With Bu4NBr as phase-transfer agent, the monovacant polyoxometalates α-Xn+W11O（12-n）-39（X=P, Si, B, Ga） reacted in acetonitrile with electrophilic C6H5P（S）Cl2 to yield hybrid organic-inorganic species [C6H5P（S...With Bu4NBr as phase-transfer agent, the monovacant polyoxometalates α-Xn+W11O（12-n）-39（X=P, Si, B, Ga） reacted in acetonitrile with electrophilic C6H5P（S）Cl2 to yield hybrid organic-inorganic species [C6H5P（S）]2XW11O（8-n）-39 in satisfactory yield, which have been characterized by elemental analyses, IR and 31P, 183W NMR. The formulation of all tetrabutylammonium salts of [C6H5P（S）]2·XW11（8-n）-O39 are in agreement with the results of elemental analyses, the hybrid anion consists of an α-Xn+W11O（12-n）-39 framework on which are grafted two C6H5P（S） groups through P\O\W bridges. The spectroscopic data show that the [PhP（S）]2XW11O（8-n）-39 compounds possess true Cs symmetry in acetonitrile and remain unsaturated.展开更多
以‘紫罗兰’紫薯为原料,研究同步提取紫薯花青素以及制备紫薯淀粉、纤维素和紫薯蛋白的工艺及参数。紫薯与酸乙醇(p H 2)混合破碎、过滤、沉淀分离淀粉;将滤渣和分离淀粉后上清液混合,用微波辅助法提取花青素并优化提取条件;花青素提...以‘紫罗兰’紫薯为原料,研究同步提取紫薯花青素以及制备紫薯淀粉、纤维素和紫薯蛋白的工艺及参数。紫薯与酸乙醇(p H 2)混合破碎、过滤、沉淀分离淀粉;将滤渣和分离淀粉后上清液混合,用微波辅助法提取花青素并优化提取条件;花青素提取液沉淀分离紫薯蛋白;提取花青素的滤渣制备紫薯纤维素。结果表明:微波辅助提取紫薯中花青素的最佳工艺条件为微波时间4 min、微波温度52℃、料液比1∶22.40(g/m L)、乙醇体积分数62%(p H 2),在此条件下紫薯花青素的提取率(93.64±0.69)%、粗提物中花青素含量(9.58±0.20)mg/g。制备的紫薯淀粉质量分数(95.77±0.41)%、得率(占总淀粉质量分数)(73.06±1.03)%;滤渣粉中纤维素含量(117.11±2.69) mg/g;制备的紫薯蛋白中蛋白质含量(524.78±24.84) mg/g。该制备方法能够提高紫薯的利用率,降低生产成本。展开更多
The relaxivities of two gadolinium heteropoly complexes β K 17 [(GdO) 3(SiW 9O 34 ) 2]·20H 2O and K 13 [Gd(GeW 11 O 39 ) 2]·20H 2O in aqueous solution have been measured. Their relaxivities are 16.27 and 16...The relaxivities of two gadolinium heteropoly complexes β K 17 [(GdO) 3(SiW 9O 34 ) 2]·20H 2O and K 13 [Gd(GeW 11 O 39 ) 2]·20H 2O in aqueous solution have been measured. Their relaxivities are 16.27 and 16.41 mmol -1 ·s -1 ·L, respectively. The results indicate that the two gadolinium heteropoly complexes may be potential contrast agents for MRI. [WT5HZ]展开更多
文摘With Bu4NBr as phase-transfer agent, the monovacant polyoxometalates α-Xn+W11O（12-n）-39（X=P, Si, B, Ga） reacted in acetonitrile with electrophilic C6H5P（S）Cl2 to yield hybrid organic-inorganic species [C6H5P（S）]2XW11O（8-n）-39 in satisfactory yield, which have been characterized by elemental analyses, IR and 31P, 183W NMR. The formulation of all tetrabutylammonium salts of [C6H5P（S）]2·XW11（8-n）-O39 are in agreement with the results of elemental analyses, the hybrid anion consists of an α-Xn+W11O（12-n）-39 framework on which are grafted two C6H5P（S） groups through P\O\W bridges. The spectroscopic data show that the [PhP（S）]2XW11O（8-n）-39 compounds possess true Cs symmetry in acetonitrile and remain unsaturated.
文摘以‘紫罗兰’紫薯为原料,研究同步提取紫薯花青素以及制备紫薯淀粉、纤维素和紫薯蛋白的工艺及参数。紫薯与酸乙醇(p H 2)混合破碎、过滤、沉淀分离淀粉;将滤渣和分离淀粉后上清液混合,用微波辅助法提取花青素并优化提取条件;花青素提取液沉淀分离紫薯蛋白;提取花青素的滤渣制备紫薯纤维素。结果表明:微波辅助提取紫薯中花青素的最佳工艺条件为微波时间4 min、微波温度52℃、料液比1∶22.40(g/m L)、乙醇体积分数62%(p H 2),在此条件下紫薯花青素的提取率(93.64±0.69)%、粗提物中花青素含量(9.58±0.20)mg/g。制备的紫薯淀粉质量分数(95.77±0.41)%、得率(占总淀粉质量分数)(73.06±1.03)%;滤渣粉中纤维素含量(117.11±2.69) mg/g;制备的紫薯蛋白中蛋白质含量(524.78±24.84) mg/g。该制备方法能够提高紫薯的利用率,降低生产成本。
文摘The relaxivities of two gadolinium heteropoly complexes β K 17 [(GdO) 3(SiW 9O 34 ) 2]·20H 2O and K 13 [Gd(GeW 11 O 39 ) 2]·20H 2O in aqueous solution have been measured. Their relaxivities are 16.27 and 16.41 mmol -1 ·s -1 ·L, respectively. The results indicate that the two gadolinium heteropoly complexes may be potential contrast agents for MRI. [WT5HZ]
