聚二甲基硅氧烷基上转换材料的制备与光催化应用

将光敏剂四苯基卟啉钯(Pd TPP)和湮灭剂9,10-二苯基蒽(DPA)溶解于甲苯,在Tween 20的乳化作用下与去离子水配制成O/W上转换微乳液;进一步与二甲基硅氧烷共混,将O/W上转换微乳液体系负载于固化后的聚二甲基硅氧烷(PDMS)中,制得基于三线态-三线态湮灭(TTA)机制的PDMS固态上转换树脂材料。在半导体激光器(532nm,60m W/cm2)激发下,固态上转换材料可发射强的绿转蓝上转换荧光,固态上转换效率最大可达22%。将该材料应用于光电流响应和光催化降解过程中:三电极体系在PDMS固态上转换树脂上转换荧光的照射下,获得了0.9μA的光电流,证明了光电流的产生源于上转换蓝光对ZnCdS薄膜的照射;Pt/WO3粉末存在和固态上转换蓝光照射的条件下,罗丹明B染料降解作用显著,最大光降解效率达到82.3%。     

固态上转换材料制备及其性能

以聚二甲基硅氧烷(PDMS)为固态介质,将PDMS浸泡于光敏剂四苯基卟啉钯(Pd TPP)和发光剂9,10-二苯基蒽(DPA)的甲苯溶液中,干燥后得到上转换固态树脂(Pd TPP/DPA/PDMS)。利用紫外吸收光谱仪、稳态-瞬态荧光光谱仪和半导体激光器考察了液态(Pd TPP/DPA/甲苯)和固态(Pd TPP/DPA/PDMS)两种体系的上转换效率(Фuc)及在空气中的稳定性。结果表明,在相同条件下(半导体激光器发射波长532 nm,功率密度60 m W/cm2),固态上转换效率最高可达26.3%,固态树脂在空气中保持22%的上转换效率可持续在10 h以上,而液态二元体系在空气中保持22%的上转换效率只能持续2 min。     

固态上转换材料制备及其性能研究

摘要：有机上转换（UC）是一种通过双光子机制将低能量（长波长）的光转换为高本文尝试选择固态聚合物聚二甲基硅氧烷（PDMS）为基质,将光敏剂四苯基卟啉钯（PdTPP）和发光剂9,10-二苯基蒽（DPA）分散其中,制得了固态上转换材料（PdTPP/DPA/PDMS）,有效隔绝了空气中的氧气对光敏剂与发光剂三线态的淬灭,在空气气氛中固态上转换的稳定时间可延长至10 h以上;更重要的是,其上转换效率（uc）最高可达26.3%,这是目前文献报道的最高值。     

O/W型微乳液应用于三线态湮灭上转换介质研究

光子上转换是吸收低能量（长波长）的光发射高能量（短波长）光的过程,在太阳能光伏、光催化等领域具有潜在应用价值而受到广泛研究,然而通常介质采用有机溶剂及绝氧处理都大大限制了上转换的实际应用.本文报道了可用于三线态湮灭上转换过程的新介质-O/W型微乳液,该体系制备简单、无毒环保,无需除氧脱气条件下,上转化发光稳定,具有未来实际应用的潜力.     

微乳液的微观结构与稳定理论（第二讲）

一、微乳液的微观结构1．W/O型结构根据微乳液的假相模型（1），W/O型微乳液由油连续相、水核及表面活性剂与助表面活性剂组成的界面膜三相构成。W/O型微乳液微观结构示意图（2），见图1a。半径为Rw的水核内仅含水及少量溶于水的醇（助表     

环糊精增强金属卟啉/蒽衍生物上转换及其应用

以2-氯-9,10-二甲苯基蒽(DTACl)为发光剂,分别与不同的光敏剂[四苯基卟啉钯(PdTPP)和四苯基卟啉铂(Pt TPP)]构成二元体系(PdTPP/DTACl和Pt TPP/DTACl),并用不同的环糊精(a-CD、b-CD或g-CD)包络发光剂,构成光敏剂/发光剂/CD三元体系。利用紫外分光光度计、荧光光谱仪、二极管泵浦固态激光器、色度计对二元体系及三元体系进行了光谱性能测试,考察了光敏剂的三线态寿命和环糊精包络效应对上转换效率的影响。结果表明,在532 nm低功率(60 m W/cm2)半导体激光器激发下,PdTPP/DTACl和Pt TPP/DTACl体系的上转换效率分别达10.33%和7.15%;PdTPP的三线态寿命(9.63ms)长于Pt TPP的三线态寿命(6.41ms)。在PdTPP/DTACl体系中加入b-CD,上转换效率可提高至12.82%;将获得的蓝光上转换PdTPP/DTACl/b-CD辐照香豆素水溶液(Pt/WO3半导体为催化剂),20 min后即出现7-羟基香豆素的荧光发射峰(469 nm),表明蓝光上转换PdTPP/DTACl/b-CD可催化香豆素转化为7-羟基香豆素。     

十六烷基三甲基溴化铵-珍珠粉相互作用及其稳定乳液的双重相转变

系统研究了阳离子表面活性剂十六烷基三甲基溴化铵（CTAB）对生物质颗粒珍珠粉制备Pickering乳液的类型、微观结构的影响，同时解析了CTAB/珍珠粉稳定乳液从O/W型到W/O型再到O/W型的双重相转变现象。通过分散性观察、Zeta电位的测定、三相接触角和珍珠粉的荧光标记等手段深入剖析了CTAB与珍珠粉颗粒之间的相互影响。结果表明，在未添加CTAB和CTAB浓度较低时（0.01 mmol/L）时，珍珠粉能单独形成O/W型的Pickering乳液，乳化粒子为非球形且有一定聚结。当CTAB的浓度增加到0.05和0.20 mmol/L时，CTAB在珍珠粉表面吸附增强了颗粒的疏水性，润湿性的变化导致乳液类型从O/W型转变到W/O型，此时乳液的微观结构为球形，且尺寸分布较窄。随着CTAB浓度的进一步增加到0.90 mmol/L,CTAB在油水界面上取代吸附的珍珠粉颗粒，荧光显微镜观察验证了此时形成的O/W型乳液是由过量的CTAB来稳定。即通过简单地增加阳离子表面活性剂CTAB的浓度，就能实现乳液从O/W型到W/O型，再到O/W型的双重相转变。     

在微乳液形态下制备含氟聚合物的方法及设备

正1种在微乳液形态下制备含氟聚合物的方法,包括以下步骤:1)将纯水、表面活性剂、助表面活性剂、液态含氟单体以及光引发剂在反应容器内充分混合,形成含氟单体和水组成的O/W微乳液;2)将步骤1形成的O/W微乳液置于紫外线灯下照射,引发聚合反应,生成微乳液形态的含氟聚合物,未聚合的液态含氟单体在反应热的作用下转化为气态含氟单体;3)将步骤2中生成微乳液形态的含氟聚合物和气态含氟     

硅橡胶/单壁碳纳米管复合材料的制备与性能研究

以单壁碳纳米管（SWCNTs）作为功能填料，聚二甲基硅氧烷硅橡胶（PDMS）作为基体，采用溶液共混法制备硅橡胶/单壁碳纳米管（PDMS/SWCNTs）复合材料。研究了SWCNTs对PDMS/SWCNTs复合材料导电性能、力学性能、导热性能及流变性能的影响。结果表明：与纯硅橡胶相比，少量SWCNTs(0.67%)的加入使PDMS/SWCNTs复合材料的电导率提高13个数量级，达到1.16 S/m，热导率达到0.322 W/（m·K），拉伸强度达到10.6 MPa。PDMS/SWCNTs复合溶液的流变行为符合双Arrhenius化学流变模型，可获得不同含量SWCNTs下PDMS/SWCNTs复合溶液的流变学方程，据此能够预测出复合溶液在不同温度和时间下的黏度，为橡胶复合材料的成膜工艺提供一定的数据基础。     

硫酸钡微/纳结构材料的微乳液合成与形貌控制

在十六烷基三甲基溴化铵（CTAB）/环己醇/水三组分体系的水包油（O/W）、油包水（W/O）和油水双连续结构区域,以相应盐的水溶液代替水构成3种典型的微乳液体系,分别制备了不同形貌的硫酸钡微/纳结构材料,并通过透射电镜（TEM）、X射线衍射（XRD）手段对所制样品进行了表征。结果表明,微乳液的结构对形成无机盐晶粒的尺寸和形貌能够产生影响,同时CTAB在晶粒表面吸附可能对晶粒的生长起一定的导向作用。     

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.     

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。     

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.     

基于ATRP法制备的触角状亲水性羟胺树脂的吸硼性能的研究

以大分子引发剂氯乙酰化聚苯乙烯微球(PS-acyl-Cl)经原子转移自由基聚合(ATRP)法引发丙烯酰胺(AM)和甲基丙烯酸缩水甘油酯(GMA)单体的共聚接枝,制得一种触角状亲水性环氧载体(PS-acyl-g-P(AM-co-GMA)),再经二乙醇胺(DEA)的环氧基开环胺化反应,得到一种含多个-NCH2CH2OH螯合配基的多齿-五元螯合环的触角状亲水性羟胺树脂(PS-acyl-g-P(AM-co-GMA)-DEA)。将此树脂用于硼吸附研究,结果表明,PS-acyl-g-P(AM-co-GMA)-DEA树脂对硼的吸附满足Langmuir方程,为单分子层吸附;饱和吸附量约为37.7 mg·g-1,且树脂5 min即可达到吸附平衡,与其它已报道的吸硼树脂相比,该树脂具有更高的吸附量和吸硼速率。吸附动力学研究表明,树脂吸附硼的过程主要由颗粒扩散过程控制。重复使用5次后该树脂的吸附量基本不变,解吸率均在90%以上,重复使用性能良好。