陶瓷材料计算机配色方法的探讨与实践

以牙科陶瓷为例探讨了陶瓷材料计算机配色的方法和机理,建立了牙科陶瓷计算机配色数据库,通过实验对数据库进行了修正,分析了配色不准的原因并提出了解决办法.     

锆钒黄色料的改进与研究

一、前言: 锆钒黄陶瓷颜料是一种锆基陶瓷颜料。传统的锆钒黄通常是由ZrO_2和V_2O_5混合煅烧而成,这种配方一直延用至今。但是,近几年来化工原料涨价,颜料成本提高,为此我们查阅有关资料,进行了初步试验。二、锆钒黄色料的改进依据: 锆基陶瓷颜料按着色元素在颜料中的分布状态有:固溶型、吸附型和包裹型三种,     

迷彩伪装涂料的计算机辅助配色研究

以Kubellk—Munk理论和颜料的光学叠加特性为基础，建立了计算机辅助可见近红外（380～1200nm）全光谱双参数配色模型和计算方法。该模型可以有效地进行迷彩伪装涂料的配方设计。应用XYZ色度系统和CIE1976 L^＊a^＊b^＊均色空间两种色彩空间理论实现了光谱反射率向色差和亮度的转化。     

锆系色釉的调色试验

采用三组分配釉调色方法,通过对锆铁红、镨锆黄、钒锆蓝三种锆系色釉的配色试验.说明改变其三组分的比例关系,可得到多种不同颜色的系列色釉.     

关于几种常见色料在透明熔块和锆白熔块中出现色差的控制

常见的几种陶瓷颜料主要有锆系列的镨黄、尖晶石系列的无钴黑和铁铬锌系列的棕色等。一般来说,在高温条件下,哑光釉料中色料的发色趋势与在透明熔块中的发色基本上是一样的。特别是在调色过程中可以发现,大部分的陶瓷色料如果在高温的生料釉中有较好的发色和稳定性,那么它在低温的透明等熔块中的发色会更加好。当前国内陶瓷市场不景气,在部分产区出现停窑的情况下,大中型陶瓷色釉料企业都开始把重心放在出口市场上,而国外客户通常都会要求使用两种以上的釉料进行产品检测,特别是国内的色釉料企业一般出厂检测都只使用一种或者两种釉料,因而造成货物到达对方工厂后出现色差等质量问题。因此,国内陶瓷色釉料企业在出口货物的调色过程中不光是使用对方的釉料进行检测,还应在高温哑光和锆白熔块中进行2次检测,以保证产品在各种釉料中发色稳定。由于陶瓷颜料都是由多种化工原材料进行煅烧合成的,因此,所使用的釉料中的某些成分会对色料产生一些影响。例如,在锆白熔块中含锆的镨黄等系列产品的发色饱和度比在低温的透明熔块中要好。在高温的哑光生料釉中,如果配方中含有氧化锆成分也是会促进锆系列陶瓷颜料的发色的。另外陶瓷色料配方中的原材料以及一些关键的化学元素也会对色料在釉料中的发色产生较为明显的影响。特别是在镨黄的调色过程中,镨黄产品在低温的透明熔块中有较好的呈色力,但是在锆白熔块和高温哑光的釉料中发色饱和度和色调有较大的改变,其饱和度会明显地降低。棕色系列也是容易出现色差的陶瓷色料系列之一。例如红棕色料在低温的透明熔块中可以有较好的发色,但是在锆白熔块中,各家色料企业生产的产品发色有较大的差异性。特别是在色调和发色饱和度方面,红棕产品在低温透明和锆白熔块中的发色趋势有一定的差异性,部分厂家生产的红棕产品在锆白熔块中没有发色或者发色非常浅。这些主要和红棕产品的配方原材料有直接的关系,与后期的调配没有根本性的改变。红棕系列产品中的氧化铬对产品在高温哑光釉料和锆白熔块中的发色起到关键的影响作用。     

等离子分解锆英石合成锆镨黄

利用等离子分解锆英石原料成功地合成出了锆谱黄陶瓷颜料，讨论了各工艺参数对颜料合成的影响，优化出了以等离子分解锆英石为原料合成镨黄颜料的最佳工艺制度。     

锆英石型系列陶瓷颜料研制

锆英石型系列陶瓷颜料属于高温陶瓷颜料,包括镨黄、钒兰、铁红、镉红四种。它是目前唯一能产生红、黄、兰三种颜色的同型颜料。它的非常的化学稳定性、高温稳定性,引起世界各国陶瓷颜料化工界重视。同时,由于它们是同型颜料,可实现陶瓷颜料三基色化,大大简便陶瓷色釉的配制。锆英石的化学稳定性及热学稳定性,又大大地扩大其使用范围,以及坯釉的适应性。从结构上而言,锆英石型陶瓷颜料可分二种。一是掺杂型,包括镨黄与钒兰,分别为Pr~(4 )、V~(4 )进入锆英石晶格中取代Zr~(4 )形成的颜料;另一是包裹型,即α-Fe_2O_3和Cd(S、     

利用PDZ合成锆英石陶瓷颜料

利用ＰＤＺ原料成功地合成出了锆钒蓝，锆镨黄，锆铁红陶瓷颜料，讨论了各工艺参数对颜料合成的影响，优化出了ＰＤＺ合成锆英石颜料的最佳工艺制度。     

Zr掺杂对BaTiO3陶瓷微观形貌及性能的影响

采用溶胶-凝胶法制备了锆掺杂的钛酸钡陶瓷,通过XRD、SEM等分析检测手段对所得锆钛酸钡陶瓷样品进行了表征。系统地研究了Zr掺杂对BaTiO_3基陶瓷相组成、微观形貌和介电性能的影响。结果表明,锆钛酸钡陶瓷样品均为单一的立方相钙钛矿结构,晶粒大小均匀,随着Zr掺杂量的增加,陶瓷晶粒尺寸先增大后减小,孔隙逐渐增多,介电常数先增大后减小,介电损耗先减小后增大。     

利用PDZ合成锆英石基陶瓷颜料

利用PDZ原料成功地合成出了锆钒蓝、锆镨黄、锆铁红陶瓷颜料,讨论了各工艺参数对颜料合成的影响,优化出了PDZ合成锆英石颜料的最佳工艺制度。     

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.     

Many Drugs of Abuse May Be Acutely Transformed to Dopamine,Norepinephrine and Epinephrine In Vivo

It is well established that a wide range of drugs of abuse acutely boost the signaling of the sympathetic nervous system and the hypothalamic–pituitary–adrenal (HPA) axis, where norepinephrine and epinephrine are major output molecules. This stimulatory effect is accompanied by such symptoms as elevated heart rate and blood pressure, more rapid breathing, increased body temperature and sweating, and pupillary dilation, as well as the intoxicating or euphoric subjective properties of the drug. While many drugs of abuse are thought to achieve their intoxicating effects by modulating the monoaminergic neurotransmitter systems (i.e., serotonin, norepinephrine, dopamine) by binding to these receptors or otherwise affecting their synaptic signaling, this paper puts forth the hypothesis that many of these drugs are actually acutely converted to catecholamines (dopamine, norepinephrine, epinephrine) in vivo, in addition to transformation to their known metabolites. In this manner, a range of stimulants, opioids, and psychedelics (as well as alcohol) may partially achieve their intoxicating properties, as well as side effects, due to this putative transformation to catecholamines. If this hypothesis is correct, it would alter our understanding of the basic biosynthetic pathways for generating these important signaling molecules, while also modifying our view of the neural substrates underlying substance abuse and dependence, including psychological stress-induced relapse. Importantly, there is a direct way to test the overarching hypothesis: administer (either centrally or peripherally) stable isotope versions of these drugs to model organisms such as rodents (or even to humans) and then use liquid chromatography-mass spectrometry to determine if the labeled drug is converted to labeled catecholamines in brain, blood plasma, or urine samples.     

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.     

Novel polyurethane coating technology through glycidyl carbamate chemistry

Glycidyl carbamate chemistry combines the excellent properties of polyurethanes with the crosslinking chemistry of epoxy resins. Glycidyl carbamate functional oligomers were synthesized by the reaction of polyfunctional isocyanate oligomers and glycidol. The oligomers were formulated into coatings with several amine functional crosslinkers at varying stoichiometric ratios and cured at different temperatures. Properties such as solvent resistance, hardness, and impact resistance were dependent on the composition and cure conditions. Most coatings had an excellent combination of properties. Studies were carried out to determine the kinetics of the curing reaction of the glycidyl carbamate functional oligomers with multifunctional and model amines. Detailed kinetic analysis of the curing reactions was also undertaken. The results indicated that the glycidyl carbamate functional group is more reactive than a glycidyl ether group. Presented at the 82nd Annual Meeting of the Federation of Societies for Coatings Technology, on October 27–29, 2004, in Chicago, IL.