改性聚硅氧烷消泡剂的研究

采用含氢硅油、聚醚为原料,三氟乙酸为催化剂制备了聚醚改性聚硅氧烷,考察了温度、时间、原料质量配比及催化剂加入量对反应及各指标的影响,结合正交试验得出了适宜的制备条件:反应温度为105℃,反应时间为10h,含氢硅油和聚醚的质量比为1∶20,催化剂用量为0.2%。     

聚醚改性有机硅匀泡剂的制备与性能

以高含氢硅油、八甲基环四硅氧烷(D4)、六甲基二硅氧烷(MM)和烯丙基聚醚等为主要原料制备聚醚改性硅油。对影响聚醚改性硅油性能的因素进行了考察,将其作为匀泡剂应用于聚氨酯硬泡和软泡发泡,并对发泡效果和普适性进行了研究。结果表明,采用特定含氢量的低含氢硅油和烯丙基聚醚,硅氢加成的最佳反应条件为:催化剂用量10μg/g,n(Si—H)/n(CC)=1∶1. 4,反应时间2 h,反应温度110℃。该聚醚改性硅油对于硬泡、软泡具有良好的发泡效果和普适性,最佳用量为质量分数2%。     

聚醚改性聚硅氧烷流平剂合成及性能研究

以氯铂酸为催化剂,由含氢硅油与烯丙基聚醚通过硅氢加成反应,制备得到聚醚改性聚硅氧烷流平剂。探讨了含氢硅油含氢量、烯丙基聚醚结构及相对分子质量、催化剂用量以及反应温度对产品流平性能的影响。试验结果表明,使用含氢量为0.18%的含氢硅油,甲基封端EO结构、相对分子质量为1 600的烯丙基聚醚制备得到的流平剂具有较好的相容、流平、重涂、爽滑、光泽及不稳泡特性。     

Si-C型聚醚改性硅油的制备

研究了以烯丙基聚乙二醇甲基醚和低含氢硅油为原料,甲苯为溶剂,自制的催化剂,制备Si-C型聚醚改性聚硅氧烷,较适宜的合成条件为:选择相对分子量为1 000的聚醚,n(硅氢键)∶n(聚醚)=1∶1.2,反应温度90℃,催化剂用量为30×10-6,甲苯用量为总反应体系质量的25%。合成的聚醚改性硅油透明,性能优越,使用范围较广。     

一种聚硅氧烷消泡剂的合成与应用研究

以氯铂酸为催化剂,烯丙醇聚氧乙烯聚氧丙烯醚(FB)、甲基丙烯酸十二烷基酯(LMA)和含氢硅油(PHMS)为原料,制得一种共改性硅油(PMS)。通过正交试验得到优化工艺条件为:n(Si-H)∶n(C=C)=1∶1.20,催化剂用量30μg·g-1,反应温度90℃,反应时间6 h,此条件下转化率达93.45%。采用高速剪切乳化搅拌方式将水相在油相中进行乳化,制备出聚硅氧烷消泡剂,由应用测试得到优化配方为:硅膏质量分数10%,PMS质量分数6%,复合乳化剂(m(Span 60)∶m(Tween 60)∶m(OP-10)=3∶2∶1)质量分数4%,制备出的聚硅氧烷消泡剂稳定性好,其消抑泡性能优于市售同类产品。     

自乳化型聚醚改性有机硅消泡剂的合成及在复膜胶中的应用

以不同含氢量的含氢硅油分别与2种聚醚反应,得到亲水性、疏水性不同的聚醚改性有机硅共聚物,经复配自乳化制得复膜胶用聚醚改性有机硅消泡剂。通过对反应各影响因素的考察,确定了反应的较优条件:n(S—H)∶n(CC)=1∶1.3,反应温度为120℃,反应时间为6 h,催化剂用量为20μg/g。通过对消泡剂进行涂刷及抑泡性测试并对其稳定性的考察,结果表明:固定抑泡组分m(SP018)∶m(SP024)∶m(SP050)=1∶1∶1不变,乳化组m(SE018)∶m(SE024)∶m(SE050)=1∶2∶2,m(抑泡组分)∶m(乳化组分)=1∶1条件下制得的消泡剂稳定且对复膜胶乳液具有较好的消抑泡效果。     

低密度聚氨酯软泡匀泡剂的合成研究

以氯铂酸为催化剂,以低含氢硅油和3种甲基封端的烯丙基聚醚为原料,制得用于低密度聚氨酯软泡的匀泡剂。考察了原料的比例、反应温度、催化剂用量等因素对合成的影响,并对制得的匀泡剂进行发泡试验和性能评价。结果表明,合成匀泡剂适宜的反应温度为100℃,最佳催化剂用量为20~30 mg/kg,低含氢硅油与封端聚醚最佳摩尔比为1∶1.1,Mn分别为500、1200和4000的3种封端聚醚的最佳质量比为30∶50∶20,最佳聚醚封端率控制在80%以上。采用该匀泡剂制得的软泡泡孔细腻均匀,无闭孔,手感良好,综合性能与进口产品B-8123相似。     

聚醚改性有机硅流平剂的合成及表面性能研究

以含氢硅油和烯丙基聚醚为原料,在氯铂酸螯合物的催化作用下,通过无溶剂硅氢加成反应合成了聚醚改性硅油。通过正交实验测定反应的转化率,探讨了反应时间、反应温度、催化剂用量以及反应物比例对反应的影响,并得出较适宜的反应条件为:反应时间为8h,反应温度为130℃,催化剂用量为20μg/g,反应物配比[n(Si-H)∶n(C=C)]为1∶1.2。在该条件下,含氢硅油中Si-H的转化率达94.45%。由此制备的流平剂能有效降低表面张力,且具有优良的流平性能。讨论了含氢硅油与烯丙基聚醚的结构差异对产品的表面性能的影响。     

聚醚改性硅油的合成研究

以六水合氯铂酸为催化剂,烯丙基聚醚(F-6)与含氢硅油为原料,在无溶剂甲苯的条件下,加热反应生成聚醚改性硅油,通过测定硅氢键的残余量来计算反应的转化率。分别研究了催化剂量、温度、烯丙基聚醚(F-6)与含氢硅油的物质的量比对反应转化率的影响,得出了最优化的反应条件为:催化剂的质量分数为1.5×10-5,温度120℃,n(聚醚)∶n(硅油)=1.20∶1.00。实验表明,合成的聚醚改性硅油可以有效降低溶剂型聚氨酯树脂溶液(As)树脂的表面张力,使其由30.4mN/m降到27.0mN/m。     

Si—C型环氧改性硅油的制备

以乙烯基环氧环己烷和低含氢硅油为原料,甲苯为溶剂,在自制催化剂作用下,制备Si—C型环氧改性聚硅氧烷。结果表明,较适宜的合成条件为:选择相对分子量为1 000的低含氢硅油,投料比n(硅氢键)∶n(环氧)=1∶1.2,反应温度90℃,反应时间10 h,催化剂用量为体系总质量的1%,甲苯用量为总反应体系质量的25%。合成的环氧改性硅油透明,性能优越,使用范围较广。     

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.     

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。     

Methyl 2,4,6-decatrienoates Attract Stink Bugs and Tachinid Parasitoids

Halyomorpha halys (Stål) (Pentatomidae), called the brown marmorated stink bug (BMSB), is a newly invasive species in the eastern USA that is rapidly spreading from the original point of establishment in Allentown, PA. In its native range, the BMSB is reportedly attracted to methyl (E,E,Z)-2,4,6-decatrienoate, the male-produced pheromone of another pentatomid common in eastern Asia, Plautia stali Scott. In North America, Thyanta spp. are the only pentatomids known to produce methyl 2,4,6-decatrienoate [the (E,Z,Z)-isomer] as part of their pheromones. Methyl 2,4,6-decatrienoates were field-tested in Maryland to monitor the spread of the BMSB and to explore the possibility that Thyanta spp. are an alternate host for parasitic tachinid flies that use stink bug pheromones as host-finding kairomones. Here we report the first captures of adult and nymph BMSBs in traps baited with methyl (E,E,Z)-2,4,6-decatrienoate in central Maryland and present data verifying that the tachinid, Euclytia flava (Townsend), exploits methyl (E,Z,Z)-2,4,6-decatrienoate as a kairomone. We also report the unexpected finding that various isomers of methyl 2,4,6-decatrienoate attract Acrosternum hilare (Say), although this bug apparently does not produce methyl decatrienoates. Other stink bugs and tachinids native to North America were also attracted to methyl 2,4,6-decatrienoates. These data indicate there are Heteroptera in North America in addition to Thyanta spp. that probably use methyl 2,4,6-decatrienoates as pheromones. The evidence that some pentatomids exploit the pheromones of other true bugs as kairomones to find food or to congregate as a passive defense against tachinid parasitism is discussed.     

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。