羟基磷灰石分解和恢复的研究

以羟基磷灰石（HA）为研究对象，研究了其在加热过程中相的分解以及冷却过程和不同气氛的后期热处理对HA相恢复的作用。结果显示：当温度从800℃升高至1200℃，伴随着结晶程度的升高，HA逐渐脱去羟基并转变成缺氧羟基磷灰石（OHA），大约在1200℃左右，缺氧羟基磷灰石发生分解，分解相为磷酸四钙（TTCP）和磷酸三钙（TCP）。慢冷和后期湿气热处理有利于分解相的恢复。在二氧化碳气氛中进行后期热处理时，碳酸根能进入到HA的晶格中，形成以A型替代为主的碳酸羟基磷灰石。     

相组成对TiO_2薄膜生物活性的影响(英文)

以钛酸正丁酯(Cl6H36TiO4)为原料,采用溶胶-凝胶法制备了TiO2薄膜。TiO2薄膜分别在300,400,500,600,800℃下于空气中热处理2h。将热处理前后的TiO2薄膜浸泡于模拟体液(simulated body fluids,SBF)中,考察其表面诱导类骨磷灰石形成的能力。利用X射线衍射、扫描电子显微镜、能谱仪、Fourier变换红外光谱等测试手段表征TiO2薄膜和磷灰石的微观结构。结果表明:原始和经300℃热处理的TiO2薄膜为无定形结构;随着煅烧温度的升高,TiO2由无定形结构向锐钛矿相转变;温度升高至800℃后,锐钛矿相完全转化为金红石相。TiO2薄膜经SBF浸泡7d后,经400,500,600,800℃热处理的TiO2薄膜表面生成含有碳酸根的羟基磷灰石,且其Ca与P的摩尔比为1.52,接近人体骨骼的钙磷比(1.67)。而原始和经300℃热处理的TiO2薄膜无此现象发生,这说明TiO2薄膜的晶型对其生物活性具有重要影响,锐钛矿和金红石相TiO2薄膜均具有诱导磷灰石生成的能力。     

高纯超细羟基磷灰石粉末的合成

研究了湿式法配合适当的热处理工艺制备高纯超细羟基磷灰石的过程，考察了溶液ｐＨ值，溶液Ｃａ／Ｐ摩尔比，反应时间，热处理温度的影响，合成的羟基磷灰石粒子纯强度高，颗粒细小而均匀，晶型完整，可以用作制备生物陶瓷的原料。     

模板剂对共沉淀法合成纳米羟基磷灰石粉体形貌的影响

采用共沉淀法,以Ca(NO3)2.4H2O和(NH4)2HPO4为反应体系,分别添加硫酸软骨素、琼脂糖和天门冬氨酸作为模板剂,引入生物矿化作用,合成了不同形貌的纳米羟基磷灰石粉体。采用X射线衍射法和透射电子显微镜分析了合成产物的晶相结构和粉体形貌。结果表明3种模板剂作用下合成的样品都是纯相的纳米羟基磷灰石。在添加硫酸软骨素(≥0.2%,质量分数,下同)或琼脂糖(1.0%)的条件下,当反应体系钙磷比(钙与磷的摩尔比)为1.67,反应pH值为11.0,纳米羟基磷灰石的形貌分别是梭形短片状和纤维丝状。当天门冬氨酸浓度为2.0%时,若反应体系钙磷比为1.62,反应pH值为10.0,其形貌为类球状;若反应体系钙磷比为1.72,反应pH值为8.5,其形貌则为片状。     

山梨醇辅助下羟基磷灰石晶须的水热制备

羟基磷灰石(HA)晶须具有较低的位错密度,较高的抗拉性能,可用作生物陶瓷的增韧材料.以四水硝酸钙和磷酸氢二铵为原料,在水热条件下,通过控制反应温度及时间,制备了羟基磷灰石晶须.借助X射线衍射仪(XRD)、透射电子显微镜(TEM)及傅里叶变换红外光谱仪(FT-IR),对羟基磷灰石的晶相组成、形貌、大小及化学组成进行了表征.研究结果表明:当前驱物钙磷物质的量比为1.67时,以尿素和山梨醇为辅助试剂,在水热条件下,可制得结晶度高、形貌均一、长径比相对较大的羟基磷灰石晶须.     

纳米羟基磷灰石的合成工艺研究

羟基磷灰石是一种重要的骨引导生物材料.以四水硝酸钙和磷酸二氢铵为原料,在一定pH条件下,以三乙醇胺为分散剂,采用化学共沉淀法制备纳米羟基磷灰石,并考察了反应温度、滴加速度、煅烧温度、正丁醇处理对羟基磷灰石的影响.通过FT-IR,XRD,SEM等手段,对粉体化学组成、晶相和形貌进行表征和分析.研究结果表明,在体系反应温度为70℃、磷酸二氢铵滴加速度为3.33 mL/min、煅烧温度为800 ℃时,得到粒径为8～15 nm的高纯度羟基磷厌石纳米材料;用正丁醇处理后,团聚现象得到明显改善.     

磷灰石/硅灰石生物玻璃基骨水泥的溶-凝胶法制备及性能

为了获得高性能的玻璃摹骨水泥,采用溶胶-凝胶法制备了磷灰石/硅灰石(apatite/wollastonite,AW)生物玻璃,将其作为固相粉末与柠檬酸固化液均匀混合制得了AW玻璃基骨水泥(glass-based bone cement,GBC),探讨了溶胶-凝胶法制备的AW生物玻璃作为GBC固相粉末的可能性.用X射线衍射、红外光谱和强度测试仪对不同温度热处理的AW生物玻璃粉末的晶相转变以及骨水泥在人体模拟体液中浸泡不同时间后的晶相组成和抗压强度进行了研究.结果表明:AW生物玻璃粉末经700℃热处理后形成了硅灰石和羟基磷灰石晶相,且温度越高晶相越完整;以900℃热处理后的AW生物玻璃粉末作为固相所制备的GBC随着浸泡时间的增加,骨水泥固化体中生成了更多量的CaC03晶体及少量的羟基磷灰石晶体,且此种GBC的抗压强度最大.     

室温固相法制备羟基磷灰石粉体

以磷酸氢二铵、硝酸钙为原料,采用室温固相反应通过850℃热处理制备了羟基磷灰石(HAP)粉末.并应用X射线衍射(XRD)、傅里叶变换红外光谱(FT-IR)、扫描电子显微镜(SEM)和热重差热分析(TG-DTA)等手段对合成羟基磷灰石的物相组成、化学组成、微观形貌、热稳定性进行了表征和分析.结果表明合成的羟基磷灰石形貌规整、分散均匀、热稳定性好,热处理有效控制了粉体的团聚,显著提高了羟基磷灰石晶粒的结晶度.     

撞击流反应器制备纳米羟基磷灰石

在浸没循环撞击流反应器中,以硝酸钙和磷酸钠为原料、乙酰胺为分散剂,采用水热法合成了纳米羟基磷灰石.探讨了影响产品收率的相关因素,确定较适宜的制备工艺条件如下:钙磷摩尔比1.70、硝酸钙与乙酰胺质量比0.60、反应温度40℃、反应时间80 min.并运用回归分析法求出上述几种因素与收率的数学模型.     

模拟体液中仿生羟基磷灰石超细粉的制备及表征

从仿生合成的思路出发,以模拟体液为反应介质,通过磷酸和硝酸钙反应合成了羟基磷灰石(hydroxyapatite,HAP)粉体.利用差热分析、X射线衍射、红外光谱和透射电镜对合成HAP的晶相转变、微观结构和形貌进行了研究,研究了硝酸钙浓度对羟基磷灰石粉体晶相纯度和高温稳定性的影响.结果表明:在模拟体液中合成的HAP粉体不需要热处理就含有较多的HAP晶相,经500℃热处理后转变为纯相HAP,硝酸钙浓度为0.2 mol/I时所合成的HAP具有很好的纯度和高温稳定性,经1 550℃烧结后只有微量α-Ca3(PO4)2析出;所合成的HAP为纳米颗粒,呈现出球状和短棒状形态,接近于人体骨磷灰石.体外生物活性表明:HAP具有较强的诱导Ca,P沉积的能力.     

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。