利用高炉渣和粉煤灰制备微晶玻璃热处理制度的优化

以高炉渣及粉煤灰为原料,采用直接烧结法制备废渣微晶玻璃,通过正交试验研究热处理制度对微晶玻璃抗弯强度的影响.结果表明:影响微晶玻璃抗弯性能的热处理制度因素的主次顺序为晶化温度、升温速率、晶化时间和烧结时间.最佳的热处理制度参数为晶化温度970℃、晶化时间1.5h、升温速率5℃·min-、烧结温度1150℃;制备的废渣微晶玻璃主晶相为钙镁黄长石,晶粒形貌呈方块状,晶粒尺寸约2 μm;废渣利用率高,高炉渣利用率达90％,微晶玻璃性能优良.     

镁铝硅系堇青石基微晶玻璃的制备及性能研究

采用高温熔融法制备了MgO-Al2O3-SiO2 (MAS)系堇青石基微晶玻璃.借助X射线衍射仪(XRD)、扫描电镜(SEM)及热膨胀系数仪研究了晶化热处理工艺、MgO/Al2O3质量比以及晶核剂种类(TiO2/ZrO2)与含量对MAS系堇青石基微晶玻璃理化性能和晶化特性的影响.结果表明:在核化温度750℃、保温时间1h,晶化温度1050℃、保温时间2.5h,升温速率5 ℃/min时,微晶玻璃中堇青石含量最高,析晶性能最好;当MgO/Al2O3质量比为1左右时,在30 ～ 700℃温度范围内,平均热膨胀系数最小,在4.4 ～4.8×10-6K-1范围内可调;TiO2是MAS系堇青石基微晶玻璃的有效晶核剂,而ZrO2的加入并不利于基础玻璃的晶化.     

以油页岩渣为原料制备微晶泡沫玻璃

以油页岩渣为主要原料,加入其他辅助原料制备了微晶泡沫玻璃,并分析了各种因素对微晶泡沫玻璃性能的影响.结果表明,发泡剂碳酸钙和稳泡剂磷酸钠的最佳掺量为4%和6%;最佳的工艺条件为:发泡温度1080℃,发泡时间15 min,升温速率14℃/min.试样经过预热、烧结、发泡、稳泡和退火等热处理工艺,完成了发泡和析晶过程.其中发泡工艺需要较高温度,并在短时间内保温.XRD,SEM及FT-IR分析表明,试样已经完全转化为微晶泡沫玻璃,主晶相为普通辉石,次晶相为钙长石,晶体呈纤维状结构且相互交织.与相关材料比较,微晶泡沫玻璃具有机械强度高和质轻保温隔热的优点.     

晶化温度对油页岩渣微晶玻璃抗折强度和耐腐蚀性的影响

以油页岩渣、电石渣为主要原料制备了全固废微晶玻璃。采用DTA、XRD、SEM等测试手段,分析研究了不同晶化温度对油页岩渣微晶玻璃微观结构和性能的影响。结果表明:最佳晶化温度为950℃,得到的微晶玻璃主晶相为绿辉石和硅灰石,次晶相为霓石和普通辉石,微观结构致密,晶粒呈长条状集聚分布,抗折强度为210 MPa,耐腐蚀性能较好。     

烧结法制备粉煤灰微晶泡沫玻璃

利用粉煤灰通过烧结法制备了微晶泡沫玻璃。研究表明,选用碳酸钙作为发泡剂,最佳用量为5%。通过正交实验确定了最佳热处理条件:发泡温度1025℃、升温速率14℃/min、发泡时间30min。通过XRD和SEM研究了微晶泡沫玻璃的析出晶相和显微结构。主晶相为钙长石CaAl2Si2O8,次晶相为普通辉石Ca(Mg,Fe,Al)(Si,Al)2O6。所制得微晶泡沫玻璃综合性能优于泡沫玻璃和粘土砖。     

可切削微晶玻璃电真空的沿面闪络特性

在1350℃保温2h熔融后浇注,经500℃退火制备了55%质量分数,下同)SiO2-6?O3-8.5%(K2O-Li2O)-11.5%Al2O3-4.5%ZNO-9.5%MgO-5%F的基础玻璃,650～750℃保温2h晶化处理后制成微晶玻璃.采用X射线衍射分析微晶玻璃的物相组成,用扫描电镜观察材料的微观结构,考察晶化工艺对材料高电压真空沿面闪络特性的影响,并与A1203陶瓷沿面闪络性能进行对比.结果表明:该材料比Al2O3陶瓷具有更好的沿面闪络特性;在晶化保温时间相同时,随温度升高,微晶玻璃材料的沿面闪络电压降低;在650℃保温2h的晶化处理后,该微晶玻璃具有较优的沿面闪络特性.     

利用钾长石尾矿制备β-硅灰石微晶玻璃的研究

研究了以福建沙县的钾长石尾矿为主要原料，采用烧结法制备矿渣微晶玻璃的可行性；确定了制备β－硅灰石微晶玻璃的配方：尾矿72％，碳酸钙22.7%，氧化锌（起助熔作用）5.3%(质量分数）；玻璃熔化条件：1250℃，保温3h。选取粒度为0.45-0.9mm的水淬玻璃颗粒，采用正交实验法，研究了热处理条件对材料性能的影响，确定了热处理的优化条件：核化温度975℃，核化时间45min，晶化温度1100℃，晶化时间30min，在优化条件下制备的微晶玻璃由2μm的β－硅灰石晶体和玻璃相组成，吸水率为0.16%，Vickers硬度为9.77GPa,且耐酸碱腐蚀性能优良。     

复合废渣微晶玻璃热处理制度的确定与显微结构分析

介绍了以钢渣、粉煤灰、铜尾矿及砂岩为主要原料制备微晶玻璃的方法.利用DTA、XRD、SEM及EDS等方法研究了微晶玻璃的热处理制度;确定其主晶相为透辉石及其晶相组成成分;晶粒形貌为颗粒状,晶粒的尺寸约为0.5μm.实验结果表明:当废渣及工业砂岩引入为90%时,主晶相为透辉石,材料结构均匀致密、性能良好.实验热处理制度工艺参数为:退火温度:550℃,保温1h;晶化温度900℃,保温2h.     

烧结法堇青石微晶玻璃的研制

实验利用廉价的工业原料氧化铝、滑石、粘土等,加入少量添加剂和晶核剂TiO2,采用粉末烧结法制备出了具有低的介电常数、低的热膨胀系数和高的抗折强度等优良性能的MgO-A l2O3-SiO2系堇青石微晶玻璃。样品最佳热处理制度为:核化780℃,保温2h,晶化990℃,保温2h,升温速率3℃/m in。样品析出主晶相为α-堇青石,伴有少量镁橄榄石(Mg2SiO4)、镁铝钛酸盐(MAT)和金红石(TiO2)次晶相。     

CaO-MgO-Al2O3-SiO2系铜尾矿微晶玻璃析晶特征研究

以铜尾矿为主要原料,采用压延法开展玻璃熔制实验制备CMAS系基础玻璃,进行玻璃微晶化及稳定性等方面的研究.利用差热分析(DSC)、X衍射分析(XRD)、扫描电镜(SEM)等方法系统研究了微晶玻璃组分、热处理温度和时间等因素对玻璃析晶的影响.完成了以透辉石(Ca(Mg,Al)(Si,Al)2 O6)为主晶相的微晶玻璃制品实验配方及制备工艺方案,确定了热处理制度为900℃保温2 h的最佳工艺参数,制备的微晶玻璃力学性能优于市场同类产品.     

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.     

Sapindaceae,cyanolipids, and bugs

Scentless plant bugs (Heteroptera: Rhopalidae) are so named because adults of the Serinethinae have vestigial metathoracic scent glands. Serinethines are seed predators of Sapindales, especially Sapindaceae that produce toxic cyanolipids. In two serinethine species whose ranges extend into the southern United States,Jadera haematoloma andJ. sanguinolenta, sequestration of host cyanolipids as glucosides renders these gregarious, aposematic insects unpalatable to a variety of predators. The blood glucoside profile and cyanogenesis ofJadera varies depending on the cyanolipid chemistry of hosts, and adults and larvae fed golden rain tree seeds (Koelreuteria paniculata) excrete the volatile lactone, 4-methyl-2(5H)-furanone, to which they are attracted.Jadera fed balloon vine seeds (Cardiospermum spp.) do not excrete the attractive lactone. Loss of the usual heteropteran defensive glands in serinethines may have coevolved with host specificity on toxic plants, and the orientation ofJadera to a volatile excretory product could be an adaptive response to save time.Mention of a commercial product does not consititute an endorsement by the USDA.     

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.     

ICP-MS法测定地球化学样品中As、Cr、Ge、V等18种微量痕量元素的研究

建立了测定地球化学样品中包括As、Cr、Ge、V等18种微量、痕量元素的ICP-MS方法。地化试样用HF-HNO3混酸分解后,以1 1 HNO3溶解干渣。由于制样不使用盐酸,避免了Cl对As、Cr、Ge、V的质谱干扰。用国家一级地球化学标准物质GBW 07309制备溶液优化仪器工作参数,并用于校准。方法测定限(6s)为:0.007~6.4μg/g,精密度(RSD%,n=12)为:29%~9.4%,经过国家一级地球化学标准物质的分析验证,结果与标准值吻合。方法已应用于国土资源调查的试样分析。     

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.     

2008～2009年世界塑料工业进展

收集了2008年7月～2009年6月世界塑料工业的相关资料,介绍了2008～2009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、环氧树脂、不饱和聚酯树脂)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。