用正交设计制作酶过程曲线的方法

用正交设计制作酶过程曲线的方法郭慧云，张立，李彬，刘兰英（吉林大学分子生物学系，长春１３００２３）正交设计￣［１］，是用正交表安排多因素试验、用统计数学原理进行数据分析的一种科学方法。为培养学生的实际工作能力，应让本科生在专门化实验课中得到使用该方法...     

烟用水基胶中2,2,4-三甲基-1,3-戊二醇二异丁酸酯增塑剂含量的测定

通过正己烷振荡提取烟用水基胶中的2，2，4-三甲基-1，3-戊二醇二异丁酸酯（TXIB），采用气相色谱-质谱/选择离子监测法分析烟用水基胶中的TXIB，内标法定量.结果表明：方法的线性相关系数为0.999 7，检出限为0.75 μg/mL，RSD为1.78%，回收率在95.3%~103.1%之间，说明方法的线性良好、检出限低、重复性好、准确性高，适于烟用水基胶中TXIB的测定.     

原子吸收光谱法测定电解铜中微量锡和锑

建立了用偏振塞曼原子吸收光谱法测定电解铜中微量元素锡、锑含量的方法。本方法用硝酸溶解样品，所得试样用空气-乙炔火焰原子吸收光谱法测定，工作曲线法定量。测定结果满意。     

对“空气中氧气含量测定实验”的改进

通过文献研究和实验研究，得出用吸氧腐蚀原理测量空气中氧气含量，比传统用红磷燃烧测量空气中氧气含量的方法更加科学、准确，并提出改进方案。     

直流电沉积Ni-Al2O3纳米阵列体系结构与性能

用直流电沉积的方法成功地将Ni金属填入了用二次腐蚀方法制备的氧化铝模板纳米级孔洞中，分别用电子显微镜、X射线衍射仪和振动样品磁强计对Ni阵列体系进行结构观察和磁性表征.结果表明，用二次腐蚀方法制得的多孔氧化铝模板的孔洞排布的有序性很高.被组装的Ni呈单晶结构并具有一定的择优取向； Ni-Al2O3阵列体系有明显的垂直磁各向异性，适用于垂直磁记录介质.     

氢化物发生－ICP发射光谱法测定饮用水中痕量砷

本文提出用简易氢化物发生系统与ＩＣＰ光谱仪联用，测定自来水和矿泉水中痕量砷的简易、快速的方法。用氢氧化铁共沉淀水中痕量砷，沉淀用离心机分离和富集。选择最优化的反应条件和工作条件。方法的检测限为０．００２μｇ／Ｌ，精密度为２％，回收率在９０％～１０４％之间。     

羊组织中溴氰菊酯残留量的测定

用５０ｍｇ／Ｌ溴氰菊酯水溶液池浴１２只绵羊，浴后每批宰杀３只。取其肝、肾、肌肉、网状 肪和肾周围脂肪，用无水乙醚，正己烷提取，用高效液相色谱分离制备，再用气相色谱测定其溴氰菊酯的残留量，方法的回收率大于０．５％，最小检出限为０．０５ｎｇ。     

壳聚糖膜的量子化学计算

采用Gaussian92程序，用AM1半经验量子化学方法优化壳聚糖膜模型的分子结构，在此基础上用量子化学从头算STO-3G方法计算，研究了壳聚糖-戊二醛的阳离子膜和阴离子膜的几何构型、能量、键序和电子迁移，讨论了膜形成的成键形式和膜的结构及稳定性     

甲鱼油脂肪酸组成的研究

用热提取方法抽取出甲鱼油，用ＫＯＨ－ＣＨ３ＯＨ酯交换法甲酯化处理，以色谱／质谱方法测定脂肪酸的组成。共鉴定出２１种脂肪酸，其中以棕榈酸、棕榈油酸、硬脂酸、油酸、亚油酸、二十碳五烯酸（ＥＰＡ）、二十二碳五烯酸（ＤＨＡ）为主     

α,β—二甲基脱水丙酮联苯酰的合成

用两种改进的方法，由联苯甲酰与３－戊酮反应制得α、β－二甲基脱水丙酮联苯酰（１），其结构由熔点、ＩＲ、ＨＮＭＲ确定，从ＨＮＭＲ谱推测：用乙醇作溶剂，加入ＫＯＨ、联苯甲酰及３－戊酮，于室温搅拌３ｈ后放置３天，所得ＩＡ为两对对映体；用苯作溶剂，加入适量聚乙二醇４００（ＰＥＧ４００），其它反应物同方法１，加热回流３ｈ，所得产物ＩＡ仅为一对对映体，改进的方法都缩短短了反应时间，上述两种方法得到的产物，经脱     

Friedel-Crafts Polymers. 6. Friedel-Crafts Polycondensation of p-Xylylerte Dibromide with Salicylic Acid and β-Resorcyiic Acid

Polymers were prepared by condensing p-xylylene dibromide separately with salicylic acid and β-resorcylic acid in the presence of anhydrous ferric chloride in dioxane. The polymer samples_were characterized by elemental analysis, by IR spectral study, by M determined by vapor pressure osmometry, by nonaqueous conducto-metric titration in pyridine, by TGA in air, and by viscosity measurements of polymer solutions in DMF. Polymeric metal chelates of Cu²⁺, Co²⁺, Zn²⁺, Ni²⁺, and Fe³⁺ with polymer samples were prepared and characterized by elemental analysis, by IR spectral study, and by TGA in air. The chelation ion-exchange properties of the polymer samples were studied by employing the batch equilibration method.     

Akt is involved in the inhibition of cell proliferation by EGF

Axin is a negative regulator of the Wnt/beta-catenin pathway and is involved in the regulation of axis formation and proliferation. Involvement of Axin in the regulation of other signaling pathways is poorly understood. In this study, we investigated the involvement of Akt in growth regulation by Axin in L929 fibroblasts stimulated by EGF. Akt activity was increased by EGF treatment and Ras activation, respectively. Both the EGF- and Ras-induced Akt activations were abolished by Axin induction, as revealed by both Western blot and immunocytochemical analyses. The proliferation and Akt activation induced by EGF were decreased by Axin induction, and the effects of EGF were abolished by treatment of an Akt-specific inhibitor. Therefore, Axin inhibits EGF-induced proliferation of L929 fibroblasts by blocking Akt activation.     

Fermented Oyster Extract Attenuated Dexamethasone-Induced Muscle Atrophy by Decreasing Oxidative Stress

It is well known that oxidative stress induces muscle atrophy, which decreases with the activation of Nrf2/HO-1. Fermented oyster extracts (FO), rich in γ-aminobutyric acid (GABA) and lactate, have shown antioxidative effects. We evaluated whether FO decreased oxidative stress by upregulating Nrf2/HO-1 and whether it decreased NF-κB, leading to decreased IL-6 and TNF-α. Decreased oxidative stress led to the downregulation of Cbl-b ubiquitin ligase, which increased IGF-1 and decreased FoxO3, atrogin1, and Murf1, and eventually decreased muscle atrophy in dexamethasone (Dexa)-induced muscle atrophy animal model. For four weeks, mice were orally administered with FO, GABA, lactate, or GABA+Lactate, and then Dexa was subcutaneously injected for ten days. During Dexa injection period, FO, GABA, lactate, or GABA+Lactate were also administered, and grip strength test and muscle harvesting were performed on the day of the last Dexa injection. We compared the attenuation effect of FO with GABA, lactate, and GABA+lactate treatment. Nrf2 and HO-1 expressions were increased by Dexa but decreased by FO; SOD activity and glutathione levels were decreased by Dexa but increased by FO; NADPH oxidase activity was increased by Dexa but decreased by FO; NF-κB, IL-6, and TNF-α activities were increased by Dexa were decreased by FO; Cbl-b expression was increased by Dexa but restored by FO; IGF-1 expression was decreased by Dexa but increased by FO; FoxO3, Atrogin-1, and MuRF1 expressions were increased by Dexa but decreased by FO. The gastrocnemius thickness and weight were decreased by Dexa but increased by FO. The cross-sectional area of muscle fiber and grip strength were decreased by Dexa but increased by FO. In conclusion, FO decreased Dexa-induced oxidative stress through the upregulation of Nrf2/HO-1. Decreased oxidative stress led to decreased Cbl-b, FoxO3, atrogin1, and MuRF1, which attenuated muscle atrophy.     

湿化学法制备硅纳米线阵列及其光电化学产氢性能分析

为了探究不同方法条件下制备的硅纳米线阵列电极产氢性能异同,文中分别采用了两步金属辅助催化无电刻蚀法、一步金属辅助催化无电刻蚀法以及阳极氧化法来制备硅纳米线阵列用作为光电分解水电池光阴极材料。通过FESEM、XRD和UVVis-IR DRS等手段对实验样品的形貌、晶型、减反性表征,发现相比于其他2种方法所得硅纳米线样品,两步金属辅助催化无电刻蚀法制备的硅纳米线结构晶型保持更好,表面缺陷更少。光电化学测试表明两步金属辅助催化无电刻蚀法制备的硅纳米线光电化学性能表现最优,其光电流密度值是一步法的4倍,阳极氧化法的40倍;转移电荷电阻仅是一步法制备的硅纳米线阵列阻值的1/3,阳极氧化法制备的1/1 000。     

Substoichiometric determination of phosphorus

Phosphorus in orchard leaves (NBS SRM-1571) and spinach (SRM-1570) was determined by various substoichiometric analytical methods such as the direct method, GRASHCHENKO's method and the method of carrier amount variation. All samples were labelled with³²P radioisotope. The data obtained by the method of carrier amount variation were also treated by the method of least squares instead of De VOE's method. Phosphorus concentration in orchard leaves was 0.206±0.011% by the direct method, 0.219±0.011% by GRASHCHENKO's method, 0.211±0.011% by the method of carrier amount variation and 0.207±0.007% by the method of least squares, respectively. These values agree with the value reported by NBS (0.21±0.01%). Furthermore, these concentrations obtained by various substoichiometric methods were compared with those by radioactivation reported in a prevoius paper.     

Comparison of monolithic approaches for enantioselective capillary electrochromatography involving cyclodextrins

The access to CD-modified monoliths for enantiomeric separation by CEC can be divided into two main approaches. (i) Silica-based monoliths, prepared by either a sol-gel process or by sintering of silica particles, are modified after fabrication by coating with a CD selector. Alternatively the fusion of CD functionalized silica particle via gluing is feasible. (ii) Rigid or homogeneous organic polymer-based monoliths, prepared by polymerization of organic monomers in the presence of a porogen, are modified with the CD selector either by copolymerization or by physical incorporation into the continuous bed.     

锰离子控制掺杂二氧化钛薄膜光催化活性增强的机理探讨

采用溶胶-凝胶法通过工艺控制制备了锰离子以不同形式掺杂TiO₂的光催化剂薄膜,并通过XPS和SEM对薄膜的结构进行表征.通过UV-Vis分光光度计及电化学工作站表征了薄膜的光吸收性能和光电化学性能,通过甲基橙溶液的光催化降解脱色率来表征催化剂薄膜的光催化活性.结果表明,以锰离子MT掺杂方式制备的TiO₂薄膜可明显增强TiO₂的光催化活性,而以MM掺杂方式制备的TiO₂薄膜反而降低了TiO₂的光催化活性;锰离子MT掺杂方式的最佳掺杂质量分数为0.8%.催化剂薄膜的电化学行为显示,薄膜具有p-n结的电容-电压特性,锰离子MT掺杂TiO₂薄膜的开路电位和瞬时光电流信号较强,说明其光生载流子易于生成并且分离效果较好.依据半导体的p-n结原理探讨了锰离子控制掺杂TiO₂的光催化活性机理.     

铂修饰光阴极及其在纳晶太阳能电池中的应用

分别用真空镀膜法、热分解法和电化学法制备了铂金修饰导电玻璃,并以此作为光阴极组装了染料敏化纳晶TiO₂太阳能电池.用SEM观察了铂金修饰导电玻璃表面形貌,发现用真空镀膜法制备的铂金膜结构缺陷多、不均匀,存在较多的污点.用热分解法制备的铂金膜具有多孔状结构,但存在较多的有机物分解的残留物.用电镀法制备的铂金膜结构均匀、排列规则、缺陷少、污染少.测定了所制备铂金膜的电阻,结果表明由电镀法所制得的铂金膜电阻最小,用热解法和真空镀膜法制得的铂金膜电阻较大.测定了DSSC电池的光电性能,发现用电镀法制得的铂金膜的催化性能最好,大大提高了DSSC电池的性能;其次是热分解法,由真空镀膜法制备的铂金膜对电池的性能没有多大改善.     

Synthesis, properties, and applications of urethane-modified acrylated poly(ester-amide)s

Epoxy resin-based unsaturated poly(ester-amide) resins (UPEAs) were treated with acryloyl chloride to afford acrylated UPEAs resins (AUPEAs). Urethane-based acrylated poly(ester-amide)s prepared by reaction with diisocyanate were characterized by elemental analysis, by molecular weight determination (by vapour pressure osmometry), by IR spectral study, and by thermogravimetry. The curing of interacting blends was monitored by differential scanning calorimetry (DSC). On the basis of DSC data in-situ glass-reinforced composites were prepared from the resulting materials and their mechanical, electrical, and chemical properties were characterized. Unreinforced blends were characterized by thermogravimetry.