The nickel electroplating process was investigated by means of electrochemical noise(EN), cyclic voltammetry in conjunction with the scanning electron microscopy(SEM) technique. The results show that, in the experimen...The nickel electroplating process was investigated by means of electrochemical noise(EN), cyclic voltammetry in conjunction with the scanning electron microscopy(SEM) technique. The results show that, in the experimental conditions and with the increase of current density, the growth mechanism of nickel crystallites changes from 2-D to 3-D with the potential turning point of about -1.15 V, and the potential for the onset of diffusion control of the ensemble nickel electroplating process was about -1.4 V. In the case of activation-control, the two-dimensional (2-D) nucleation / growth process of nickel often results in the electrocrystallization EN features of only slowly small positive potential drift and the corresponding compact layer-by-layer deposit structure, and the maximum relative energy of the RP-EDP (re-plotted relative energy distribution plot), which is obtained from wavelet analysis, defined in the region with smaller scales. While under the diffusion-control, the three-dimensional (3-D) nucleation / growth process of nickel, often results in the electrocrystallization EN features of both the fast positive potential drift and subsequent remarkable negative potential drift and the corresponding dentritic/large conglomerate structure of nickel deposit, and the maximum relative energy of the RP-EDP defined in the region with larger scales. The electroplating time affects the nickel deposit structure mainly through its influence on the growth rate of crystallites and the Ni2+ ions diffusion process around each crystallite.展开更多
Pig pancreas ferritin（PPF） was purified by ultra-centrifugation, ion-exchange chromatography, and native gradient polyacrylamide gel electrophoresis（PAGENG）. Sodium dodecyl sulfate（SDS）-PAGE indicates that PPF c...Pig pancreas ferritin（PPF） was purified by ultra-centrifugation, ion-exchange chromatography, and native gradient polyacrylamide gel electrophoresis（PAGENG）. Sodium dodecyl sulfate（SDS）-PAGE indicates that PPF consists of two subunit types, namely, H（21000） and L（19000） subunits, and its core shows an average element composition of 1698 Fe3＋ and 179 phosphate molecules within the hollow shell, giving a 9.5：1 ratio of Fe3＋ to phosphate. An off line approach combining reversed-phase high-performance liquid chromatography（RP-HPLC） with matrix-assisted laser desorption ionization time of flight mass spectrometry（MALDI-TOF MS） made the decomposition of PPF shell into H and L subunits for the analysis of mass spectrometry（MS）, giving molecular weights of both H（21014.4） and L（18319.9） subunits. Both subunit types were further identified by an approach combining peptide mass fingerprint（PMF） with database search. A ratio of 1H to 2L subunits in PPF was determined by SDS-PAGE, RP-HPLC, and MALDI-TOF MS, respectively. It is well known that the non-covalent interaction of L-L or H-L subunits is stronger than that of H-H subunits in PPF, which may be further used to explain the unclear physiological function between H and L subunits in PPF.展开更多
针对室内环境基于RSSI定位不稳定问题,提出了以几何信息改进基于指纹库的KNN定位算法。根据室内几何布局建立了聚类指纹库,提出了表征点位几何特性的点散发性强度(geometric strength of sporadic,GSS)概念。利用最邻近样本点的GSS判别...针对室内环境基于RSSI定位不稳定问题,提出了以几何信息改进基于指纹库的KNN定位算法。根据室内几何布局建立了聚类指纹库,提出了表征点位几何特性的点散发性强度(geometric strength of sporadic,GSS)概念。利用最邻近样本点的GSS判别移动终端所在参考点RP控制网结构以动态选择KNN关键参数K,构建最佳多边形为约束准则自适应选取后K-1个邻近点,建立了基于几何聚类指纹库的约束加权KNN室内定位模型。结果表明,改进后定位模型可以更好地估计终端位置信息,其中几何聚类指纹库是改善定位准确性的关键,约束KNN能够有效地提高室内定位精度。展开更多
Sixteen indole derivatives have been computed at B3LYP/6-31 IG^＊＊ level using density functional theory （DFF）. Based on linear solvation energy theory, the structural parameters were employed to present correlatio...Sixteen indole derivatives have been computed at B3LYP/6-31 IG^＊＊ level using density functional theory （DFF）. Based on linear solvation energy theory, the structural parameters were employed to present correlation between the parameters of chromatograph capacity factor （CCF） and molecular structural parameters. As a result, the correlation equation of the reversed phased high performance liquid chromatograph capacity factor to the intercept lgk＇w and slope S of CCF were obtained, from which the correlation coefficients of lgk＇w to the structural parameters are r^2 = 0.9596 and q^2 = 0.9262. While the correlation coefficients of the parameter S r^2 q^2 with structures are = 0.9750 and = 0.9252. Moreover, the effect of water as solvent on the present two models was also considered using SCRF method, and the result shows that the predicting capacity of correlation equation of lgkw＇ increases, while that of the model for S decreases slightly. Both two correlation equations achieved in this work are more advantageous than those using theoretical descriptors from molecular connectivity indices.展开更多
A study has been carried out of evaluating lipophilicity of some 1 1, 2, 4 triazole compounds by RP HPTLC. An equation that reasonably correlates partition coefficients( c lg P ) with R M 0 values for 23 \{1 1,2,4 tri...A study has been carried out of evaluating lipophilicity of some 1 1, 2, 4 triazole compounds by RP HPTLC. An equation that reasonably correlates partition coefficients( c lg P ) with R M 0 values for 23 \{1 1,2,4 triazole\} compounds was derived and its predictive capability was tested with five 1 1,2,4 triazole compounds. It has been found that RP HPTLC can be extensively applied to determining lipophilicity of \{1 1,2,4 triazole\} compounds.展开更多
Dear Editor, Coxsackievirus A16 （CV A16） and enterovirus 71 （EV71） are currently the two primary causative agents of hand- foot-and-mouth disease （HFMD） （Solomon et al., 2010; Mao et al., 2014）, threatening he...Dear Editor, Coxsackievirus A16 （CV A16） and enterovirus 71 （EV71） are currently the two primary causative agents of hand- foot-and-mouth disease （HFMD） （Solomon et al., 2010; Mao et al., 2014）, threatening health of children world- wide. They both belong to the Enterovirus genus of the Picornaviridae family, and have single-stranded positive- sense RNA genomes of about 7.5 kilobases （kb） in length. As with other positive-strand RNA viruses, the genome rep- lication process ofCV A16 is carried out by a membrane- associated replication complex with the virally encoded RNA-dependent RNA polymerase （RdRP） as the essential catalytic enzyme.展开更多
基金Project(20203015) supported by the National Natural Science Foundation of China Project supported by the State Key Laboratory for Corrosion and Protection of China
文摘The nickel electroplating process was investigated by means of electrochemical noise(EN), cyclic voltammetry in conjunction with the scanning electron microscopy(SEM) technique. The results show that, in the experimental conditions and with the increase of current density, the growth mechanism of nickel crystallites changes from 2-D to 3-D with the potential turning point of about -1.15 V, and the potential for the onset of diffusion control of the ensemble nickel electroplating process was about -1.4 V. In the case of activation-control, the two-dimensional (2-D) nucleation / growth process of nickel often results in the electrocrystallization EN features of only slowly small positive potential drift and the corresponding compact layer-by-layer deposit structure, and the maximum relative energy of the RP-EDP (re-plotted relative energy distribution plot), which is obtained from wavelet analysis, defined in the region with smaller scales. While under the diffusion-control, the three-dimensional (3-D) nucleation / growth process of nickel, often results in the electrocrystallization EN features of both the fast positive potential drift and subsequent remarkable negative potential drift and the corresponding dentritic/large conglomerate structure of nickel deposit, and the maximum relative energy of the RP-EDP defined in the region with larger scales. The electroplating time affects the nickel deposit structure mainly through its influence on the growth rate of crystallites and the Ni2+ ions diffusion process around each crystallite.
基金the National Natural Science Foundation of China(No.40776060)the Program for Innovative Research Team in Science and Technology in Fujian Province University.
文摘Pig pancreas ferritin（PPF） was purified by ultra-centrifugation, ion-exchange chromatography, and native gradient polyacrylamide gel electrophoresis（PAGENG）. Sodium dodecyl sulfate（SDS）-PAGE indicates that PPF consists of two subunit types, namely, H（21000） and L（19000） subunits, and its core shows an average element composition of 1698 Fe3＋ and 179 phosphate molecules within the hollow shell, giving a 9.5：1 ratio of Fe3＋ to phosphate. An off line approach combining reversed-phase high-performance liquid chromatography（RP-HPLC） with matrix-assisted laser desorption ionization time of flight mass spectrometry（MALDI-TOF MS） made the decomposition of PPF shell into H and L subunits for the analysis of mass spectrometry（MS）, giving molecular weights of both H（21014.4） and L（18319.9） subunits. Both subunit types were further identified by an approach combining peptide mass fingerprint（PMF） with database search. A ratio of 1H to 2L subunits in PPF was determined by SDS-PAGE, RP-HPLC, and MALDI-TOF MS, respectively. It is well known that the non-covalent interaction of L-L or H-L subunits is stronger than that of H-H subunits in PPF, which may be further used to explain the unclear physiological function between H and L subunits in PPF.
文摘针对室内环境基于RSSI定位不稳定问题,提出了以几何信息改进基于指纹库的KNN定位算法。根据室内几何布局建立了聚类指纹库,提出了表征点位几何特性的点散发性强度(geometric strength of sporadic,GSS)概念。利用最邻近样本点的GSS判别移动终端所在参考点RP控制网结构以动态选择KNN关键参数K,构建最佳多边形为约束准则自适应选取后K-1个邻近点,建立了基于几何聚类指纹库的约束加权KNN室内定位模型。结果表明,改进后定位模型可以更好地估计终端位置信息,其中几何聚类指纹库是改善定位准确性的关键,约束KNN能够有效地提高室内定位精度。
基金This work was supported by the National Basic Research Program of China (2003CB415002) and the China Postdoctoral Science Foundation (No. 2003033486) and the Natural Science Research Fund of University in Jiangsu (04KJB150149)
文摘Sixteen indole derivatives have been computed at B3LYP/6-31 IG^＊＊ level using density functional theory （DFF）. Based on linear solvation energy theory, the structural parameters were employed to present correlation between the parameters of chromatograph capacity factor （CCF） and molecular structural parameters. As a result, the correlation equation of the reversed phased high performance liquid chromatograph capacity factor to the intercept lgk＇w and slope S of CCF were obtained, from which the correlation coefficients of lgk＇w to the structural parameters are r^2 = 0.9596 and q^2 = 0.9262. While the correlation coefficients of the parameter S r^2 q^2 with structures are = 0.9750 and = 0.9252. Moreover, the effect of water as solvent on the present two models was also considered using SCRF method, and the result shows that the predicting capacity of correlation equation of lgkw＇ increases, while that of the model for S decreases slightly. Both two correlation equations achieved in this work are more advantageous than those using theoretical descriptors from molecular connectivity indices.
文摘A study has been carried out of evaluating lipophilicity of some 1 1, 2, 4 triazole compounds by RP HPTLC. An equation that reasonably correlates partition coefficients( c lg P ) with R M 0 values for 23 \{1 1,2,4 triazole\} compounds was derived and its predictive capability was tested with five 1 1,2,4 triazole compounds. It has been found that RP HPTLC can be extensively applied to determining lipophilicity of \{1 1,2,4 triazole\} compounds.
文摘Dear Editor, Coxsackievirus A16 （CV A16） and enterovirus 71 （EV71） are currently the two primary causative agents of hand- foot-and-mouth disease （HFMD） （Solomon et al., 2010; Mao et al., 2014）, threatening health of children world- wide. They both belong to the Enterovirus genus of the Picornaviridae family, and have single-stranded positive- sense RNA genomes of about 7.5 kilobases （kb） in length. As with other positive-strand RNA viruses, the genome rep- lication process ofCV A16 is carried out by a membrane- associated replication complex with the virally encoded RNA-dependent RNA polymerase （RdRP） as the essential catalytic enzyme.
