磁性荧光聚合物载药微球的制备

采用反相微乳液法合成氨基功能化的CdTe-Fe_3O_4/SiO_2磁性荧光复合纳米粒子,通过去甲斑蝥酸钠(SNCID)的羧基与氨基化的CdTe-Fe_3O_4/SiO_2磁性荧光复合纳米粒子孔道表面的羟基形成氢键,制成磁性荧光聚合物载药微球。采用荧光分光光度计(FS)、扫描电镜(SEM)、紫外-可见分光光度计(UV-Vis)、傅里叶红外光谱仪(FT-IR)等方法对该聚合物载药微球的理化性质进行表征分析。结果显示磁性荧光聚合物载药微球为球状,具有良好的分散性和光致发光能力等优点,其载药量和包封率分别为21.49%和69.84%。磁性荧光复合纳米粒子可作为具有荧光性质的药物载体。     

一种Au@Fe_3O_4纳米复合粒子的快速合成方法

团簇状的Au@Fe_3O_4纳米复合粒子采用两步法进行合成。首先通过共沉淀法合成柠檬酸修饰的Fe_3O_4纳米粒子;其次以柠檬酸纳为温和的还原剂将HAuCl_4快速还原为Au纳米粒子而沉积在Fe_3O_4的表面。并考察了HAuCl_4及柠檬酸修饰的Fe_3O_4纳米粒子用量对合成过程的影响。采用紫外-可见分光光度计(UV-vis)、动态光散射仪(DLS)及透射扫描电镜(TEM)等测试手段对所制备的纳米粒子进行了表征。结果表明:当V(1%HAuCl_4)=1.8 m L,m(柠檬酸修饰的Fe_3O_4)=12.5 mg时,Au@Fe_3O_4纳米复合粒子的中心Au纳米粒子的粒径大小为20~50 nm左右而周围包覆的Fe_3O_4纳米粒子的大小为10 nm左右,且其在水中能够稳定的存在3个月而粒径大小无明显的变化。     

Fe3O4-CNTs复合物的制备及载药效果

为充分利用Fe_3O_4和碳纳米管(CNTs)在靶向和载药方面的性能优势,采用化学原位沉积法制备了Fe_3O_4-CNTs磁靶向复合物,并通过物理法分别负载了阿司匹林(ASA)、庆大霉素(GM)和阿霉素(DOX)。通过CNTs上Fe_3O_4纳米粒子沉积情况来优化铁盐与CNTs不同质量比,通过单因素实验考察负载时间、负载温度、原料质量比对Fe_3O_4-CNTs载药量的影响。实验结果表明,当铁盐与CNTs质量比为4.5∶7.0时,Fe_3O_4颗粒均匀生长在CNTs表面,Fe_3O_4-CNTs复合物具有较好磁性;Fe_3O_4-CNTs复合物负载ASA时,在CNTs与ASA的质量比为1∶4、负载时间为120 min、负载温度为40℃条件下,最高载药量为4.85%;Fe_3O_4-CNTs复合物负载GM时,在CNTs与GM质量比为1∶4、负载时间为150 min、负载温度为30℃条件下,最高载药量为45.04%; Fe_3O_4-CNTs复合物负载DOX时,在CNTs与DOX的质量比为1.0∶1.5、负载时间为180 min、负载温度为30℃条件下,最高载药量为17.02%。     

磁性三聚氰胺脲醛树脂的合成及表征

采用聚乙二醇(PEG)将合成的Fe_3O_4纳米粒子进行包覆制备了亲水性磁流体(Fe_3O_4@PEG),采用共沉淀法将Fe_3O_4@PEG与三聚氰胺脲醛树脂(MUFRs)预聚物作用制得磁性三聚氰胺脲醛树脂,并利用X射线衍射仪、傅里叶变换红外光谱仪、扫描电子显微镜等对磁性三聚氰胺脲醛树脂进行了表征。结果表明:合成的Fe_3O_4为纳米粒子;高分子包覆对Fe_3O_4的晶体结构和晶粒粒径没有明显影响;当Fe_3O_4@PEG与MUFRs的质量比为2∶1时,磁流体包覆完整,制得的磁性三聚氰胺脲醛树脂微球外观光滑,球形度好且粒径分布均匀。     

新型磁性吸附材料的合成及表征

水中重金属的脱除是污水处理中的重要内容。吸附法是一种除去水中重金属污染的简单高效的方法。磁性吸附剂具有成本低、无二次污染、吸附率高、便于分离和再生等特点,在污水处理上有着重要的应用前景。本文采用溶剂热法制备磁性Fe_3O_4纳米粒子,考察了外部条件对磁性Fe_3O_4纳米粒子生成的影响,确定了制备磁性Fe_3O_4纳米粒子的最佳条件。制备了Fe_3O_4@SiO_2复合微球,通过将壳聚糖键合到颗粒表面并接枝三乙烯四胺改性,得到氨基修饰的磁性Fe_3O_4纳米粒子。     

高磁含量PLA/Fe_3O_4复合微球的制备及表征

采用超声乳化和挥发溶剂的物理方法,合成了具有高磁含量聚乳酸/四氧化三铁(PLA/Fe_3O_4)复合微球。系统考察了PLA/Fe_3O_4复合微球的质量分数、Fe_3O_4与PLA的质量比及超生乳化时间等因素对磁性复合微球粒径的影响,利用透射电子显微镜(TEM)、傅里叶变换红外光谱仪(FTIR)、热分析仪(TG)、激光粒度分析仪、综合物理特性测试仪和X射线衍射仪(XRD),对所得产物的形貌、粒径、Fe_3O_4的质量分数及磁性能进行了表征。结果表明,超声时间越长,或PLA和Fe_3O_4的总质量分数越小,或Fe_3O_4含量越高,微球的粒径就越小;制备出的磁性微球中Fe_3O_4的最高含量可达48%,饱和磁化强度为0.136 A·m~2/kg。相比化学聚合方法来说,本方法不仅操作简单而且不会出现单体残留。     

功能化Fe_3O_4纳米粒子去除水中Cu~(2+)的研究

本文通过水热法合成了Fe_3O_4磁性纳米颗粒,采用3-氨丙基三甲氧基硅烷(APTMS)对Fe_3O_4颗粒进行表面修饰,得到氨基化磁性微粒,并表征其性能。并用氨基化Fe_3O_4磁性纳米粒子构建铜离子吸附体系。实验结果表明,Fe_3O_4纳米粒子和功能化Fe_3O_4纳米粒子的磁饱和强度值(M)分别为78和59emu·g~(-1)。最终确定的最优工艺组合为:APTMS@Fe_3O_4添加量2mL,温度30℃,吸附时间15min。     

氨基化Fe_3O_4纳米粒子的制备及对胃癌细胞的毒性评价

采用共沉淀法制备了四氧化三铁纳米粒子(Fe_3O_4),并在Fe_3O_4纳米粒子表面修饰上了氨基。透射电子显微镜(TEM)和傅里叶变换红外光谱(FTIR)显示,纳米粒子分散性良好,粒径约为10 nm,氨基成功修饰在了纳米粒子的表面。以胃癌SGC-7901为目的细胞,依据RGR值考察了Fe_3O_4-NH_2纳米粒子的细胞毒性等级,结果显示,在一定浓度范围内,细胞死亡率与Fe_3O_4-NH_2纳米粒子的浓度成正相关,低于51.2μg/m L时,Fe_3O_4-NH_2纳米粒子的细胞毒性相对较小,Fe_3O_4-NH_2纳米颗粒具有较好的生物相容性。     

潜在的T2类造影剂Fe3O4@BSA纳米粒子的合成及性能研究

制备了Fe_3O_4@BSA磁性纳米功能材料,包裹在Fe_3O_4纳米粒子表面的牛血清白蛋白(BSA)主要起到分散剂和稳定剂的作用。通过傅里叶变换红外光谱、X射线衍射、透射电子显微镜及热重分析对合成的Fe_3O_4@BSA纳米粒子进行了表征和分析。结果表明,制备的Fe_3O_4@BSA纳米粒子中BSA质量分数约为18.9%。体外成像结果表明,随着Fe_3O_4@BSA纳米粒子浓度的增加,T2成像信号增强,具有明显的阴性造影效果。于0.5 T外磁场下,测得Fe_3O_4@BSA纳米粒子的横向弛豫率(transverse relaxivity,r2)为148.18 L/(mmol·s)。结果表明,Fe_3O_4@BSA纳米粒子能够作为一种潜在的T2类磁共振成像造影剂。     

P(St-co-MAA)-Fe_3O_4@SiO_2 pH磁性微球的制备与性能研究

首先制备Fe_3O_4磁性纳米粒子,然后接上SiO_2层,最后通过共聚的方法制备磁性聚合物微球,并探索其对蛋白质的吸附关系。实验结果表明制备的Fe_3O_4与Fe_3O_4复合微球磁性均很强,而且复合微球对蛋白质的吸附能力很强。     

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。