岭回归法解析病态光谱体系数据及其在复方维生素B分析中的应用

当多组分体系的吸收光谱出现严重重叠而构成病态体系时，用以最小二乘估计的各种化学计算学方法算其含量时，往往导致偏差，本文用岭回归法处理复方维生素Ｂ四组分体系的光谱数据，所得分析结果表明优于最二乘法。     

多元光度测定病态系统的岭回归估计

考察了含多种酚类的有机混合体系的同时测定，发现对于这类化学与光谱性质皆十分相近的混合物体系，最小二乘法和卡尔曼滤波方法都不能给出令人满意的结果，甚至出现负值，而脾岭回归估计方法对此类病态体系进行分析，所得结果明显优于最小二乘法与卡尔曼滤波方法。     

多元分辨校正模型与方法研究—无机多组份分析

系统研究了各种多元分辨校正模型、方法及其应用，以模拟体系、病态体系有态体系为对象，考察了它们的多元校正能力与多元分辨效果，给我机多组份分析态体系实例。     

处理滴定分析中几个问题的体会

介绍应用简单酸碱体系扩展、广义酸碱平衡、广义络合效应和查漏补缺等方法处理滴定分析理论中平衡体系组分分布、副反应系数和综合性习题解析等问题的体会。     

流动注射-阻尼最小二乘法用于多组分分析

研究了用流动注射分析进行阻尼最小二乘分光光度法同时测定锌、铜和钴的新方法。方法基于阻尼最小二乘法改进CPA法，将阻尼因子和非零截距引入CPA法，降低了P系数矩阵的病态程度和改善了校正模型的预报能力，使结果更加准确，已将方法成功用于锌铜钴混合体系的分析。     

表征波与流相互作用的广义E-P通量

本文给出了含有大气层结效应的、并用观测资料可直接去诊断纬向平均流加速的广义E-P通量关系。它的优点在于,即使在大气斜压性较强,瞬变扰动的热量输送随时间和空间有明显变化的情况下,波对纬向平均流的加速作用也能较好地被诊断出来。同时广义E-P通量中,自动解除了过去E-P通量中存在的病态条件及扰动位移η’的不确定性,它能较准确地用观测资料去判别。文中用实例说明了广义E-P通量能诊断出一般E-P通量所不能正确诊断出来的结果。     

广义流态化中双组份颗粒的分级与混合

本文对广义流化体系的分级与混合进行了理论分析。在前人的工作基础上得出了广义流化体系分级与混合的数学模型。设计制做了一个结构紧凑的二维广义流化床。用该设备共对下列四个双粒体系在不同流化条件下的分级与混合规律进行了实验研究。     

一种测定中药复方制剂中活性成分的计算分析方法

提出了一种测定中药复方制剂中活性成分含量的计算分析新方法。该方法将主 成分分析和广义秩消因子分析集成用于处理HPLC／DAD数据，并改进了传统的IND因 子指示函数，适用于定量计算分析复杂混和物体系中的待测成分。将其用于测定复 方丹参制剂中三七皂苷R1的含量，计算分析结果表明，本方法明显优于广义秩消因 子法，同时证明IND函数的改进提高了计算分析准确度。     

6种化学计量学法同时分光光度测定5组分的比较研究及食品分析

优化了在表面活性剂存在下以肉桂基荧光酮同时测定铝、铜、锰、锌、钴的显色折衷条件；比较研究了偏最小二乘、岭回归、多元线性回归、多元逐步回归、目标因子分析和卡尔曼滤波法用于这一体系同时测定此５组分的优缺点，结果表明对于此类所含各组分吸收光谱重叠严重且吸光度加和性欠佳体系，上述６法中以偏最小二乘和岭回归法为最适宜；经用于九种人工合成液和四种食品分析，均获满意结果，分析两种茶叶结果也与ＩＣＰ－ＡＥＳ法一致     

铜及其配合物在生物体系中的作用

自人类有历史记载以来，铜及其配合物即用作药物。铜是人体必需的金属元素。人体的正常代谢过程需要它们，但无法体内合成，因此，需要每天从饮食摄取和吸收。生物药学家和研究者以极大的努力彻底地了解铜及其配合物在生物体系中的作用，希望获得更多地信息以利于人类疾病的预防和治疗。本综述评述了铜在组织中的分配和代谢、铜依赖酶、在病态时铜的非正常代谢、铜配合物的药疗活性和抑制氧自由基的产生。     

超高效液相色谱法结合化学计量学分析评价4种商品人参的质量

建立了快速、灵敏、准确的超高效液相色谱方法,用来分析4种商品人参(人参、红参、人参叶、人参须)中12种人参皂苷的含量,并用化学计量学方法评价了商品人参的质量。采用ACQUITY UPLC^TM BEH C₁₈色谱柱(50 mm×2.1 mm, 1.7 μm),以乙腈-水为流动相进行梯度洗脱。对所建立的测定12种人参皂苷的UPLC方法进行了线性方程、准确度、重复性、回收率等方法学考察。采用聚类分析和主成分分析的化学计量学方法对4种商品人参进行分析,评价了其质量。结果表明聚类分析和主成分分析2种化学计量学方法非常适合大样本、多成分的中药材质量分析。     

Novel Carbon Dots Derived from Glycyrrhizae Radix et Rhizoma and Their Anti-Gastric Ulcer Effect

Glycyrrhizae Radix et Rhizoma (GRR) is one of the commonly used traditional Chinese medicines in clinical practice, which has been applied to treat digestive system diseases for hundreds of years. GRR is preferred for anti-gastric ulcer, however, the main active compounds are still unknown. In this study, GRR was used as precursor to synthesize carbon dots (CDs) by a environment-friendly one-step pyrolysis process. GRR-CDs were characterized by using transmission electron microscopy, high-resolution TEM, fourier transform infrared, ultraviolet-visible and fluorescence spectroscopy, X-ray photoelectron spectroscopy, X-ray diffraction and high-performance liquid chromatography. In addition, cellular toxicity of GRR-CDs was studied by using CCK-8 in RAW264.7 cells, and the anti-gastric ulcer activity was evaluated and confirmed using mice model of acute alcoholic gastric ulcer. The experiment confirmed that GRR-CDs were the spherical structure with a large number of active groups on the surface and their particle size ranged from 2 to 10 nm. GRR-CDs had no toxicity to RAW264.7 cells at concentration of 19.5 to 5000 μg/mL and could reduce the oxidative damage of gastric mucosa and tissues caused by alcohol, as demonstrated by restoring expression of malondialdehyde, superoxide dismutase and nitric oxide in serum and tissue of mice. The results indicated the explicit anti-ulcer activity of GRR-CDs, which provided a new insights for the research on effective material basis of GRR.     

Low-cost evaluation of the exchange Fock matrix from Cholesky and density fitting representations of the electron repulsion integrals

The authors propose a new algorithm, "local K" (LK), for fast evaluation of the exchange Fock matrix in case the Cholesky decomposition of the electron repulsion integrals is used. The novelty lies in the fact that rigorous upper bounds to the contribution from each occupied orbital to the exchange Fock matrix are employed. By formulating these inequalities in terms of localized orbitals, the scaling of computing the exchange Fock matrix is reduced from quartic to quadratic with only negligible prescreening overhead and strict error control. Compared to the unscreened Cholesky algorithm, the computational saving is substantial for systems of medium and large sizes. By virtue of its general formulation, the LK algorithm can be used also within the class of methods that employ auxiliary basis set expansions for representing the electron repulsion integrals.     

Expression of Cholera Toxin B–Lumbrokinase Fusion Protein in Pichia pastoris—The Use of Transmucosal Carriers in the Delivery of Therapeutic Proteins to Protect Rats Against Thrombosis

Cholera toxin B-subunit (CTB) has been widely used to facilitate antigen delivery by serving as an effective mucosal carrier molecule for the induction of oral tolerance. However, whether CTB can be used as a transmucosal carrier in the delivery of not only vaccines but also therapeutic proteins has not been widely studied. Thus, we investigate here the concept of receptor-mediated oral delivery of lumbrokinase (LK) proteins which is an important fibrinolytic enzyme derived from earthworm. CTB and LK, separated by a furin cleavage site, was expressed via Pichia pastoris. The activity and proper folding of recombinant protein in yeast were confirmed by Western blot analysis, fibrin plate assays, and G_M1-ganglioside ELISA. Following oral administration of recombinant protein, the thrombosis model of rats and mice revealed that the oral treatment of rCTB–LK has a more significant anti-thrombotic effect on animals compared with rLK. It is possible to conclude that CTB can successfully enhance its fusion protein LK to be absorbed. The use of CTB as a transmucosal carrier in the delivery of not only vaccines but also therapeutic proteins was supported.     

Facile Synthesis of AuPd Nanochain Networks on Carbon Supports and Their Application as Electrocatalysts for Oxygen Reduction Reaction

The present work reports the facile synthesis and characterization of carbon‐supported porous Pd shell coated Au nanochain networks (AuPdNNs/C). By using Co nanoframes as sacrificial templates, AuPdNNs/C series have been prepared by a two‐step galvanic replacement reaction (GRR) technique. In the first step, the Au metal precursor, HAuCl₄, reacts spontaneously with the formed Co nanoframes through the GRR, resulting in Au nanochain networks (AuNNs). The second GRR is performed with various concentrations of Pd precursor (0.1, 1, and 10 mM PdCl₂), resulting in AuPdNNs/C. The synthesized AuPdNNs/C series are investigated as electrocatalysts for oxygen reduction reaction (ORR) in alkaline solution. The physical properties of the AuPdNNs/C catalysts are characterized by scanning electron microscopy (SEM), high‐resolution transmission electron microscopy (HRTEM), UV‐vis absorption spectroscopy, and cyclic voltammetry (CV). Rotating disk electrode (RDE) voltammetric studies show that the Au_0.8Pd_0.2NNs/C (prepared using 1 mM PdCl₂) has the highest ORR activity among all the AuPdNNs/C series, which is comparable to commercial Pt catalyst (E‐TEK). The ORR activity of AuPdNNs/C is presumably due to the enhanced Pd surface area and high porosity of Pd nanoshells.     

The calculation of equilibrium concentrations in large multimetal/multiligand systems

An algorithm for computing equilibrium concentrations by the “equilibrium constant” method is described. The main features of this algorithm are: (a) a damping procedure in conjunction with the Newton-Raphson technique that avoids divergence in dealing with very complicated (simultaneous presence of simple, mixed, protonated, polynuclear and hydroxypolynuclear species) and/or very large systems; (2) the use of devices to decrease core requirements, calculation time, and ill-conditioned problems; and (3) the calculation of errors in free and species concentrations from the uncertainties in analytical concentrations and in formation constants. Four systems are used for testing computer programs on calculation of equilibrium concentrations.     

Lemniscular hexaphyrins as examples of aromatic and antiaromatic double-twist Möbius molecules

Two reported [26] and [28]hexaphyrins are analyzed via measured and computed geometries and NMR-shieldings as examples of respectively 4n + 2 pi-electron aromatic and 4n pi-electron antiaromatic double-twist M?bius ring systems, adopting a lemniscular/figure-eight topology with linking number LK = 2pi. Values of local twist (TW) and nonlocal writhe (WR) derived from the relation Lk = Tw + WR appear relatively insensitive to the aromatic/antiaromatic character. The [26]hexaphyrin may adopt differing solution and solid-state conformations.