Rate effect and coupled evolution of atomic motions and potential landscapes

Since rate effect of materials plays a key role in impact engineering, the microscopic mechanism of rate effect is investigated at molecular level in this paper. The results show that rate effect on the strength of atomic system is closely related to the coupled evolution of atomic motions and potential landscapes. Accordingly, it becomes possible to develop a new algorithm of molecular simulation, which could properly and efficiently demonstrate strain rate effect under a wide range of loading rates and unveil the mecha- nisms underlying the strain rate effects.     

Accuracy Profile Theory for the Validation of an LC–MS-MS Method for the Determination of Risperidone and 9-Hydroxyrisperidone in Human Plasma

A sensitive and specific LC–MS-MS method is described for the simultaneous quantification of risperidone and 9-hydroxyrisperidone in human plasma. After extraction with tert-butyl methyl ether, plasma samples were separated on an Atlantis HILIC Silica C18 column (4.6 × 150 mm, 5 μm)with a mobile phase of ammonium formate buffer (10 mM, pH 4.0)/acetonitrile (40/60, v/v). Detection was by MS-MS. The method was fully validated according to the accuracy profile theory. It is based on β-expectation tolerance interval for the total measurement error which includes trueness and intermediate precision. The measurement uncertainty derived from β-expectation tolerance interval was estimated at each of the validation standards. The linearity fitted well over the range of 0.11–26.75 ng mL⁻¹ for risperidone with an LLOQ of 0.11 ng mL⁻¹, and for 9-hydroxyrisperidone, at a range of 0.15–37.8 ng mL⁻¹ with an LLOQ of 0.15 ng mL⁻¹. The intra- and inter-batch precision of risperidone were <5.71 and 8.22%, respectively. For 9-hydroxyrisperidone, the data were 5.78 and 6.48%. The recoveries were 88.78% (risperidone) and 70.35% (9-hydroxyrisperidone). The developed method was applied to a pharmacokinetic study of risperidone.

     

Terpenoids from Roots of Chloranthus spicatus

Five new terpenoids, including four eudesmane‐type sesquiterpenoids, 1 – 4 , and one labdane‐type diterpenoid, 6 , together with ten known compounds, were isolated from the roots of Chloranthus spicatus. The structures and their relative configurations were mainly established by 1D‐ and 2D‐NMR spectra, and MS experiments.     

基于多目标最优化混合按订单生产和提前生产策略库存模型算法

考虑了包含多阶段和多家零售商在内的混合按订单生产(Produce-to-Order)和提前生产(Produce-in-Advance)策略库存模型.将这一模型推广至多种产品情况下,当需求为正态分布时,将这一问题转化为一类多目标约束最优化问题,并给出两种算法来解决这一问题.     

非水溶液滴定法测定普卢利沙星的含量

以0.1mol.L-1高氯酸为滴定液,结晶紫为指示剂,用非水滴定法测定普卢利沙星。重复测定普卢利沙星含量平均值为99.4%(n=6),相对标准偏差为0.1%。该方法准确简便、重复性好,可作为普卢利沙星含量测定的有效方法。     

Supramolecular assembly of three d~(10) metal coordination polymers based on the naphthalene-1,8-dicarboxylate ligand:Syntheses,structures and luminescent properties

Three d10 tetranuclear complexes,Cd 4(1,8-nap) 4(2,2′-bipy) 4(H2O) 8·6H2O(1,8-nap=naphthalene-1,8-dicarboxylate and 2,2′bipy=2,2′-bipyridine)(1),Cd4(1,8-nap) 4(2,2′-bipy) 4(H2O) 8·6H2O(2) andZn4(1,8-nap) 4(2,2′-bipy) 4(H2O) 4·2H2O(3),have been synthesized under hydrothermal conditions and characterized by elemental analyses,IR and X-ray diffraction techniques. Complexes 1 and 2 are isomers showing one-dimensional ribbon-like structures connected by O-H···O hydrogen bonds,and the one-dimensional ribbons are ...