Synthesis and characterization of the copolymers （PAG） of α-methyl styrene （AMS） and glycidyl methacrylate （GMA） are presented. The copolymers of PAG were characterized by gel permeation chromatography （GPC）,...Synthesis and characterization of the copolymers （PAG） of α-methyl styrene （AMS） and glycidyl methacrylate （GMA） are presented. The copolymers of PAG were characterized by gel permeation chromatography （GPC）, Fourier transform infrared spectroscopy （FTIR）, nuclear magnetic resonance （^1H-NMR） and thermogravimetery （TG）. Based on the copolymer compositions determined by ^1H-NMR, the reactivity ratios of AMS and GMA were found to be 0.105 ± 0.012 and 0.883 ± 0.046 respectively by Kelen-Tudos method. TG revealed that thermal stability of the copolymers decreased with increasing the AMS content in the copolymers, which indicated that the degradation was mainly caused by the chain scission of AMS-containing structures. Under heating, the copolymers depolymerize at their weak bonds and form chain radicals, which could further initiate other chemical reactions.展开更多
目的研究在没有对照品的情况下鉴定检材中1-(4-氟苯基)-2-(N-吡咯烷基)-1-戊酮[1-(4-fluorophenyl)-2-(1-pyrrolidinyl)pentan-1-one,4-F-α-PVP]类似物1-(4-氟-3甲基苯基)-2-(N-吡咯烷基)-1-戊酮[1-(4-fluoro-3-methyl phenyl)-2-(1-py...目的研究在没有对照品的情况下鉴定检材中1-(4-氟苯基)-2-(N-吡咯烷基)-1-戊酮[1-(4-fluorophenyl)-2-(1-pyrrolidinyl)pentan-1-one,4-F-α-PVP]类似物1-(4-氟-3甲基苯基)-2-(N-吡咯烷基)-1-戊酮[1-(4-fluoro-3-methyl phenyl)-2-(1-pyrrolidinyl)pentan-1-one,4-F-3-Methyl-α-PVP]盐酸盐的方法。方法综合利用直接进样电子电离-质谱(electron ionization-mass spectrometry,EI-MS)、GCMS、电喷雾离子化-高分辨质谱(electrospray ionization-high resolution mass spectrometry,ESI-HRMS)、超高效液相色谱-高分辨串联质谱(ultra-high performance liquid chromatography-high resolution tandem mass spectrometry,UPLC-HRMS/MS)、核磁共振(nuclear magnetic resonance,NMR)、离子色谱和傅里叶变换红外光谱法(Fourier transform infrared spectroscopy,FTIR),实现对检材中未知化合物的结构解析与表征,并对该化合物在EI-MS和UPLC-HRMS/MS两种质谱分析方式下生成碎片离子的裂解机制进行推导。结果通过对检材中化合物的直接进样EI-MS、GC-MS、ESI-HRMS和UPLC-HRMS/MS分析,推断出未知化合物为4-F-α-PVP的结构类似物,可能苯环中多了1个甲基。根据核磁共振氢谱(1H-nuclear magnetic reso⁃nance,1 H-NMR)、核磁共振碳谱(13C-nuclear magnetic resonance,13C-NMR)等分析结果,进一步证明了甲基的位置在苯环的3-位。由于1H-NMR分析中实际氢的个数比4-F-3-Methyl-α-PVP中性分子多1个,推断该化合物以盐形式存在。离子色谱法分析结果表明该化合物含氯离子(含量11.14%~11.16%),结合FTIR对主要官能团信息的结构分析,最终确定该未知化合物为4-F-3-Methyl-α-PVP盐酸盐。结论建立了综合利用EI-MS、GC-MS、ESI-HRMS、UPLC-HRMS/MS、NMR、离子色谱和FTIR鉴定检材中4-F-3-Methyl-α-PVP盐酸盐的方法,将有助于法庭科学实验室在案件中鉴定该物质或其他具有类似结构的化合物。展开更多
α-{ 3-[2-hydroxy-3-（N-methyl-N-hydroxyethylamino）propoxy]propyl }-α-butylpolydimethylsiloxanes III with various molecu- lar weights were prepared by epoxy addition of α-[3-（2,3-epoxy-propoxy）propyl]-α-butylpol...α-{ 3-[2-hydroxy-3-（N-methyl-N-hydroxyethylamino）propoxy]propyl }-α-butylpolydimethylsiloxanes III with various molecu- lar weights were prepared by epoxy addition of α-[3-（2,3-epoxy-propoxy）propyl]-α-butylpolydimethylsiloxanes Ⅱ and N- methylmonoethanolamine. At each step, the outcome compounds were characterized through FT-IR and NMR spectra, the results showed that each step was successfully carried out and objective products were achieved.展开更多
Persistent postsurgical pain is a serious issue in public health, which has received increased interest in recent years. Previous studies have reported that psychological factors promote the development of chronic pos...Persistent postsurgical pain is a serious issue in public health, which has received increased interest in recent years. Previous studies have reported that psychological factors promote the development of chronic postsurgical pain. However, it is unclear how chronification of postsurgical pain occurs. The α-amino-3-hydroxy-5-methyl-4-isoxazole-propionic acid receptor(AMPA) phosphorylation in the central nervous system plays a critical role in synaptic plasticity and contributes to central sensitization and chronic pain development. Here, we discuss the role of AMPA receptor regulation in stress-induced pain chronification after surgery.展开更多
This study was carried out in 2022 at the Itato agriculture community estate of fish hatchery in eastern Senegal with the aim of finding an alternative method to 17-α-methyl testosterone (MT) by using Garcinia kola ...This study was carried out in 2022 at the Itato agriculture community estate of fish hatchery in eastern Senegal with the aim of finding an alternative method to 17-α-methyl testosterone (MT) by using Garcinia kola “Bitter kola” powder to obtain Oreochromis niloticus male sex populations. 1800 fry of average size between 0.01 and 0.02 g were distributed in 12 aboveground tanks of 1 m3 each at a rate of 150 individuals/tank, following 6 duplicate treatments. The negative (B1 and B2) and positive (B3 and B4) control diets, to which between 0 and 60 mg/kg of 17alpha-methyl testosterone had been added respectively, were mixed with industrial feed containing 40% protein;the tank diets (B5 and B6), (B7 and B8), (B9 and B10) and (B11 and B12) contained 10 g, 20 g, 30 g and 40 g of Garcinia kola powder respectively for 1 kg of industrial feed con-taining 40% protein. These different treatments resulted in high proportions of males in the order of 97.03%;98.09% for the hormone and proportions of 94.03%;93.26% for 20 g of Garcinia kola extracts. In terms of weight growth, the best average weights for the hormone and Garcinia kola were 0.896 g and 0.980 g respectively. With regard to fish survival, the following results were recorded: 95.53% and 94.56% respectively for additions of 20 g and 30 g of Garcinia kola extracts to the feed supplied to the fish. On the other hand, a significant difference in the mortality rate of 35% and 5% respectively for the conventional hormone and 20 g of Garcinia kola extracts was observed. To conclude the study, it is recommended that further studies be carried out to determine the quality of the flesh, their life stages and the profile of the amino acids present in their proteins.展开更多
The modification of PAMAM( G =3 0) dendrimers was achieved by using aldehyde, benzyl chloride and trityl chloride as reaction agents, respectively. The complexes were synthesized simply by dropping TiCl 4 solution int...The modification of PAMAM( G =3 0) dendrimers was achieved by using aldehyde, benzyl chloride and trityl chloride as reaction agents, respectively. The complexes were synthesized simply by dropping TiCl 4 solution into the modified PAMAM dendrimers that were dissolved in certain solvent. The quantity of Ti contained in the complexes increased as the adding amount of TiCl 4 was increased. The polymerization of α methyl styrene catalyzed by the complexes was accomplished and it has shown that the complexes possessed catalytic function.展开更多
文摘Synthesis and characterization of the copolymers （PAG） of α-methyl styrene （AMS） and glycidyl methacrylate （GMA） are presented. The copolymers of PAG were characterized by gel permeation chromatography （GPC）, Fourier transform infrared spectroscopy （FTIR）, nuclear magnetic resonance （^1H-NMR） and thermogravimetery （TG）. Based on the copolymer compositions determined by ^1H-NMR, the reactivity ratios of AMS and GMA were found to be 0.105 ± 0.012 and 0.883 ± 0.046 respectively by Kelen-Tudos method. TG revealed that thermal stability of the copolymers decreased with increasing the AMS content in the copolymers, which indicated that the degradation was mainly caused by the chain scission of AMS-containing structures. Under heating, the copolymers depolymerize at their weak bonds and form chain radicals, which could further initiate other chemical reactions.
文摘目的研究在没有对照品的情况下鉴定检材中1-(4-氟苯基)-2-(N-吡咯烷基)-1-戊酮[1-(4-fluorophenyl)-2-(1-pyrrolidinyl)pentan-1-one,4-F-α-PVP]类似物1-(4-氟-3甲基苯基)-2-(N-吡咯烷基)-1-戊酮[1-(4-fluoro-3-methyl phenyl)-2-(1-pyrrolidinyl)pentan-1-one,4-F-3-Methyl-α-PVP]盐酸盐的方法。方法综合利用直接进样电子电离-质谱(electron ionization-mass spectrometry,EI-MS)、GCMS、电喷雾离子化-高分辨质谱(electrospray ionization-high resolution mass spectrometry,ESI-HRMS)、超高效液相色谱-高分辨串联质谱(ultra-high performance liquid chromatography-high resolution tandem mass spectrometry,UPLC-HRMS/MS)、核磁共振(nuclear magnetic resonance,NMR)、离子色谱和傅里叶变换红外光谱法(Fourier transform infrared spectroscopy,FTIR),实现对检材中未知化合物的结构解析与表征,并对该化合物在EI-MS和UPLC-HRMS/MS两种质谱分析方式下生成碎片离子的裂解机制进行推导。结果通过对检材中化合物的直接进样EI-MS、GC-MS、ESI-HRMS和UPLC-HRMS/MS分析,推断出未知化合物为4-F-α-PVP的结构类似物,可能苯环中多了1个甲基。根据核磁共振氢谱(1H-nuclear magnetic reso⁃nance,1 H-NMR)、核磁共振碳谱(13C-nuclear magnetic resonance,13C-NMR)等分析结果,进一步证明了甲基的位置在苯环的3-位。由于1H-NMR分析中实际氢的个数比4-F-3-Methyl-α-PVP中性分子多1个,推断该化合物以盐形式存在。离子色谱法分析结果表明该化合物含氯离子(含量11.14%~11.16%),结合FTIR对主要官能团信息的结构分析,最终确定该未知化合物为4-F-3-Methyl-α-PVP盐酸盐。结论建立了综合利用EI-MS、GC-MS、ESI-HRMS、UPLC-HRMS/MS、NMR、离子色谱和FTIR鉴定检材中4-F-3-Methyl-α-PVP盐酸盐的方法,将有助于法庭科学实验室在案件中鉴定该物质或其他具有类似结构的化合物。
基金the Natural Science Foundation of Shandong Province(No.Y2006B22).
文摘α-{ 3-[2-hydroxy-3-（N-methyl-N-hydroxyethylamino）propoxy]propyl }-α-butylpolydimethylsiloxanes III with various molecu- lar weights were prepared by epoxy addition of α-[3-（2,3-epoxy-propoxy）propyl]-α-butylpolydimethylsiloxanes Ⅱ and N- methylmonoethanolamine. At each step, the outcome compounds were characterized through FT-IR and NMR spectra, the results showed that each step was successfully carried out and objective products were achieved.
基金Supported by The National Institute of Dental and Craniofacial Research Grants,Nos.R01 DE022880 and K02 DE023551
文摘Persistent postsurgical pain is a serious issue in public health, which has received increased interest in recent years. Previous studies have reported that psychological factors promote the development of chronic postsurgical pain. However, it is unclear how chronification of postsurgical pain occurs. The α-amino-3-hydroxy-5-methyl-4-isoxazole-propionic acid receptor(AMPA) phosphorylation in the central nervous system plays a critical role in synaptic plasticity and contributes to central sensitization and chronic pain development. Here, we discuss the role of AMPA receptor regulation in stress-induced pain chronification after surgery.
文摘This study was carried out in 2022 at the Itato agriculture community estate of fish hatchery in eastern Senegal with the aim of finding an alternative method to 17-α-methyl testosterone (MT) by using Garcinia kola “Bitter kola” powder to obtain Oreochromis niloticus male sex populations. 1800 fry of average size between 0.01 and 0.02 g were distributed in 12 aboveground tanks of 1 m3 each at a rate of 150 individuals/tank, following 6 duplicate treatments. The negative (B1 and B2) and positive (B3 and B4) control diets, to which between 0 and 60 mg/kg of 17alpha-methyl testosterone had been added respectively, were mixed with industrial feed containing 40% protein;the tank diets (B5 and B6), (B7 and B8), (B9 and B10) and (B11 and B12) contained 10 g, 20 g, 30 g and 40 g of Garcinia kola powder respectively for 1 kg of industrial feed con-taining 40% protein. These different treatments resulted in high proportions of males in the order of 97.03%;98.09% for the hormone and proportions of 94.03%;93.26% for 20 g of Garcinia kola extracts. In terms of weight growth, the best average weights for the hormone and Garcinia kola were 0.896 g and 0.980 g respectively. With regard to fish survival, the following results were recorded: 95.53% and 94.56% respectively for additions of 20 g and 30 g of Garcinia kola extracts to the feed supplied to the fish. On the other hand, a significant difference in the mortality rate of 35% and 5% respectively for the conventional hormone and 20 g of Garcinia kola extracts was observed. To conclude the study, it is recommended that further studies be carried out to determine the quality of the flesh, their life stages and the profile of the amino acids present in their proteins.
文摘The modification of PAMAM( G =3 0) dendrimers was achieved by using aldehyde, benzyl chloride and trityl chloride as reaction agents, respectively. The complexes were synthesized simply by dropping TiCl 4 solution into the modified PAMAM dendrimers that were dissolved in certain solvent. The quantity of Ti contained in the complexes increased as the adding amount of TiCl 4 was increased. The polymerization of α methyl styrene catalyzed by the complexes was accomplished and it has shown that the complexes possessed catalytic function.
