超高效液相色谱-串联质谱法测定水产品中孔雀石绿前处理方法的改进

采用超高效液相色谱-串联质谱法(UPLC-MS/MS)测定水产品中孔雀石绿的残留量,以GB/T 19857-2005检测方法为基础,将前处理步骤进行优化.称取5 g样品,加入质量浓度为100μg/L的内标标准溶液100μL,混匀,加入20 m L乙腈、5 g酸性氧化铝,震荡、离心,取4 m L溶液氮气吹干,用流动相定容至1 m L,过0.22μm滤膜,上机测试.按照标准方法测定标准曲线相关系数r:孔雀石绿为0.999,隐色孔雀石绿为0.999.孔雀石绿的回收率分别为71.7%、95.2%和89.9%,精密度分别为4.47%、4.26%和8.57%.隐色孔雀石绿的回收率分别为93.3%、98.8%和89.7%,精密度分别为8.73%、6.87%和9.71%.试验结果满足相关标准和体系文件的要求.     

Preprocessed barley,rye, and triticale as a feedstock for an integrated fuel ethanol-feedlot plant

Rye, triticale, and barley were evaluated as starch feedstock to replace wheat for ethanol production. Preprocessing of grain by abrasion on a Satake mill reduced fiber and increased starch concentrations in feedstock for fermentations. Higher concentrations of starch in flours from preprocessed cereal grains would increase plant throughput by 8–23% since more starch is processed in the same weight of feedstock. Increased concentrations of starch for fermentation resulted in higher concentrations of ethanol in beer. Energy requirements to produce one L of ethanol from preprocessed grains were reduced, the natural gas by 3.5–11.4%, whereas power consumption was reduced by 5.2–15.6%.     

Spectroscopic investigation of the donor-acceptor interaction between o-phenylenediamine and tetracyanoethylene in dichloromethane

The interaction between the electron donor o-phenylenediamine (o-phendn) and the pi-acceptor tetracyanoethylene (TCNE) has been investigated spectrophotometrically in dichloromethane at 25 degrees C. The results indicate that the reaction proceeds via two major steps. The formation of the 1:2 charge-transfer complex [(o-phendn)(2), (TCNE)(4)] in which two o-phenylenediamine molecules undergoes slow N-substitution by one TCNE forming the final reaction product 2,2-di-o-aminoaniline-1,1-dicyanoethylene and 2HCN molecules. The reaction was studied using electronic, infrared, photometric titration and cyclic voltametric measurements. A general mechanism for the reactions is proposed.     

Molecular dynamics modeling in quantum chemical calculations. Optical absorption spectra of 1,3-Dimethyl-1H-Pyrazolo[3,4-b]quinoline derivatives

Paper presents the quantum chemical modeling of the optical absorption spectra of 6-fluoro, 6-bromo, 7-trifluoromethyl, 6-cyano and 6-carboethoxy derivatives of 1,3-Dimethyl-1H-Pyrazolo[3,4-b]quinoline. The calculations are performed by means of the semiempirical quantum chemical methods (AM1 or PM3) in combination with molecular dynamics (MD) simulations at T=300 K. It is shown that a particular rotational dynamics of the methyl, trifluoromethyl or ethyl groups practically does not influence the optical absorption in the spectral range 200-500 nm whereas broadening of absorption bands may be well reproduced within MD simulations including all types of nuclei vibrations. The results of calculations are compared with the measured spectra of optical absorption. The quantum chemical method AM1 in combination with MD simulations gives for all dyes the best agreement between the calculated and measured spectral positions of the first absorption band (absorption threshold).     

基于LSTM的浮选钼精矿品位软测量模型

战略性稀有金属钼矿品位低,组分复杂、嵌布粒度细等特点,其有价金属分离回收难。浮选作为微细粒钼矿分离回收的主要选矿方法之一,其浮选钼精矿品位一直是选厂的关键性产品指标。国内大多数选厂采取轮班制采样,人工化验得到精矿品位结果,但此方式严重滞后于浮选工艺,难以满足对生产过程进行实时监测和操作指导。LSTM是一种特殊的循环神经网络,引入门机制有效的传递或选择性遗忘长时间序列中的信息,解决RNN中的长期依赖、梯度消失和爆炸问题。本文分析整理东坡选厂中各平台源数据,结合选厂浮选工艺及机理,筛选出多个影响浮选钼精矿品位的变量作为模型输入;将输入变量进行异常值判定,缺失值填充和数据降噪等数据预处理,建立高质量浮选钼精矿品位数据库;软测量模型采用PyCharm软件编码,使用BatchNorm批量规范化处理样本数据,加入Dropout正则化防止过拟合,建立基于LSTM的浮选钼精矿品位软测量模型,通过前向传播算法更新神经网络结构参数,并于Linear模型和CNN模型的预测性能指标结果比较。结果表明：基于LSTM的浮选钼精矿品位软测量模型预测准确度高,样本数据误差波动平稳,浮动范围小,模型泛化能力强,模型平均绝对百分比误差MAPE为1.13%,均方根误差RMSE为0.7049%,决定系数R2为0.8763,实现了浮选钼精矿品位的在线预测。     

Visualized attribute analysis approach for characterization and quantification of rice taste flavor using electronic tongue

This paper deals with a novel visualized attributive analysis approach for characterization and quantification of rice taste flavor attributes (softness, stickiness, sweetness and aroma) employing a multifrequency large-amplitude pulse voltammetric electronic tongue. Data preprocessing methods including Principal Component Analysis (PCA) and Fast Fourier Transform (FFT) were provided. An attribute characterization graph was represented for visualization of the interactive response in which each attribute responded by specific electrodes and frequencies. The model was trained using signal data from electronic tongue and attribute scores from artificial evaluation. The correlation coefficients for all attributes were over 0.9, resulting in good predictive ability of attributive analysis model preprocessed by FFT. This approach extracted more effective information about linear relationship between electronic tongue and taste flavor attribute. Results indicated that this approach can accurately quantify taste flavor attributes, and can be an efficient tool for data processing in a voltammetric electronic tongue system.     

Mononuclear and binuclear sandwich copper(II) complexes with poly(pyrazolyl)borate ligands: syntheses, structures and properties

A series of Cu(II) complexes Cu(2)[micro-pz](2)[HB(pz)(3)](2) (1), Cu[H(2)B(pz)(2)](2) (2), Cu[HB(pz)(3)](2) (3), Cu[HB(pz(Me2))(3)](2) (4), Cu[B(pz)(4)](2) (5) (pz=pyrazole), have been synthesized and characterized by elemental analysis, IR, UV-vis, X-ray diffraction, thermal analysis and theoretical analysis. The IR spectra give the Cu-N vibration modes at 322, 366, 344, 387, and 380 cm(-1) in complexes 1-5, respectively. The UV spectra show all the complexes have same UV absorption at 232 nm; there is another band at 332 nm for complexes 1, 2 and 4, while for complexes 3 and 5, the bands are at 272 and 308 nm, respectively. Complex 1 has a binuclear structure in which two pyrazole ligands bridge two Cu-Tp units. In 2-5, the Cu(II) centers are coordinated with dihydrobis(pyrazolyl)borate (Bp), hydrotris(pyrazolyl)borate (Tp), hydrotris(3,5-Me2pyrazolyl)borate (Tp'), tetrakis(pyrazolyl)borate (Tkp) respectively to form a mononuclear structure. The results of thermal analysis for complexes 1-5 are discussed too.     

含酰胺基团稀土配合物的红外光谱

本文合成了未见文献报道的氯化稀土丙酰胺配合物,剖析了ＬｎＣｌ３．３ＰＡ和聚（苯乙烯－丙烯酰胺）负载氯化稀土配合物（ＳＡＡ．ＬｎＣｌ３）的红外光谱和电子能谱,结果表明,含酰胺基团的配体均通过羰基氧与稀土离子配位。     

镧系四元混配化合物[Ln(BA)2(NO3)(phen)]2的合成、晶体结构和波谱研究

在酸性介质、含水溶剂中合成了四元混配化合物[Ln(BA)₂(NO₃)(phen)]₂(BA=苯甲酸根;Ln=La,Ce,Pr,Nd,Sm,Eu,Dy,Gd,Tb,Er),用元素分析、IR、DTA-TG等方法对配合物进行了表征.研究了配合物的顺磁性能和荧光性能.镨配合物的单晶衍射结果表明,配合物属三斜晶系,双核,Pr³⁺的配位数为9,4个BA呈二种配位方式,丰富了四元配合物的结构表现形式.     

波长40—60nm的高电离态硫离子某些能级跃迁谱线的实验研究

波长４０－６０ｎｍ的元素高电离态离子光谱实验中,观测到１０多条光谱线,这些谱线是ＳＸＩ到ＳＸⅣ离子的一些激发能级发射的,其中９条谱线还没有人报道实验结果,实验分析结果与理论符合得较好。