We demonstrated a unique synthesis approach of graphene（GR）-wrapped AgPO/LaCOOH（APO/LCO）heterostructures by an in-situ wet chemical method. FESEM analysis reveals the formation of rhombic dodecahedrons of APO deco...We demonstrated a unique synthesis approach of graphene（GR）-wrapped AgPO/LaCOOH（APO/LCO）heterostructures by an in-situ wet chemical method. FESEM analysis reveals the formation of rhombic dodecahedrons of APO decorated with LCO and later wrapped with GR flakes. Optical studies shows two absorption edges corresponding to the band gap energies of APO（2.41 eV） and LCO（4.1 eV）. Considering the absorption edge of the heterostructures in the visible region, the photocatalytic activities of photocatalysts containing different APO/LCO mass ratios were evaluated by the degradation of MB. GR-decorated composite with 20% LCO（APO/LCO20/GR） exhibited the highest photocatalytic activity for MB degradation, with a rate constant, k of 0.541 min. The photocatalytic activity of APO/LCO20/GR more greatly enhanced than those of the individual constituents（APO, LCO, APO/LCO20）. The enhanced photocatalytic activity of the heterostructure can be attributed to the co-catalytic effect of LCO as well as intriguing physicochemical properties of GR. To understand the enhanced photocatalytic activity of the heterostructures the photocatalytic reaction mechanism is proposed in detail. The recyclability of the APO/LCO/GR composite photocatalyst is further evaluated by reusing the catalyst in replicate photocatalytic experiments which shows consistent photocatalytic activity thereby confirms the stability and reusability of heterostructure photocatalyst.展开更多
The electronic structure and chemical bonding of the title comp- lexes have been studied by an unrestricted INDO program made applicable for the lanthanoid compounds.The results indicated:(1)In coordinated bonds O-Ln ...The electronic structure and chemical bonding of the title comp- lexes have been studied by an unrestricted INDO program made applicable for the lanthanoid compounds.The results indicated:(1)In coordinated bonds O-Ln and N-Ln,5d orbitals of Ln have large contribution in all valence orbitals of Ln and 4f orbitals have very small contribution.(2)The covalent chara- cter and ionic character are almost equal in the chemical bond which is comparatively weak between phen,C_2H_5OH and Ln are mainly ionic with some covalent character.展开更多
目的了解西安市3~18儿童维生素D[25(OH)VitD,简称VitD]的营养状况及影响因素。方法选择2015年7月到2017年2月期间的寒、暑假在西安交通大学第一附属医院儿保科做健康体检的533例3~18岁西安市儿童为研究对象,采用酶联免疫吸附法(ELISA)...目的了解西安市3~18儿童维生素D[25(OH)VitD,简称VitD]的营养状况及影响因素。方法选择2015年7月到2017年2月期间的寒、暑假在西安交通大学第一附属医院儿保科做健康体检的533例3~18岁西安市儿童为研究对象,采用酶联免疫吸附法(ELISA)检测其血清VitD水平,并分析季节和性别的影响;进一步按照被研究儿童所处学校的性质,将其分为幼儿园组,小学组和中学组,比较三组儿童VitD的营养状况。结果儿童血清VitD水平为24.94±1.03ng/mL,VitD缺乏和不足的检出率分别为34.71%(185/533)和34.15%(182/533)。寒假与暑假儿童VitD水平(21.20±11.01ng/mL vs 27.71±8.68ng/mL,t=7.62,P<0.001)及不同VitD水平的检出率差异均有统计学意义(57.71%vs 17.64%,χ~2=93.13,P<0.001)。男童与女童VitD水平(25.06±10.67ng/mL vs 24.72±9.52ng/mL,t=0.38,P>0.05)及VitD缺乏检出率(35.03%vs 34.17%,χ~2=0.04,P>0.05)差异均无统计学意义。幼儿园组、小学组和中学组VitD水平分别为31.93±10.02ng/mL、22.33±8.34ng/mL和19.45±7.27ng/mL(各组间比较t值分别为10.56、10.49和2.19,均P<0.05),且三组儿童不同水平VitD的检出率差异存在统计学意义(χ~2=125.82,P<0.05)。结论西安市3~18岁儿童VitD缺乏率较高,尤其是中、小学阶段的儿童更为突出,医务人员应重视对该部分儿童VitD营养的保健指导。展开更多
Intestinal Ca2+ absorption is a crucial physiological process for maintaining bone mineralization and Ca2+ homeostasis. It occurs through the transcellular and paracellular pathways. The first route comprises 3steps: ...Intestinal Ca2+ absorption is a crucial physiological process for maintaining bone mineralization and Ca2+ homeostasis. It occurs through the transcellular and paracellular pathways. The first route comprises 3steps: the entrance of Ca2+ across the brush border membranes(BBM) of enterocytes through epithelial Ca2+ channels TRPV6, TRPV5, and Cav1.3; Ca2+ movement from the BBM to the basolateral membranes by binding proteins with high Ca2+ affinity(such as CB9k); and Ca2+ extrusion into the blood. Plasma membrane Ca2+ ATPase(PMCA1b) and sodium calcium exchanger(NCX1) are mainly involved in the exit of Ca2+ from enterocytes. A novel molecule, the 4.1R protein, seems to be a partner of PMCA1 b, since both molecules colocalize and interact. The paracellular pathway consists of Ca2+ transport through transmembrane proteins of tight junction structures, such as claudins 2, 12, and 15. There is evidence of crosstalk between the transcellular and paracellular pathways in intestinal Ca2+ transport. When intestinal oxidative stress is triggered, there is a decrease in the expression of several molecules of both pathways that inhibit intestinal Ca2+ absorption. Normalization of redox status in the intestine with drugs such as quercetin, ursodeoxycholic acid, or melatonin return intestinal Ca2+ transport to control values. Calcitriol [1,25(OH)2D3] is the major controlling hormone of intestinal Ca2+ transport. It increases the gene and protein expression of most of the molecules involved in both pathways. PTH, thyroid hormones, estrogens, p ro l a c t i n, g ro w t h h o r m o n e, a n d g l u c o c o r t i c o i d s apparently also regulate Ca2+ transport by direct action, indirect mechanism mediated by the increase of renal 1,25(OH)2D3 production, or both. Different physiological conditions, such as growth, pregnancy, lactation, and aging, adjust intestinal Ca2+ absorption according to Ca2+ demands. Better knowledge of the molecular details of intestinal Ca2+ absorption could lead to the development of nutritional and medical strategies for optimizing the efficiency of intestinal Ca2+ absorption and preventing osteoporosis and other pathologies related to Ca2+ metabolism.展开更多
基金Department of Electronics and Information Technology (Deit Y, New Delhi) for financial supportUGC-SAP, DST-FIST Department of Chemistry, Shivaji University Kolhapursupported by the Commercialization Promotion Agency for R&D Outcomes (COMPA) funded by the Ministry of Science, ICT and Future Planning (MISP) and NRF-2013R1A2A2A05005589
文摘We demonstrated a unique synthesis approach of graphene（GR）-wrapped AgPO/LaCOOH（APO/LCO）heterostructures by an in-situ wet chemical method. FESEM analysis reveals the formation of rhombic dodecahedrons of APO decorated with LCO and later wrapped with GR flakes. Optical studies shows two absorption edges corresponding to the band gap energies of APO（2.41 eV） and LCO（4.1 eV）. Considering the absorption edge of the heterostructures in the visible region, the photocatalytic activities of photocatalysts containing different APO/LCO mass ratios were evaluated by the degradation of MB. GR-decorated composite with 20% LCO（APO/LCO20/GR） exhibited the highest photocatalytic activity for MB degradation, with a rate constant, k of 0.541 min. The photocatalytic activity of APO/LCO20/GR more greatly enhanced than those of the individual constituents（APO, LCO, APO/LCO20）. The enhanced photocatalytic activity of the heterostructure can be attributed to the co-catalytic effect of LCO as well as intriguing physicochemical properties of GR. To understand the enhanced photocatalytic activity of the heterostructures the photocatalytic reaction mechanism is proposed in detail. The recyclability of the APO/LCO/GR composite photocatalyst is further evaluated by reusing the catalyst in replicate photocatalytic experiments which shows consistent photocatalytic activity thereby confirms the stability and reusability of heterostructure photocatalyst.
文摘The electronic structure and chemical bonding of the title comp- lexes have been studied by an unrestricted INDO program made applicable for the lanthanoid compounds.The results indicated:(1)In coordinated bonds O-Ln and N-Ln,5d orbitals of Ln have large contribution in all valence orbitals of Ln and 4f orbitals have very small contribution.(2)The covalent chara- cter and ionic character are almost equal in the chemical bond which is comparatively weak between phen,C_2H_5OH and Ln are mainly ionic with some covalent character.
文摘目的了解西安市3~18儿童维生素D[25(OH)VitD,简称VitD]的营养状况及影响因素。方法选择2015年7月到2017年2月期间的寒、暑假在西安交通大学第一附属医院儿保科做健康体检的533例3~18岁西安市儿童为研究对象,采用酶联免疫吸附法(ELISA)检测其血清VitD水平,并分析季节和性别的影响;进一步按照被研究儿童所处学校的性质,将其分为幼儿园组,小学组和中学组,比较三组儿童VitD的营养状况。结果儿童血清VitD水平为24.94±1.03ng/mL,VitD缺乏和不足的检出率分别为34.71%(185/533)和34.15%(182/533)。寒假与暑假儿童VitD水平(21.20±11.01ng/mL vs 27.71±8.68ng/mL,t=7.62,P<0.001)及不同VitD水平的检出率差异均有统计学意义(57.71%vs 17.64%,χ~2=93.13,P<0.001)。男童与女童VitD水平(25.06±10.67ng/mL vs 24.72±9.52ng/mL,t=0.38,P>0.05)及VitD缺乏检出率(35.03%vs 34.17%,χ~2=0.04,P>0.05)差异均无统计学意义。幼儿园组、小学组和中学组VitD水平分别为31.93±10.02ng/mL、22.33±8.34ng/mL和19.45±7.27ng/mL(各组间比较t值分别为10.56、10.49和2.19,均P<0.05),且三组儿童不同水平VitD的检出率差异存在统计学意义(χ~2=125.82,P<0.05)。结论西安市3~18岁儿童VitD缺乏率较高,尤其是中、小学阶段的儿童更为突出,医务人员应重视对该部分儿童VitD营养的保健指导。
文摘Intestinal Ca2+ absorption is a crucial physiological process for maintaining bone mineralization and Ca2+ homeostasis. It occurs through the transcellular and paracellular pathways. The first route comprises 3steps: the entrance of Ca2+ across the brush border membranes(BBM) of enterocytes through epithelial Ca2+ channels TRPV6, TRPV5, and Cav1.3; Ca2+ movement from the BBM to the basolateral membranes by binding proteins with high Ca2+ affinity(such as CB9k); and Ca2+ extrusion into the blood. Plasma membrane Ca2+ ATPase(PMCA1b) and sodium calcium exchanger(NCX1) are mainly involved in the exit of Ca2+ from enterocytes. A novel molecule, the 4.1R protein, seems to be a partner of PMCA1 b, since both molecules colocalize and interact. The paracellular pathway consists of Ca2+ transport through transmembrane proteins of tight junction structures, such as claudins 2, 12, and 15. There is evidence of crosstalk between the transcellular and paracellular pathways in intestinal Ca2+ transport. When intestinal oxidative stress is triggered, there is a decrease in the expression of several molecules of both pathways that inhibit intestinal Ca2+ absorption. Normalization of redox status in the intestine with drugs such as quercetin, ursodeoxycholic acid, or melatonin return intestinal Ca2+ transport to control values. Calcitriol [1,25(OH)2D3] is the major controlling hormone of intestinal Ca2+ transport. It increases the gene and protein expression of most of the molecules involved in both pathways. PTH, thyroid hormones, estrogens, p ro l a c t i n, g ro w t h h o r m o n e, a n d g l u c o c o r t i c o i d s apparently also regulate Ca2+ transport by direct action, indirect mechanism mediated by the increase of renal 1,25(OH)2D3 production, or both. Different physiological conditions, such as growth, pregnancy, lactation, and aging, adjust intestinal Ca2+ absorption according to Ca2+ demands. Better knowledge of the molecular details of intestinal Ca2+ absorption could lead to the development of nutritional and medical strategies for optimizing the efficiency of intestinal Ca2+ absorption and preventing osteoporosis and other pathologies related to Ca2+ metabolism.
