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磷酸吡哆醛是一种水溶性维生素,对人体内氨基酸反应有着促进作用,可作为治疗多种疾病的药物在医药方面的应用广泛,该物质合成时多以盐酸吡哆醇(VB6)为起始原料,经二氧化锰氧化反应、醛基保护、磷酸酯化和水解反应合成磷酸吡哆醛.本文利用吡哆醛生产过程中产生的含锰废水,采用分阶段调控耦合膜过滤技术处理,利用化学沉淀与膜过滤法相结... 相似文献
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引言壳聚糖是自然界中唯一含有氨基的碱性多糖,具有多样的生物活性、极好的生物相容性、生物可降解性以及无毒性等特性,是一种新兴的生物功能材料[1-3]。磷酸吡哆醛是维生素B6参与多种代谢反应的一种活性形式。磷酸吡哆醛作为一种辅酶参与所有转氨基反应及一些氨基酸的脱羧及脱氢反应。研究表明,磷酸吡哆醛不但可以用于预防治疗高血压、心血管疾病及糖尿病等,还可用于治疗迟发性运动障碍和治疗难治性儿童期癫痫[4-5]。王涛等[6]以壳聚糖微球为载体,然后固定磷酸吡哆醛等制备得到了低密度脂蛋白亲和吸附剂,用于去除高脂血症患 相似文献
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通过将醛缩酶(ALD)、D-丝氨酸脱水酶(SDH)和酪氨酸酚裂解酶(TPL)三酶偶联,催化甘氨酸、甲醛和苯酚合成L-酪氨酸(L-Tyr)。并以L-Tyr的质量浓度为指标对转化工艺进行了考察。结果表明:三酶偶联最佳反应条件为pH=8.5、温度35℃、乙酸铵质量分数6 g/L、磷酸吡哆醛(PLP)质量浓度0.1 g/L、3种酶细胞配比m(ALD)∶m(SDH)∶m(TPL)=6∶3∶5。当甘氨酸加量为50 g/L,利用上述工艺进行10000 L放大,反应11 h,L-Tyr质量浓度可达117 g/L,苯酚转化率为97%,转化体系放大后苯酚转化率提高4%,收率为85%。 相似文献
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《精细化工原料及中间体》2020,(5)
正本发明提供一种三磷酸腺苷(ATP)前体脂质体及其制备方法和应用。该方法按如下步骤进行:a.取三磷酸腺苷加入磷酸盐缓冲液溶解成三磷酸腺苷溶液,备用;b.取脂质体骨架材料与稳定剂加热熔融或用有机溶剂溶解成脂质溶液,备用;c.先将b步骤的脂质溶液与a步骤的三磷酸腺苷溶液混匀乳化后,于恒温水浴中减压旋转蒸发后制得液态三磷酸腺苷前体脂质体,然后加入冻干保护剂,经冷冻干燥或喷 相似文献
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采用静电纺丝法制备银修饰二氧化钛纳米纤维,通过XRD、TEM及UV-Vis等分析其基本物性,且在UV光与泛光波照射下探讨其对亚甲基蓝溶液的光降解效果。物性分析显示银修饰二氧化钛纳米纤维呈锐钛矿与金红石并存的多晶结构,且其在400~800 nm的吸光度峰值增强约50%,表明经银修饰后二氧化钛纤维的光吸收范围大大扩展。光降解分析显示经UV照射120 min后银修饰二氧化钛纳米纤维可将MB溶液的吸光度峰值降至0,经泛光波照射120 min后亦可将MB溶液的吸光度峰值降至0.1以下,说明经银修饰后二氧化钛纤维对MB具有较好的UV与泛光波光降解效能。 相似文献
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虫草素具有多种生物活性,通过与新型药物载体脂质体结合,可解决其临床中的脱氨基作用。2'-脱氧腺苷是虫草素的结构类似物,易制备,具有和虫草素相同的紫外最大吸收波长(259nm),是一种优良的虫草素替代品,研究2'-脱氧腺苷脂质体可为虫草素脂质体的研究提供重要的参考。本文采用逆相蒸发法制得球形、粒径170~350nm、包封率为45%、稳定性良好的2'-脱氧腺苷脂质体。为虫草素脂质体研究提供基础数据。 相似文献
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Tailoring activated carbons for enhanced removal of natural organic matter from natural waters 总被引:6,自引:0,他引:6
Several pathways have been employed to systematically modify two granular activated carbons (GACs), F400 (coal-based) and Macro (wood-based), for examining adsorption of dissolved natural organic matter (DOM) from natural waters. A total of 24 activated carbons with different physical and chemical characteristics was produced. The impact of carbon treatment on the DOM adsorption was examined by conducting isotherm experiments at a neutral pH using the modified carbons and a DOM isolated from the influent to Myrtle Beach drinking water treatment plant in South Carolina (USA). Adsorption of the DOM by two activated carbon fibers, with relatively uniform pore size distributions, showed that only pores with widths larger than 1 nm were accessible to the DOM macromolecules. Increases in the carbon supermicropore and mesopore volume (i.e., >1 nm) increased the DOM uptake, if the surface chemistry was favorable. The isotherms normalized on a surface area basis showed the significance of carbon surface chemistry on the DOM uptake. At neutral pH, adsorption of negatively charged DOM molecules was favored by basic and positively charged surfaces, while the DOM uptake was minimized when the surface had acidic characteristics. High temperature ammonia treatment of oxidized carbons considerably enhanced the DOM uptake, mainly due to the increase in accessible surface area and surface basicity. Iron-impregnated carbons indicated an enhanced affinity of iron-laden carbon surface toward the DOM species, if the surface was not negatively charged. 相似文献
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The transport of positively charged redox active species through spiropyran-modified nanopores in silica colloidal films was
controlled using light. The silica colloidal films were comprised of 18 layers of face centered cubic (fcc)-packed 170 nm
silica spheres. The surface of the films was first modified with amines, which were then used to attach the spiropyran moiety
to the surface. The limiting current of a positively charged redox active species through the spiropyran-modified nanopore
decreased after irradiation with UV light at pH 6.6. When the silica colloidal film was subsequently irradiated with visible
light the initial limiting current was restored. 相似文献
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利用醋酸锶与四苯基卟啉反应,合成了四苯基卟啉锶配合物。利用元素分析、红外、核磁共振等对该配合物进行了结构表征。采用紫外-可见吸收光谱、荧光光谱和循环伏安法研究了该配合物的光电性能。四苯基卟啉锶配合物紫外-可见吸收光谱有一个强的吸收峰和一个次强的吸收峰,分别为428、457 nm。荧光光谱有一个强的发射峰和一个弱的发射峰,分别为610、676 nm。循环伏安法测得其氧化峰电位为1.558 V和1.051 V。与四苯基卟啉相比,四苯基卟啉锶紫外吸收发生红移,而荧光发射发生蓝移。 相似文献
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一种适用于193nm光刻胶的硫鎓盐光产酸剂的制备与性质 总被引:5,自引:4,他引:5
制备了一种阳离子含有萘基,阴离子分别为对-甲苯磺酸、甲磺酸及三氟甲磺酸的硫鎓盐.它们有高的热解温度和在常用有机溶剂中较好的溶解性.测定了此类光产酸剂在水溶液及聚乙二醇固体膜层中的紫外吸收特性.结果表明,阴离子不合苯基时,在193nm处有很好的透明性.考察了其在低压汞灯照射下的光解性质,在254nm附近的吸收峰随光解进行迅速减弱.此类光产酸剂适用于氟化氩激光(193nm)等的化学增幅型光致抗蚀剂. 相似文献