HPMo@UiO-66-SO3H用于中碳链结构磷脂的高效合成

以四氯化锆、磷钼酸水合物、1,2,4,5-苯四甲酸和(3-巯基丙基)三甲氧基硅烷为原料,通过原位合成法及接枝共聚法制得了负载磷钼酸的磺酸基功能化UiO-66(HPMo@UiO-66-SO₃H)。采用XRD、FTIR、SEM、EDS、XPS、N2吸附-脱附和TG-DTG对其进行了表征,将HPMo@UiO-66-SO₃H用于大豆卵磷脂与中碳链脂肪酸(辛酸和癸酸)酯交换合成富含辛酸和癸酸的中碳链结构磷脂,通过正交实验优化了反应条件,考察了HPMo@UiO-66-SO₃H的循环利用性。结果表明,HPMo@UiO-66-SO₃H具有介孔结构,并含有大量HPMo和磺酸基活性组分,且组分间的协同作用促进了中碳链结构磷脂的生成;当HPMo@UiO-66-SO₃H含量为大豆卵磷脂、辛酸和癸酸总质量的5%,m(大豆卵磷脂)∶m(辛酸)∶m(癸酸)=1∶10∶10,50℃下反应4 h时,中碳链脂肪酸接入率高达94.31%(辛酸和癸酸接入率分别为44.21%和50.10%);HPMo@UiO-66-S...     

磺酸基功能化C/Si材料催化合成短碳链结构磷脂

通过化学活化有机磺酸前驱体,低温下制备了磺酸基功能化碳/硅材料(C/Si-SO3H),并将其用于大豆卵磷脂与丙酸乙酯或丁酸甲酯催化合成短碳链结构磷脂的反应中,考察了反应温度、反应时间、催化剂用量及循环次数对该酯交换反应的影响.采用FTIR、Raman及Boehm酸含量滴定等手段对C/Si-SO3H进行结构和表面酸性质表征,以建立该催化剂的构效关系.结果表明,C/Si-SO3H表面含有大量Br?nsted酸性位点,因而催化性能较为突出;当催化剂用量为反应原料总质量的7％、40℃反应6 h,短碳链结构磷脂中丙酸或丁酸的接入率高达18.33％或16.23％,且C/Si-SO3H循环利用4次而无明显失活.     

二氧化硅-磺酸固体酸催化大豆油与异丙醇的酯交换反应

通过溶胶-凝胶法制备了二氧化硅-磺酸(SiO2-SO3H)固体酸催化剂,并用于大豆油与异丙醇的酯交换反应制备生物柴油,考察了催化剂的处理温度、异丙醇与大豆油的摩尔比、催化剂用量、正庚烷用量和反应时间对酯交换反应的影响。结果表明,二氧化硅-磺酸(SiO2-SO3H)具有较高的酯交换反应催化活性。确定制备生物柴油的最佳条件如下:催化剂处理温度为120℃、醇油摩尔比为6∶1、催化剂用量(以大豆油质量计)为5.0%、正庚烷用量(以大豆油质量计)为30.0%、反应时间为6.0h。在该条件下,大豆油异丙酯产率可达96.12%。     

短碳链结构磷脂在Zn-Fe3O4@SiO2催化作用下的制备及其性能

通过溶胶-凝胶法和浸渍法制备了负载Zn的二氧化硅包覆四氧化三铁（Zn-Fe3O4@SiO2），采用SEM、TEM、XPS、Py-FTIR、VSM、EDS等对其进行表征。将Zn-Fe3O4@SiO2用于催化大豆卵磷脂（SLs）与短碳链脂肪酸（丙酸和丁酸）间的酸解反应来制备新型短碳链结构磷脂（SCSPLs）乳化剂，并对SCSPLs进行性能测定。结果表明，核壳结构Zn-Fe3O4@SiO2磁性微球负载了大量的活性Zn组分，因而可高效催化制备SCSPLs；在m(SLs)∶m(C3:0)∶m(C4:0)=1∶4∶4、催化剂用量为原料总质量的5%、反应温度为50 ℃、反应时间为5 h的条件下，SCSPLs的短碳链脂肪酸接入率可高达78.15%±1.08%（丙酸和丁酸的接入率分别为35.43%±0.62%和42.72%±0.55%），且Zn-Fe3O4@SiO2可通过外加磁场进行简单分离及循环5次而无明显失活；与SLs原料相比，SCSPLs的乳化性、分散性和氧化稳定性等均得到极大提高。     

二氧化硅-磺酸催化制备生物柴油的研究

通过溶胶-凝胶法制备二氧化硅,进而与氯磺酸反应制得二氧化硅-磺酸(SiO2-SO3H)固体酸催化剂,用于大豆油与乙醇的酯交换反应制备生物柴油,考察了催化剂的处理温度、乙醇与大豆油的摩尔比、催化剂用量、原料油油酸含量和反应时间的影响.结果表明,二氧化硅-磺酸(SiO2-SO3H)具有较高的酯交换反应催化活性.制备生物柴油的最佳条件如下:催化剂处理温度为120℃、醇油摩尔比为6∶1、催化剂质量分数为5.0%(以大豆油计)、正庚烷的质量分数(以大豆油计)为30.0%、反应时间为6.0 h,此时生物柴油产率可达97.84%.与固体碱催化剂相比,固体酸催化剂对原料的酸度有更强的适应性.     

锆基MOFs的合成和表征及催化制备生物柴油

采用不同有机配体（对苯二甲酸，2-硝基对苯二甲酸、2-氨基对苯二甲酸、2-羟基对苯二甲酸），利用剂热合成法合成锆基MOFs结构UiO-66及其衍生物，添加不同的调节剂（甲酸、乙酸、苯甲酸和盐酸）调节锆基MOFs结构。采用XRD、SEM和FT-IR等对锆基MOFs材料进行表征，研究不同的调节剂和添加量对锆基MOFs形貌特征和结构性质的影响。研究发现调节剂的不同对锆基MOFs结构形成产生不同影响，盐酸和乙酸混合调节剂能显著提高UiO-66的结晶度，当n(调节剂)∶n(ZrCl4)=30∶1时，苯甲酸调节剂可以获得尺寸为500 nm结构规整的UiO-66八面体晶体，甲酸调节剂将UiO-66的比表面积由1173.3 m2/g提高到1973.8 m2/g。选择3种锆基MOFs作为酯化反应催化剂，UiO-66-NH2催化活性较好，其游离脂肪酸转化率为50.7%，用KOH催化酯化油反应得到的生物柴油产率为51.6%，脂肪酸甲酯含量达99%以上。     

对甲苯磺酸季铵盐离子液体催化酯交换反应制备生物柴油

合成了4种不同阳离子的-SO3H功能化对甲苯磺酸季铵盐离子液体,并用FT-IR和NMR表征结构,结果表明,合成的离子液体符合其理论结构特征。热重分析实验表明离子液体的分解温度都在200℃以上,可以作为合成生物柴油的催化剂;采用吡啶红外探针法测定其酸性大小,实验结果表明其酸性受阳离子烷基侧链影响,烷基侧链越短或越少,酸性越强,但相差不大。以它们为催化剂进行了三油酸甘油酯酯交换反应制备生物柴油的研究,实验表明,这些-SO3H功能化对甲苯磺酸季铵盐离子液体的催化活性都较高,油酸甲酯的产率与离子液体的酸性顺序一致,正-丙基磺酸-三乙基对甲苯磺酸铵的催化活性最高。考察了正-丙基磺酸-三乙基对甲苯磺酸铵离子液体用量、醇油摩尔比、反应时间、反应温度对生物柴油产率的影响规律。实验结果表明,在甲醇、油脂和离子液体的摩尔比为12:1:0.167,反应温度130℃下反应4 h,油酸甲酯的产率可达到92.16%;将反应后离子液体相中的甲醇蒸出,再用乙酸乙酯将其中的甘油萃取出来,剩余的离子液体直接用于下次的酯交换反应,油酸甲酯的产率无明显降低,表明离子液体的稳定性好,回收的离子液体可循环使用。     

硅酸钠为硅源的介孔分子筛SBA-15-SO3H的研究

在强酸性和水热条件下以硅酸钠（Na₂SiO₃·9H₂O）为硅源合成表面含磺酸基的介孔分子筛催化剂SBA-15-SO₃H。XRD结果表明，该分子筛具有规则的六方立柱形介孔结构。SBA-15-SO3H用于叔丁醇和乙醇合成乙基叔丁基醚（ETBE）的醚化反应研究，分别考察了反应温度、原料配比和反应时间等因素对醚化反应的影响。最佳操作条件为：温度120 ℃，n(乙醇)∶n(叔丁醇)=2∶1，反应时间5 h，m(催化剂) ∶m(原料)=1∶10。在此条件下，叔丁醇的转化率为62.83%。     

UiO-66/GO纳米复合材料的合成及其增强的吸附性能

以ZrCl4, 和H2BDC和GO为原料,采用溶剂热法 合成了一种新型的纳米 复合材料UiO-66/氧化石墨烯（UiO-66/GO）。运用扫描电镜（SEM）和透射电镜（TEM）分析了复合材料的表面形貌和复合状态,观察到UiO-66均匀生长在GO片上形成一种2D负载结构。采用X-射线衍射（XRD）和红外光谱（FTIR）对复合材料的晶体成分结构和成分进行分析,发现GO的添加不影响UiO-66的晶型体结构。N2吸附-解吸等温线分析了纳米复合材料的比表面积和孔径分布,表明含有2% 质量比GO用量2%的UiO-66/GO复合材料 具有最高的比表面积 （738 m2/g）。UiO-66/GO-2 的协同效应 使其对刚果红（CR）的去除率远高于UiO-66和GO的,其最大吸附量为561.79 mg/g,分别是相同条件下UiO-66和GO对CR吸附量的2.8倍和7.1倍。     

介孔分子筛SBA-15-SO3H催化合成2-叔丁基对甲酚

以磺酸基介孔分子筛SBA-15-SO3H为催化剂,甲基叔丁基醚(MTBE)和对甲酚为原料合成了2-叔丁基对甲酚.考察了烷基化反应条件对反应转化率和选择性的影响以及催化剂的稳定性.结果表明,对甲酚转化率为87.4%,选择性为97.86%,SBA-15-SO3H分子筛是合成2-叔丁基对甲酚的理想催化剂.     

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.     

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.     

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。