牛奶蛋白质含量的SSA-SVM高光谱预测模型

牛奶中包含着很多人体需要的营养元素,如脂肪、蛋白质、钙等;对牛奶营养元素进行分析是牛奶安全检测关键的一部分.高光谱技术可以有效地结合图像和光谱数据识别牛奶种营养元素.为了实现对牛奶中蛋白质含量快速、精确的预测,采用竞争性自适应重加权(CARS)算法选取特征波长,并提出一种基于麻雀搜索算法(SSA)优化支持向量机(SVM...     

不同粒径对土壤有机质含量可见—近红外光谱预测的影响

土壤有机质(SOM)是表征土壤肥力的重要指标,实现其快速准确检测可为精准农业区域管理提供有效的数据支撑。土壤粒径对SOM 的光谱预测及仪器开发有很大的影响,为了明确不同粒径对 SOM 预测的影响,分别制备了1～2,0.5～1,0.25～0.5,0.1～0.25和<0.1mm 五种均匀粒径及<1mm 混合粒径共计6种粒径土样并进行了可见-近红外(300～2 500nm)光谱数据采集。采用蒙特卡罗交叉验证分别剔除了不同粒径的异常样本,结合Savitzky-Golay卷积平滑法对光谱数据进行平滑去噪处理,比较了不同粒径样品的光谱反射率差异,并对平滑后的原始光谱 R进行倒数IR、对数 LR、一阶导数 FDR等3种光谱变换并分析与SOM 含量的相关性,基于竞争性自适应重加权算法(CARS)对光谱数据进行了特征波长提取,并结合偏最小二乘回归(PLSR)分别建立了相应的SOM 含量预测模型。结果表明,不同粒径土样的平均光谱反射率与变异系数随着粒径的减小逐渐增加,且在大于540nm 波长范围内,差异明显。随着粒径的减小,SOM含量与光谱反射率在全波段范围的相关性变化幅度愈加明显,FDR 变...     

人工神经网络分类鉴别苦丁茶红外光谱

为了分类鉴别苦丁茶,采用竞争神经网络(CNN)和反向传播人工神经网络(BP网络)两种模式的人工神经网络(ANN)分别分析了各种苦丁茶的红外谱图。作者采用25个样本作训练集,11个样本作检验集,用两种网络进行了训练。结果表明,CNN网络和BP网络均能够有效地实现苦丁茶产地的鉴别,但CNN网络能够进一步地区分苦丁茶的级别。实验表明,CNN速度快,预测结果准确,可望用竞争神经网络(CNN)和红外光谱法结合分类鉴别苦丁茶。     

Business planning for a profit-seeking insurer under deficiency of information

This paper aims to model a profit-seeking firm in a regulated competitive insurance market in an epoch when future annual market prices become poorly predictable. It occurs when more and more non-antagonistic contenders cut their prices seeking for individual success. It aggravates randomness pertaining to insurance casualties. This paper deals with multi-year control strategy of a profit-seeking insurer aiming in this epoch to comply each year with legal solvency requirements, to keep its portfolio size more or less stable, and to keep business attractive for investments.     

Chemical braking exhibited by ethynylhelicene (M)-nonamer in solution: Competitive reaction system of self-catalysis to form double-helix and approach towards equilibrium to form random-coil

Chemical braking occurs in a dilute solution during a structural change of ethynylhelicene (M)-nonamer from the metastable double-helix state to the random-coil state, being at equilibrium, where the reaction is initially rapid and then substantially retard. The chemical braking is derived from the competitive chemical reaction system in dilute solution: An energetically uphill self-catalytic reaction to form double-helix and the downhill reaction to form the random-coil.     

环己烯对噻吩在CuY分子筛上吸附的影响机制

A CuY zeolite prepared by liquid phase ion exchange was characterized by X-ray photoelectron spectroscopy, pyridine in situ Fourier transform infrared (in situ FTIR) spectroscopy, and ammonia temperature programmed desorption. The effect of cyclohexene on the adsorption of thiophene over the prepared CuY zeolite was explored by in situ FTIR. In particular, the role of the zeolite's Br?nsted acidity was investigated in the adsorption process. The results show that the percentage of Cu⁺ on the surface of the CuY zeolite can reach 77%. The surface acidity of the CuY zeolite mainly comprises medium and strong Br?nsted acidity and Lewis acidity. According to the adsorption results, cyclohexene negatively influences thiophene adsorption on the Br?nsted or Lewis acid sites in CuY by competitive adsorption. Although polymerization of thiophene and cyclohexene can occur easily on the HY or REY zeolites, the presence of Br?nsted acids in the CuY zeolite was not sufficient to polymerize either thiophene or cyclohexene. This difference may be caused by an anti-synergistic effect between the Cu ions of the CuY zeolite and neighboring Br?nsted acid sites, the result of which inhibits the polymerization of adsorbed thiophene and cyclohexene.     

非水体系中吡啶和乙腈在铂电极上竞争吸附的表面增强拉曼光谱研究

继非水体系中CO在过渡金属表面吸附的表面增强拉曼光谱（SERS）研究之后，本文是又一篇关于非水体系中过渡金属表面SERS研究的文章。从拉曼谱峰的变化结果发现，吡啶在Pt电极表面是强烈的化学吸附，并且由于其吸附的量和吸附取向随电位在不断地变化，与水体系中吡啶（Py)在Pt电极表面的吸附相比较，SERS谱峰除了强度较低之外，在可研究的电位区间、谱峰位置以及其随电位变化等方面都存在着不同，这缘于结构较为复杂的有机溶剂分子在电极表面组成了更为复杂的界面结构，造成固／液界面的电迁移等电极动力学过程发生了变化，为了说明这一现象，文中还采用强吸附离子I^-进行研究，得到相似的结果。     

Scavenging of Priority Organic Pollutants from Aqueous Waste Using Granular Activated Carbon

Compliances with stringent effluent discharge limits imposed by environmental protection agencies (EPA) and the most economic way of achieving it without loss of production has led to continued refinement, recognition and development of promising wastewater treatment technologies. Many organic compounds present in industrial and domestic wastewaters are carcinogenic in nature. Removal of these organic compounds from wastewater has become a great challenge to wastewater treatment technologies, as many of them are non‐biodegradable in nature. Adsorption on granular activated carbon (GAC) has emerged an efficient and economically viable technology for removal of final traces of a broad spectrum of toxic organic compounds from domestic and industrial wastewater. In the present investigation adsorption of some priority organic pollutants, namely phenol, o‐cresol, p‐nitrophenol, m‐methoxyphenol, benzoic acid and salicylic acid on granular activated carbon, was studied in a batch system at laboratory scale. Experiments were carried out to determine adsorption isotherms and kinetics for adsorbate when present in aqueous solutions as single, bi‐ and tri‐solute systems. The commercially available bituminous coal based granular activated carbon Filtrasorb 300 (F‐300) was used as adsorbent. The results indicate that p‐nitrophenol is most strongly adsorbed as compared to other phenols studied. Aqueous phase solubility of the adsorbate plays a deciding role in multi‐component systems as more hydrophobic p‐nitrophenol adsorbs to a greater extent than less hydrophobic phenol, o‐cresol and m‐methoxyphenol. The preferential adsorption of strongly adsorbable solute over a weakly adsorbable one has been observed, as the solutes are competing for the available surface area of the adsorbent for adsorption.     

Competition-reachability of a graph

The reachability r(D) of a directed graph D is the number of ordered pairs of distinct vertices (x,y) with a directed path from x to y. Consider a game associated with a graph G=(V,E) involving two players (maximizer and minimizer) who alternately select edges and orient them. The maximizer attempts to maximize the reachability, while the minimizer attempts to minimize the reachability, of the resulting digraph. If both players play optimally, then the reachability is fixed. Parameters that assign a value to each graph in this manner are called competitive parameters. We determine the competitive-reachability for special classes of graphs and discuss which graphs achieve the minimum and maximum possible values of competitive-reachability.