺和热处理制度。结果表明:控制沉积电压15 V、沉积时间1 min、电极间距1 cm的条件下沉积涂层并在N_2气氛下900℃保温1 h热处理可制得涂层质量好,涂基结合强度高的FHA生物陶瓷涂层。     

电泳沉积磷灰石生物陶瓷涂层的研究进展

羟基磷灰石(HA)生物涂层材料是最有发展前途的生物硬组织替代材料之一.电泳沉积具有装置简单,操作方便,非线性,沉积温度低等特点,可以解决传统HA生物陶瓷涂层制备工艺上的各种不足.文中探讨了电泳沉积的各种工艺影响因素,综合介绍了国内外有关电泳沉积HA复合(梯度)生物涂层和电泳沉积与其它方法复合制备HA生物涂层的研究报道,进而提出了相应的设想和展望.     

C/C复合材料表面羟基磷灰石/聚丙烯酰胺梯度复合涂层的制备与表征(英文)

以丙烯酰胺单体和声化学法制备的纳米羟基磷灰石(hydroxyapatite,HAp)粉为原料、异丙醇为分散介质,采用水热电泳聚合沉积法在C/C复合材料表面制备HAp/聚丙烯酰胺(polyacrylamide,PAM)梯度复合涂层。用电导率仪、X射线衍射仪、扫描电子显微镜、能谱仪、Fourier变换红外分析仪和万能材料试验机等对悬浮液的电导率以及涂层的物相组成、结构、断面微观形貌和结合强度进行了研究,结果表明:异丙醇中碘的浓度为8g/L时,所制备的涂层由HAp和PAM两相组成;HAP被包裹在黏度较大的PAM中,涂层表面均匀,涂层与基体之间结合紧密,未发现明显的裂纹;涂层中元素沿基体–界面方向呈梯度分布;涂层与基体结合强度最大值达到19.10MPa。     

电泳沉积法在铁铬铝合金丝网上制备均匀的铝颗粒涂层

在铁铬铝合金丝网上,以电泳沉积制备了铝颗粒涂层,覆铝改性后的金属丝网是制备丝网整体催化剂支撑体的合适材料.考察了乙醇、丁酮两类悬浮液体系中各操作参数对电泳沉积的影响,获得了制备均匀涂层的适宜条件,即:在乙醇体系中,聚乙烯吡咯烷酮0.2%(质量分数),AlCl32.5 mmol/L,铝粉1%(质量分数),电场强度30 V/cm,沉积时间10 min;在丁酮体系中,硝化纤维0.06%(质量分数),正丁胺10%(体积分数),铝粉0.2%(质量分数),电场强度50 V/cm,沉积时间30 min.通过氮气保护气氛下的热处理,使铝颗粒与合金丝以及涂层中铝颗粒之间结合牢固.     

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。