称重传感器蠕变误差的神经网络补偿方法

针对电阻应变式称重传感器存在严重的蠕变误差直接影响称重结果准确度的问题,提出了一种基于神经网络的称重传感器蠕变误差自动补偿模型,并给出了模型的训练算法。对量程为50 kg,C3等级的电阻应变式称重传感器进行了实验,实验结果表明,使用神经网络蠕变误差补偿方法补偿后,称重传感器加载标准砝码30 min内的蠕变误差最大变化量为0.0108 kg,小于国家标准GB/T 7551-200《称重传感器》规定的允许值。

Self-Similarity in Game-Locked Aggregation

A collective game is studied via agent-based modeling approach,where a group of adaptive learning players seek for their best positions on a vertical line.The movements of players are driven by benefits obtained from interactions.The game falls into an evolutionary stable state,at which aggregations of players on the line emerge.The pattern of these aggregates exhibits self-similarity at different scales with a fractal dimension of 0.58.The underlying mechanism of this aggregation is unique in that aggregates are resulted from mutual lock-in of players.This game-locked aggregation,in contrast with the diffusion limited aggregation,is applicable to a broader scope of aggregation processes.

Size Dependency of Income Distribution and Its Implications

We systematically study the size dependency of income distributions,i.e.income distribution versus the population of a country.Using the generalized Lotka--Uolterra model to fit the empirical income data for 1996-2007 in the U.S.A,we find an important parameter A that can scale with aβpower of the size(population)of the U.S.A.in that year.We point out that the size dependency of income distributions,which is a very important property but seldom addressed in previous studies,has two non-trivial implications:(1)the allometric growth pattern,i.e.the power-law relationship between population and GDP in different years,can be mathematically derived from the size-dependent income distributions and also supported by the empirical data;(2)the connection with the anomalous scaling for the probability density function in critical phenomena,since the re-scaled form of the income distributions has asymptotically exactly the same mathematical expression for the limit distribution of the sum of many correlated random variables.

Large Non-resonant Nonlinear Optical Susceptibility of Cu_(2)O Microcrystallites

We report the measured results of non-resonant nonlinearity by degenerate four-wave mixing for Cu2O nanopartides having central diameter of 9 nm.The value of x^(3) obtained in a 10ns pulse experiment is 8.48×1O^(-10) esu,and the nonlinear response time of the sample is estimated to be in the order of nanosecond.

HPLC法测定普瑞巴林纯度及其10个工艺杂质

目的:建立HPLC法检测苯乙胺工艺普瑞巴林原料药中的有关物质及纯度。方法:采用Inertsil ODS-3(150 mm×4.0 mm,3μm)色谱柱,以缓冲液(7.05 g磷酸二氢铵和1.45 g磷酸氢二铵溶于1000 mL水中)-甲醇-乙腈(900∶80∶20)为流动相A,乙腈为流动相B,进行梯度洗脱,流速0.8 mL·min^(-1),检测波长210 nm,柱温30℃,进样量50μL。结果:普瑞巴林峰与各杂质及降解产物峰能够完全分离(分离度>2.0),供试品溶液在48 h内稳定性良好;其他单杂(用普瑞巴林进行验证)、内酰胺、4-烯普瑞巴林、5-烯普瑞巴林、三聚物、3-异丁基戊二酸(PGB-3)、3-异丁基戊二酸单酰胺(PGB-5)、R-苯乙胺、4-异丁基-2,6-哌啶二酮(PGB-5B)、单酰胺苯乙胺(PGB-5C)、二酸苯乙胺(PGB-5D)的定量限分别为0.05%、0.01%、0.01%、0.03%、0.01%、0.05%、0.03%、0.01%、0.01%、0.01%和0.01%;其他单杂(用普瑞巴林进行验证)、内酰胺、4-烯普瑞巴林、5-烯普瑞巴林、三聚物、PGB-3、PGB-5线性相关系数均>0.99,范围为LOQ~各杂质指标150%;内酰胺、4-烯普瑞巴林、5-烯普瑞巴林、三聚物、PGB-3、PGB-5平均回收率(n=9)分别为100.6%(RSD=0.56%)、100.2%(RSD=0.38%)、100.5%(RSD=0.46%)、101.1%(RSD=1.1%)、100.0%(RSD=0.63%)、100.0%(RSD=0.54%);重复性和中间精密度符合规定。经检测,3批普瑞巴林原料药6个月加速和60个月长期稳定性各个杂质检测结果均符合质量标准。结论:该方法简便快速,灵敏度高,专属性强,可用于苯乙胺工艺普瑞巴林原料药中有关物质及纯度的检测。