微波消解-ICP-OES法测定“秦美”与“红阳”猕猴桃中的矿物元素

利用HNO3/H2O2湿法微波消解制样、再结合全谱直读电感耦合等离子体原子发射光谱法(ICP-OES),对产自陕西省周至县的"秦美"与"红阳"两种猕猴桃中的矿物元素组成进行了测定与分析。共检出Al、B、Ba、Ca、Cu、Fe、K、Mg、Mn、Na、P、S、Si、Sr、Zn等15种矿物元素,测定结果相对标准偏差为0.05%~9.02%,加标回收率在94.3%~108.6%。     

微波消解-ICP-OES法测定油麦菜中23种矿物元素

通过HNO3/H2O2湿法微波消解制样、再应用全谱直读电感耦合等离子体原子发射光谱法(ICP-OES),对油麦菜中的矿物元素组成进行了全面的分析与测定。共检出K、Ca、Na、P、Mg、S、Al、Si、Fe、Zn、Mn、Sr、B、Cu、V、T、Cr、As、Ba、Pb、Ga、Cd、Co等23种矿物元素,定量结果相对标准偏差在0.15%~13.3%之间,标准样品回收率在89.0%~109.6%之间。实验结果可为油麦菜的应用研究提供基础数据。     

微波消解-ICP-OES法测定胡萝卜中19种矿质元素

利用HNO3/H2O2湿法微波消解制样、再应用全谱直读电感耦合等离子体原子发射光谱法(ICP-OES),对胡萝卜中的矿物元素组成进行全面的分析与测定。定量分析了K、Ca、P、Na、S、Mg、Al、Si、Ba、Zn、Fe、Sr、B、Cu、Mn、V、Pb、Cr、Ti等19种矿物元素,定量结果相对标准偏差在0.15%~10.3%之间,标准样品回收率测定在89.0%~109.6%之间。实验结果可为胡萝卜的应用研究提供基础数据。     

微波消解-ICP-OES法测定莴笋中17种矿质元素

利用HNO3/H2O2湿法微波消解制样、再应用全谱直读电感耦合等离子体原子发射光谱法(ICP-OES),对咸阳地产莴笋中的矿质元素组成进行全面的测定与分析。定量分析了K、S、Ca、P、Na、Mg、Al、Zn、Fe、Ba、Si、Cu、Mn、Sr、B、V、Cr等17种矿物元素,定量结果相对标准偏差在0.12%~8.98%之间,标准样品回收率测定在89.0%~109.6%之间。实验结果可为莴笋的应用研究提供基础数据。     

全谱直读电感耦合等离子体原子发射光谱测定苦荞麦矿物元素

采用HNO3/H2O2湿法微波消解制样,采用全谱直读电感耦合等离子体原子发射光谱法（ICP-OES）,分析测定了苦荞麦中的矿物元素,共检出P、S、K、Mg、Ca、Si、Al、Fe、Na、Zn、Mn、B、Cu、Se、Ti、Cr、Ba、Sr等18种矿物元素。分析结果的RSD值在0.45%～9.09%之间,其中15种元素在5%以内。苦荞麦中所含P、S、K、Mg、Ca、Na等常量元素的质量分数分别为0.21%、0.21%、0.17%、0.098%、0.019%、0.0017%;微量元素Fe、Zn、Cu、Se、Cr、Si、Mn、B、Ti、Ba、Sr、Al等的含量（mg.kg-1）分别为37.4、16.5、3.67、1.38、0.44、121.6、6.90、4.88、0.63、0.22、0.12、49.9。     

藏雪莲水母雪兔子中矿质元素的测定与分析

经HNO3/H2 O2湿法微波消解制样,利用全谱直读电感耦合等离子原子发射光谱法(ICP-OES),分析测定了青藏高原地区产藏雪莲水母雪兔子中的矿质元素.结果显示,藏雪莲水母雪兔子中含有K、Ca、P、Mg、Al、S、Fe、Si、Na、Mn、Ti、Sr、Ba、B、Zn、Cu、Cr等17种矿质元素,定量分析结果相对标准偏差...     

绿萝卜20种矿质元素的微波消解-ICP-OES测定

利用HNO3/H2O2湿法微波消解制样、再应用全谱直读电感耦合等离子体原子发射光谱法(ICP-OES),对青皮萝卜中的矿物元素组成进行了全面的分析与测定。定量分析了K、S、Ca、P、Na、Mg、Al、Zn、Si、Fe、Ba、Sr、B、Cu、Mn、V、Pb、Cr、Cd、Ti等20种矿物元素,定量结果 RSD值在0.26%~10.5%之间,标准样品回收率在89.0%~109.6%之间。实验结果可为萝卜的应用研究提供基础数据。     

微波消解-ICP-OES法测定黑芝麻中的18种矿质元素

采用HNO3/H2O2湿法微波消解制样,利用全谱直读电感耦合等离子原子发射光谱法(ICP-OES),全面详细地分析测定了黑芝麻中的矿质元素,共检出Ca、P、S、Mg、K、Al、Si、Fe、Na、Zn、Se、Sr、Cu、Mn、Ba、B、Ti、Cr等18种矿质元素,RSD值在1.21%～10.1%,其中13种元素在5%以内。黑芝麻中所含人体常量元素Ca、P、S、Mg、K、Na等的质量分数分别为1.79%,1.08%,0.59%,0.43%,0.41%和0.009 1%;微量元素Fe、Zn、Se、Cu、Mn、B、Cr、Sr、Si、Al等的含量分别为18.6,4.55,3.87,1.74,1.62,0.91,3.21,78.8,125.8 mg/100 g,未检出Pb、Hg、Cd、As以及Ni、Co、Mo等元素。     

微波消解-ICP-OES法测定肉苁蓉中矿质元素

经HNO3/H2O2湿法微波消解制样,利用全谱直读电感耦合等离子原子发射光谱法(ICP-OES),测定了青藏高原地区产肉苁蓉中的矿质元素。结果显示,肉苁蓉中含有Na、K、Ca、P、S、Mg、Si、Al、Fe、Li、Ti、Sr、Mn、Zn、Cu、Ba、B、Cr等18种矿质元素。测定结果相对标准偏差RSD值在0.85%～12.6%,其中14种在5%以内。常量元素中,Na、K、Ca、P、S、Mg的质量分数分别为4.03%,1.23%,0.31%,0.32%,0.29%,0.17%;微量元素中,Fe、Mn、Zn、Cu、Cr含量分别为788.3,16.87,15.29,7.18,1.24 mg/kg。     

微波消解-ICP-OES法测定岷县当归中的矿质元素

采用浓HNO3/H2O2混合酸体系,以微波消解法对岷县当归样品进行前处理,利用全谱直读电感耦合等离子体发射光谱法(ICP-OES法),对样品中矿质元素的组成及含量进行了测定和分析。结果表明,从岷县当归中检测出15种矿质元素,分别为K、Na、Al、B、Ba、Ca、Fe、Mg、Mn、P、S、Si、Sr、Zn、Cr,其中常量元素有K、Ca、Mg、P、S,微量元素有Al、B、Ba、Fe、Mn、Si、Sr、Zn等,未检测出Tl、Ti、Sn、Cu等元素,以及Pb、Cd等重金属元素,15种元素的RSD值在1.01%~19.01%。研究结果可为岷县当归食用药用价值的进一步开发利用提供一定的理论和科学依据。     

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.     

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.