石灰法分解钠硼解石制备硼酸钙

以钠硼解石天然矿粉为原料,消石灰为分解剂,经分解、过滤、洗涤及干燥制备出硼酸钙(CaO·B2O3·6H2O)产品.实验研究确定了适宜的工艺条件,即硼钙配料比m(B2O3):m(CaO)在1.6:1左右,液固比为3.2:1左右,温度25℃,反应时间5～6 h.在此工艺条件下制得的硼酸钙产品含B2O3 40%～42%、CaO 27%～30%,可以作为玻璃纤维工业的含硼原料使用.     

硬脂酸钠改性白硼钙石的水热合成及表面改性

以硼酸和氢氧化钙为原料,在硼酸和氢氧化钙物质的量比为4:1和反应温度160℃的条件下,水热反应4 h合成出一种硼酸钙.对合成产物进行了化学成分、X射线衍射、粒度、热重、扫描电镜等表征,结果表明产物为单一物相的白硼钙石(4CaO·5B2O3·7H2O).以硬脂酸钠为改性剂对白硼钙石进行湿法改性,考察了硬脂酸钠的用量等因素...     

由硼砂和消石灰制备偏硼酸钙

以硼砂和消石灰为原料,经反应、过滤、洗涤及干燥制备出偏硼酸钙(CaO*B2O3*6H2O)产品.经过实验研究确定了适宜的工艺条件:硼钙配料比(氧化硼与氧化钙质量比)在2.2∶ 1左右;液固体积质量比为2.76 mL/g左右;温度为35 ℃;反应时间为8～10 h.在此工艺条件下制得的偏硼酸钙产品含氧化硼质量分数为29%～31%、氧化钙质量分数为23%～25%、氧化钠质量分数≤0.5%.产物的X射线衍射分析和热重分析表明,合成的产品为六水合偏硼酸钙纯相,扫描电镜显示产物为白色的不规则六边形条状晶体.     

有关棚酸盐的术语和用途

术语：棚一非金属元素。元素周期表第五个元素,元素符号B、原子量10．8。在自然界中硼常与氧和其它元素共生,以钢、钙最为普遍。氧化硼-B2O3,由硼酸脱水而成。物质中的棚含量通常用B2O3的百分比来表示.硼酸一硼酸盐与酸反应的产物,分子式为H3HO3。硼酸盐-含氧的硼化合物的统称。硼砂-天然或精炼得到的十水四硼酸钠（Na2B4O7·10H2O）。这一名称也用于五水硼砂（Na2B407,.5H2O）和无水硼砂（Na2B4O7).硬硼钙石-钙硼酸盐矿。用来生产硼酸、玻璃、陶瓷和搪瓷釉料的熔剂原料。水方硼石-钙镁硼酸盐。也是用来生产玻璃。陶瓷和搪瓷釉…     

二水偏硼酸钙的湿法改性及表征

以硼酸和氢氧化钙为原料,在常温常压下合成六水偏硼酸钙,对合成产物进行了化学成分、X射线衍射分析表征,结果表明产物为单一物相的六水偏硼酸钙(CaO·B2O3·6H2O).在140℃下烘干3h得到二水偏硼酸钙(CaO·B2O3·2H2O).以硬脂酸钠、油酸为改性剂对二水偏硼酸钙进行湿法改性,考察了硬脂酸钠、油酸的用量、改性时间、改性温度等因素对二水偏硼酸钙湿法改性的影响.对改性产物进行了红外光谱、活化指数和接触角表征.结果表明:在硬脂酸钠用量为5％,二水偏硼酸钙在60℃下改性反应60 min,改性产物的活化指数可达95.27％,接触角为106.3°,改性效果明显;在油酸用量为5％,二水偏硼酸钙在90℃下改性反应90 min,改性产物的活化指数可达到95.79％.     

重要的化工原料硼酸钙

硼酸钙有二元二硼酸钙(CaO·B_2O_3·nH_2O)、二元四硼酸钙(CaO·2B_2O_3·nH_2O)、四元六硼酸钙(2CaO·3B_2O_3·nH_20)和二元六硼酸钙。它广泛应用在玻璃、陶瓷、搪瓷和釉行业,尤其在无碱玻璃纤维中是唯一无氟、低镁,铁甚微的一种重要的化工原料。在无碱玻璃纤维中的硼,长期来自硼酸,而硼酸用量费用占原料总价的70～80%,不仅增加了生产成本,而且还因硼酸的挥发而污染了工作环     

过硼酸钙的合成研究

以硼砂(或硼酸)和氢氧化钙为原料,在m(B2O3)∶m(CaO)=2.3∶1和35℃条件下,合成偏硼酸钙。自然风干的偏硼酸钙与质量分数为30%的过氧化氢在稳定剂存在下,经反应、过滤及干燥制备出过硼酸钙(CaO.B2O3.nH2O2.mH2O,n为1.5~2.5,m为2~3)。SEM分析表明,以硼砂为原料合成的偏硼酸钙晶型更有利于合成过硼酸钙。研究结果表明:在60℃及复合稳定剂Q存在的情况下,当液固比(mL/g)为3.5∶1、反应40 min时,获得的过硼酸钙中w(B2O3)为28%~29%、w(CaO)为22%~24%、活性氧质量分数大于13.5%、w(Fe)≤0.004%。     

五水合六硼酸钙的水热合成及其高温相变研究

在120 ℃的条件下,利用硼酸和石灰进行水热反应制备五水合六硼酸钙（CaB6O10·5H2O）。五水合六硼酸钙的差热分析结果显示,其脱水分4步,在800 ℃和900 ℃附近分别有一个相变放热峰和吸热峰。对五水合六硼酸钙的高温相变行为进行了探讨,化学分析、XRD、TG-DTA 和IR分析结果表明：在600 ℃时,首先发生晶态的五水合六硼酸钙向非晶态的无水六硼酸钙（CaB6O10）转化,至800 ℃时无定型的无水六硼酸钙转变为晶态的无水六硼酸钙,进一步升温至900 ℃时无水六硼酸钙分解为晶态的四硼酸钙（CaB4O7）和玻璃态的三氧化二硼。     

石英光纤表面化学镀镍－磷－硼合金工艺和表征

以镀层表面光亮度和结合力为双目的指标,采用正交试验分别考察了NiCl2·6H2O、NaH2PO2·H2O、KBH4、H2NCH,CH2NH2、3CDSO4·8H2O的含量和温度对石英光纤表面化学镀Ni—P—B合金的影响,并确定了它们的优化条件分别为：24g／L,10g／L,1．0g／L,24mL／L,0．6mg／L和90℃。考察了粗化时间对Ni—P—B合金镀层质量的影响。用扫描电镜（SEM）、体视显微镜（SM）、电感耦合等离子发射光谱仪（ICP—AES）和X射线衍射（XRD）对镀层的形貌、组成和结构进行了表征和分析。结果表明,在选定的光纤表面预处理条件和最优的化学镀条件下,Ni—P－B合金镀层表面平整光亮,结合力好,热震试验后无起泡和脱落发生。     

铝硼硅酸盐硼挥发抑制的初步研究

通过热分析手段研究氧化镧对铝硼硅酸盐玻璃熔制过程中硼挥发量的影响。TG测试结果表明,随着玻璃配合料中氧化镧质量分数的增加,硼挥发量逐渐降低。当La2O3与B2O3摩尔比超过0.2时,这种趋势变化不明显。同时通过XRD分析出了不同热处理机制下,氧化镧和硼酸的混合物的产物在650,℃时,除了La2O3和H3BO3之外,还有新相LaBO3生成;800,℃时,产物为La（BO2）3。与碱土金属硼酸盐相比,La（BO2）3和LaBO3具有更低的饱和蒸汽压,这是硼的挥发量降低的根本原因。     

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.     

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.     

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.     

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.     

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.     

Highly moisture-proof polysilsesquioxane coating prepared via facile sol-gel process

A highly moisture-proof polysilsesquioxane coating was obtained from a new bis-silylated precursor, which was synthesized from 3-aminopropyltriethoxysilane (APTES) and m-xylylene diisocyanate (m-XDI) in tetrahydrofuran (THF) and verified by ¹H MAS NMR. For direct comparison purposes, an SiO₂ coating was also prepared by the Stöber method using tetraethoxysilane (TEOS) as the reactant. Interestingly, the coating obtained from the polysilsesquioxane sol exhibited a much higher moisture resistance capability than its counterpart, which was attributed to its more compact feature between nanoparticles as characterized by N₂ absorption experiment and transmission electron microscopy (TEM). Furthermore, its high transparency of about 92% showed potential for application in the protection of optical crystals.