用直接观察法、酒石酸亚铁法和铬黑 T 祛对绿茶茶汤组分与23种金属离子的络合性能进行了研究,结果表明,有22种金属离子可与茶汤组分发生络合或还原络合反应,其中有10种金属离子参与了茶多酚的络合。钙离子可与茶汤组分生成低溶解度的络...用直接观察法、酒石酸亚铁法和铬黑 T 祛对绿茶茶汤组分与23种金属离子的络合性能进行了研究,结果表明,有22种金属离子可与茶汤组分发生络合或还原络合反应,其中有10种金属离子参与了茶多酚的络合。钙离子可与茶汤组分生成低溶解度的络合物,其溶解度及稳定性可随反应溶液 pH 升高而下降。钙络合沉淀中的主要茶汤组分是茶多酚,其中以酯型儿茶素含量最高。展开更多
In order to solve the hardening problem of complex calcium lubricating grease, the water absorption test of several calcium salts was carried out, and it was found that calcium 12-hydroxystearate did not absorb water,...In order to solve the hardening problem of complex calcium lubricating grease, the water absorption test of several calcium salts was carried out, and it was found that calcium 12-hydroxystearate did not absorb water, and calcium acetate, calcium phosphate and calcium borate had different degrees of water absorption. Calcium acetate has the highest water absorption rate, while calcium phosphate and calcium borate show comparable water absorption rates. Upon using the molecular simulation technology, it is found that in the complex calcium grease system, calcium phosphate and calcium borate tend to combine with water, which inhibits the water absorption of calcium acetate and alleviate the hardening problem.展开更多
This study investigated the effect of a chitosan oligosaccharide-Ca complex (COS-Ca) on the depuration of cadmium (Cd) from Chlamys ferrari. After exposure to 0.5 mg L-1 CdCl2 for 3 or 7 d, the scallops were treated b...This study investigated the effect of a chitosan oligosaccharide-Ca complex (COS-Ca) on the depuration of cadmium (Cd) from Chlamys ferrari. After exposure to 0.5 mg L-1 CdCl2 for 3 or 7 d, the scallops were treated by COS-Ca prior to determina-tion of Cd, calcium (Ca) and zinc (Zn) contents, Cd distribution in organs, malondialdehyde (MDA) content and antioxidant variables. Results showed that COS-Ca reduced Cd content in the viscera of the scallops, with highest Cd depuration rate (47%) observed on day 3. The COS-Ca concentration substantially affected Cd depuration, and the exposure to 8.75 mg L-1 COS-Ca led to significantly higher Cd depuration rate compared with those of lower COS-Ca concentrations (1.75, 3.5, 5.25, and 7.00 mg L-1). Distribution analysis of Cd in scallop organs indicated that COS-Ca significantly reduced Cd content in the kidney throughout the 5-d experiment, as well as in the gill during the early stage of Cd depuration. In addition, COS-Ca treatment decreased glutathione peroxidase (GSH-Px) activity and MDA content while increasing superoxide dismutase (SOD) and catalase (CAT) activities on different days. Our work suggested COS-Ca complex treatment as an effective method for acceleration of Cd depuration from Cd-contaminated bivalves.展开更多
ackground Development of vulnerable lesions is not limited to the target lesions, but a pan-coronary process. Such lesions are identified by positive remodeling （intravascular ultrasound （IVUS） and complex lesions ...ackground Development of vulnerable lesions is not limited to the target lesions, but a pan-coronary process. Such lesions are identified by positive remodeling （intravascular ultrasound （IVUS） and complex lesions （angiography））. The prevalence of lesions with vulnerable characteristics in patients with stable angina was not well known. The purpose of the present study was to evaluate the relationship between coronary artery remodeling and incidence of angiographic complex lesions and its calcification in stable angina patients.Methods One hundred and sixty-one stable angina patients （95 males, aged （68±11） years） with 161 de novo target lesions were studied using pre-interventional IVUS. Remodeling index was defined as the lesion divided by reference vessel area; positive remodeling was defined as remodeling index 〉1.05. Besides the 161 target lesions, there were 613 angiographic lesions with 〉30% diameter stenoses, classified as complex or smooth. Multiple complexes were defined as more than one complex lesion in one patient. Stenoses of at least 70% were described as tight. Calcium arc area was used as a new method to quantify coronary calcification.Results Fifty-six patients had positive remodeling target lesion, while 105 did not. The overall number of lesions with a diameter stenoses 〉30% was similar in patients with or without positive remodeling, and the frequency of angiographically complex lesions was higher in positive remodeling patients, especially at non-target site. Calcium arc area was smaller in patients with positive remodeling.Conclusions Positive remodeling on intravascular ultrasound was associated with more complex lesions angiographic findings, especially at non target site. Positive remodeling was found less calcified in patients with stable angina.展开更多
The novel alkaline metal complex Ca（BPDCH）2 （1, BPDCH2 = 2,2＇-bipyri- dine-5,5＇-dicarboxylic acid） has been synthesized by the hydrothermal reaction of Ca（NO3）2·4H2O with 2,2＇-bipyridine-5,5＇-dicarboxyl...The novel alkaline metal complex Ca（BPDCH）2 （1, BPDCH2 = 2,2＇-bipyri- dine-5,5＇-dicarboxylic acid） has been synthesized by the hydrothermal reaction of Ca（NO3）2·4H2O with 2,2＇-bipyridine-5,5＇-dicarboxylic acid. The molecular and crystal structures of complex 1 have firstly been characterized by FTIR, elemental analysis, and X-ray single-crystal diffraction. The 3D MOF structure of complex 1 was interpreted by the versatile binding modes-the intermolecular hydrogen bonds and π-π stacking interactions of 2,2＇-bipyridine-5,5＇-dicarboxylic acid ligand. The analysis results show complex 1 belongs to a coordination polymer with 3D MOF structure. The results of thermogravimetric analysis and solubility demonstrate complex 1 is a thermostable compound and does not dissolve in water and traditional organic solvents.展开更多
文摘用直接观察法、酒石酸亚铁法和铬黑 T 祛对绿茶茶汤组分与23种金属离子的络合性能进行了研究,结果表明,有22种金属离子可与茶汤组分发生络合或还原络合反应,其中有10种金属离子参与了茶多酚的络合。钙离子可与茶汤组分生成低溶解度的络合物,其溶解度及稳定性可随反应溶液 pH 升高而下降。钙络合沉淀中的主要茶汤组分是茶多酚,其中以酯型儿茶素含量最高。
文摘In order to solve the hardening problem of complex calcium lubricating grease, the water absorption test of several calcium salts was carried out, and it was found that calcium 12-hydroxystearate did not absorb water, and calcium acetate, calcium phosphate and calcium borate had different degrees of water absorption. Calcium acetate has the highest water absorption rate, while calcium phosphate and calcium borate show comparable water absorption rates. Upon using the molecular simulation technology, it is found that in the complex calcium grease system, calcium phosphate and calcium borate tend to combine with water, which inhibits the water absorption of calcium acetate and alleviate the hardening problem.
基金supported by grants of the National Key Technology Research and Development Program in the 11th Five-Year Plan of China (2008BAD94B\09)the National Natural Science Foundation of China (Grant No. 30972289)
文摘This study investigated the effect of a chitosan oligosaccharide-Ca complex (COS-Ca) on the depuration of cadmium (Cd) from Chlamys ferrari. After exposure to 0.5 mg L-1 CdCl2 for 3 or 7 d, the scallops were treated by COS-Ca prior to determina-tion of Cd, calcium (Ca) and zinc (Zn) contents, Cd distribution in organs, malondialdehyde (MDA) content and antioxidant variables. Results showed that COS-Ca reduced Cd content in the viscera of the scallops, with highest Cd depuration rate (47%) observed on day 3. The COS-Ca concentration substantially affected Cd depuration, and the exposure to 8.75 mg L-1 COS-Ca led to significantly higher Cd depuration rate compared with those of lower COS-Ca concentrations (1.75, 3.5, 5.25, and 7.00 mg L-1). Distribution analysis of Cd in scallop organs indicated that COS-Ca significantly reduced Cd content in the kidney throughout the 5-d experiment, as well as in the gill during the early stage of Cd depuration. In addition, COS-Ca treatment decreased glutathione peroxidase (GSH-Px) activity and MDA content while increasing superoxide dismutase (SOD) and catalase (CAT) activities on different days. Our work suggested COS-Ca complex treatment as an effective method for acceleration of Cd depuration from Cd-contaminated bivalves.
文摘ackground Development of vulnerable lesions is not limited to the target lesions, but a pan-coronary process. Such lesions are identified by positive remodeling （intravascular ultrasound （IVUS） and complex lesions （angiography））. The prevalence of lesions with vulnerable characteristics in patients with stable angina was not well known. The purpose of the present study was to evaluate the relationship between coronary artery remodeling and incidence of angiographic complex lesions and its calcification in stable angina patients.Methods One hundred and sixty-one stable angina patients （95 males, aged （68±11） years） with 161 de novo target lesions were studied using pre-interventional IVUS. Remodeling index was defined as the lesion divided by reference vessel area; positive remodeling was defined as remodeling index 〉1.05. Besides the 161 target lesions, there were 613 angiographic lesions with 〉30% diameter stenoses, classified as complex or smooth. Multiple complexes were defined as more than one complex lesion in one patient. Stenoses of at least 70% were described as tight. Calcium arc area was used as a new method to quantify coronary calcification.Results Fifty-six patients had positive remodeling target lesion, while 105 did not. The overall number of lesions with a diameter stenoses 〉30% was similar in patients with or without positive remodeling, and the frequency of angiographically complex lesions was higher in positive remodeling patients, especially at non-target site. Calcium arc area was smaller in patients with positive remodeling.Conclusions Positive remodeling on intravascular ultrasound was associated with more complex lesions angiographic findings, especially at non target site. Positive remodeling was found less calcified in patients with stable angina.
基金Supported by the National Natural Science Foundation of China(NSFC 21266019,NSFC 21062011)the Natural Science Fundation of Inner Mongolia(20080404MS020)Program for New Century Excellent Talents in University(NCET-08-858)
文摘The novel alkaline metal complex Ca（BPDCH）2 （1, BPDCH2 = 2,2＇-bipyri- dine-5,5＇-dicarboxylic acid） has been synthesized by the hydrothermal reaction of Ca（NO3）2·4H2O with 2,2＇-bipyridine-5,5＇-dicarboxylic acid. The molecular and crystal structures of complex 1 have firstly been characterized by FTIR, elemental analysis, and X-ray single-crystal diffraction. The 3D MOF structure of complex 1 was interpreted by the versatile binding modes-the intermolecular hydrogen bonds and π-π stacking interactions of 2,2＇-bipyridine-5,5＇-dicarboxylic acid ligand. The analysis results show complex 1 belongs to a coordination polymer with 3D MOF structure. The results of thermogravimetric analysis and solubility demonstrate complex 1 is a thermostable compound and does not dissolve in water and traditional organic solvents.
