401有机担体在非豆科树种固氮酶活性测定中的应用

<正> 应用乙炔还原法测定固氮酶的活性是一种既简单、灵敏,又经济快速的测试方法。因此,筛选分离乙炔与乙烯混合物效果良好的气相色谱柱是测定固氮酶活性的关键措施。早些时候,一般是在60—80目层析用氧化铝的表面涂渍上相当于其重量2%的阿匹松M,以此为固定相,填充入色谱柱使用,完成一次分析约需4分钟。近年来,随着高分子     

桑树不同方位叶片中葫芦巴碱含量测定

为解决利用分光光度法和极谱法测定植物中葫芦巴碱含量时时间较长,以及样品的制备和提取比较繁琐,操作复杂等问题,建立了高效液相色谱法测定桑树不同方位叶片中葫芦巴碱的含量方法。以氨基键和柱为固定相,甲醇和水为流动相,柱温为室温,可快速准确测定桑树叶片中葫芦巴碱含量。本方法样品预处理简单、分析灵敏度高、精密度好、速度快,尤其适应批量样品的分析。结果表明,桑树东南叶片中葫芦巴碱含量较高,西北叶片中葫芦巴碱含量较少,这可能与光照强度有关。     

高速逆流色谱法分离纯化白鲜皮中梣酮的初步研究

利用高速逆流色谱技术分离纯化白鲜皮中的梣酮,结果表明,选择V(正己烷):V(乙酸乙酯):V(乙醇):V(水)=1:1:1:1系统来分离,上相作为固定相,下相作为流动相,流速为1.5 mL/min,仪器转速1 000 r/min,分离结果经高效液相色谱(HPLC)检测纯度达到99%。     

萜烯邻苯二酚树脂-生漆共聚涂料研究(Ⅰ)--萜烯-邻苯二酚功能基树脂的分离提纯

以萜烯树脂和邻苯二酚为原料,合成了萜烯-邻苯二酚树脂.采用柱层析法分离萜烯树脂和萜烯-邻苯二酚树脂,分别采用中性氧化铝和强碱性阴离子交换树脂作固定相,汽油、乙醇、NaOH-乙醇溶液作洗脱剂对萜烯树脂和萜烯-邻苯二酚树脂进行分离提纯.通过对洗脱液进行紫外光谱分析,表明用中性氧化铝作固定相,分别用汽油、乙醇和NaOH-乙醇溶液洗脱,能较好地分离萜烯树脂和萜烯-邻苯二酚树脂.     

萜烯邻苯二酚树脂一生漆共聚涂料研究（Ⅰ）——萜烯-邻苯二酚功能基树脂的分离提纯

以萜烯树脂和邻苯二酚为原料,合成了萜烯-邻苯二酚树脂.采用柱层析法分离萜烯树脂和萜烯-邻苯二酚树脂,分别采用中性氧化铝和强碱性阴离子交换树脂作固定相,汽油、乙醇、NaOH-乙醇溶液作洗脱剂对萜烯树脂和萜烯-邻苯二酚树脂进行分离提纯.通过对洗脱液进行紫外光谱分析,表明用中性氧化铝作固定相,分别用汽油、乙醇和NaOH-乙醇溶液洗脱,能较好地分离萜烯树脂和萜烯-邻苯二酚树脂.     

色谱法测定制浆造纸工业漂白废液中的草酸浓度

近年来草酸钙(草酸垢)的形成在制浆造纸工业中造成诸多问题,因此如何分析及控制漂白废液中的草酸浓度就显得尤为重要.高效液相色谱和离子交换色谱等色谱法一般可以作为测定草酸的标准方法.本研究以一个基于阴离子交换柱的离子交换色谱法作为对照方法,利用一套配备了Aminex HPX-87H液相色谱柱的高效液相色谱系统测定漂白废液中的草酸浓度.结果显示,漂白废液中含有一些干扰高效液相色谱法测定的化合物.通过采用稀释样品后再经活性炭吸附的处理方法,可以得到较为满意的结果.分析发现高效液相色谱法与离子交换色谱(对照法)之间的相关性较好,相关系数为0.994.该方法的建立将有利于监控制浆造纸企业中闭路循环漂液中形成草酸钙时的临界草酸浓度.     

聚合松香中二聚体含量的GC法测定

本文报导了聚合松香中二聚体含量的GC法测定。样品用四氢呋喃溶解,加6％(CH_3)_4NOH使样品中树脂酸完全酯化,酯化液在色谱注射口内温度下转化为甲酯并气化,以高纯氮为载气,进入色谱柱完全分离,通过Pye104GC的FID进行测定,用面积归一化法计算含量。本法定量准确,误差小于2％,分析一个样品需24分钟。     

固相萃取净化-高效液相色谱法测定果汁中纽甜的含量

建立了固相萃取净化高效液相色谱法测定果汁中纽甜的含量的实验方法。色谱柱采用Waters C18柱(250mm×4.6mm,5μm),以乙腈-离子对缓冲溶液梯度洗脱,采用二极管阵列检测器测定果汁中纽甜的含量。其中标准物质的线性范围分别为5~100μg/mL,检出限为0.1μg/mL,加标回收率为98.4%~105.1%,相对标准偏差0.64%(n=6)。结果表明:该方法适用于果汁中纽甜的定量分析。     

高速逆流色谱分离制备胡椒中的胡椒碱

利用高速逆流色谱从胡椒粗提物中分离制备其主要成分胡椒碱,两相溶剂系统为石油醚-乙酸乙酯-甲醇-水(体积比1:0.8:0:0.8),上相为固定相,下相为流动相.从300 g的粗提物中经过一次分离得到纯度为99.1％的胡椒碱65.2 mg,其化学结构由EI-MS、1H NMR和13CNMR鉴定.     

中心复合设计法优化熊果酸和齐墩果酸的HPLC测试条件

在考察HPLC流动相体系和色谱柱对熊果酸、齐墩果酸分离测定影响的基础上,采用中心复合设计,以分离度和分析时间为响应值,对熊果酸和齐墩果酸HPLC分离测定的主要影响因素(甲醇与水相的体积比、水相中磷酸的体积分数、流动相流速及柱温)进行多重响应优化,建立了有效、快速的分离测定熊果酸和齐墩果酸的HPLC方法。结果表明,在210 nm的检测波长下,用Shim-pack ODS-CLC(M)色谱柱,流动相为甲醇/磷酸水溶液体系,甲醇与水体积比为91.7∶8.3,磷酸体积分数为0.05%,流速为0.6 mL/min,柱温为21℃,齐墩果酸和熊果酸可以在23 min内得到有效分离,分离度达到1.739。     

毛细管柱气相色谱法同时检测10种常用有机磷农药

报道了用大孔径毛细管柱代替填充柱分离１０种常用有机磷农药的气相色谱条件的选择，并找出了较佳的气相色谱条件。     

Decontamination of synthetic solutions containing heavy metals using chemically modified sawdusts bearing polyacrylic acid chains

New materials containing carboxylate groups have been synthesized by grafting polyacrylic acid onto sawdust. These new adsorbents were subjected to continuous extraction of different metal ions using packed columns to determine their maximum binding capacities. They exhibit binding capacities 15–40 times higher than unmodified sawdusts for removal of Cu²⁺, Ni²⁺, and Cd²⁺ chosen as representative heavy metal ions. Cation desorption and adsorbent regeneration could be effected by elution with a diluted HCl solution; water as an eluent has no effect on metal desorption.     

Flash chromatography on cartridges for the separation of plant extracts: Rules for the selection of chromatographic conditions and comparison with medium pressure liquid chromatography

Empirical rules for the selection of chromatographic conditions on flash chromatography cartridges were developed, with an emphasis on gradient mode. These rules were then tested with separation of extracts from important medicinal plants including Curcuma xanthorrhiza, Piper nigrum and Salvia milthiorrhiza. Sepacore® cartridges enabled a good separation of compounds with a broad range of polarity, as typically found in plant extracts. The chromatographic resolution remained, however, lower than that achieved on classical columns packed with material of smaller particle size. For poorly soluble extracts, solid introduction gave better results than liquid injection.     

胶合空心木柱结构设计与制造工艺

胶合木结构建筑中,柱作为轴心受压构件,需要对其承载能力进行强度和稳定性验算。对空心柱进行理论设计计算,从而确定一定尺寸、规格下柱能承受的最大载荷。由于没有专用设备进行实验论证,本研究仅对不同规格的空心木柱和实心木柱进行对比,得出了在保证空心木柱强度与实心木柱相当时,空心木柱的外围直径与实心木柱相比均有一定程度扩大的结论,从而使胶合木结构中的胶合木柱达到了美观与结构的双向要求。同时提供了几种具体空心木柱的外观设计。     

仙人掌超氧化物歧化酶提取与纯化工艺研究

为了实现对仙人掌资源的深度开发利用,试验研究了以规模化种植的食用仙人掌为材料,提取和纯化SOD的工艺路线和相关参数。去除新鲜仙人掌表面的刺和蜡质、清洗、榨汁、粗滤、超声波处理、离心,得仙人掌粗酶液,再经热处理、硫酸铵盐析和SephadexG-100柱层析分离纯化,高分子聚合物脱水,真空冷冻干燥,获得仙人掌SOD粗酶粉,得率为13.3mg/100g.fw,酶活力为860U/mg。超声波处理能够显著降低仙人掌原浆的黏稠度,提高出汁率,相应提高从原浆里提取SOD的得率。通过正交试验,超声波功率600W、温度40℃与时间20min的组合,所得仙人掌汁液SOD活力收率最高,达215.6U/mL。硫酸铵饱和度40%和85%分别用于除杂质和沉淀SOD目标蛋白具有纯化和浓缩的双重效果。     

二氧化硅凝胶葡萄糖传感器上羟甲基纤维素酶活性测定

提出了用SiO2凝胶包埋葡萄糖氧化酶(GOD)电化学传感器(GOD/SiO2)测定羟甲基纤维素酶(CMCE)活性的方法,即基于电极对纤维素水解后生成葡萄糖的催化氧化.考察了各种实验条件对CMCE酶活性测定的影响.实验表明,GOD/SiO2电极检测电位为 0.57 V(以饱和甘汞电极为参比电极), 稳态响应电流与纤维素酶活性在5～400 U/L 之间有线性关系,该方法可用于微量羟甲基酶活性测定.     

灵芝多糖体的提取及其理化性质的研究

灵芝是一种木材腐朽菌,具有良好的药用价值,在中国和其它一些国家享有盛誉。作者对赤(灵)芝(Ganoderma lucidum)子实体多糖的提取及其理化性质进行了研究。结果表明,粗多糖得率为1.38％,纯化后的糖经薄层色谱和气相色谱分析查明含有木糖、甘露糖、阿拉伯糖、半乳糖和葡萄糖,糖基比依次为1:1:1.7:5:20。用凝胶过滤得分于量约为23000和34000。经红外光谱测定该多糖在1050、1140、1420和3400cm~(-1)处均有明显的吸收峰。本文提出了一个从灵芝子实体分离和纯化多糖体的方法。     

Bending resistance of repaired column members and shear resistance of opening frames with repaired columns of conventional Japanese wooden houses

When it is necessary to repair conventional Japanese wooden houses, the decayed lower parts of columns should be replaced with new wood material. The bending resistance of columns repaired by four methods and the shear resistance of opening frames with those repaired columns were investigated in this study. Bending tests of the repaired columns showed differences in initial bending stiffness and maximum bending moment related to the repair methods and loading direction. Racking tests were conducted on door opening frames with conventional door head members or upper partial walls sheathed with 12-mmthick plywood. The conventional frame specimens broke at door head-column joints with no obvious bending deformation of the columns, resulting in little difference in load-shear deformation curves among the repair methods. The columns of plywood-sheathed specimens, on the other hand, clearly were bent after the nails at the plywood-to-wood frame joints started to pull off. The load-shear deformation curves of the plywood-sheathed specimens did not vary regardless of the repair methods when shear deformations were small but were affected by repair methods as shear deformation increased.     

用生物活性炭法去除饮用水中氯仿的试验研究

本文简述了饮用水中三卤甲烷类特别是氯仿的米源和危害;阐述了粒状活性炭过滤吸附和臭氧化—粒状活性炭过滤吸附两种流程的生物活性炭法去除氯仿的效能与机理。试验发现,各活性炭柱在运行初期,均有较高的去除率,其中北京X—11型炭的吸附性能高于太原ZJ—15型炭,并从Lundelius规则和炭层中的生物活性的角度进行了解释。活性炭流程的出水氯仿穿透点为4000～5000床体积;臭氧—活性炭流程为12000～15000床体积。并对臭氧活性炭流程除氯仿效能较好的原因进行了探讨。两种流程的炭柱出水中氯仿比原水中的氯仿浓度高。作者认为这是炭层中的微生物在厌氧条件下将有机物先降解为各种羧酸最后降解为甲烷,而甲烷与水中的游离氯发生自由基取代反应形成氯仿所致。     

Effects of plant growth regulators,carbon sources and pH values on callus induction in Aquilaria malaccensis leaf explants and characteristics of the resultant calli

The endangered tropical tree, Aquilaria malaccensis, produces agarwood for use in fragrance and medicines. Efforts are currently underway to produce valuable agarwood compoundsn tissue culture. The purpose of this study was to develop an optimal growth medium, specifically, the best hormone combination for callus suspension culture. Using nursery-grown A. malaccensis, sterilized leaf explants were first incubated on basic Murashige and Skoog(MS) gel medium containing 15g/L sucrose and at pH 5.7. Different auxin types including 1-naphthaleneacetic acid(NAA), 2,4-dichlorophenoxyacetic acid(2,4-D), and indole-3-butyric acid(IBA), were tested at various concentrations(0.55, 1.1 and 1.65 μM) using the basic medium. Leaf explants were incubated for 30 days in the dark. Callus induced by 1.1 μM NAA had the highest biomass dry weight(DW) of 17.3 mg; however the callus was of a compact type. This auxin concentration was then combined with either 6-benzylaminopurine(BAP) or kinetin at 0.55, 1.1, 2.2 or 3.3 μM to induce growth of friable callus. The 1.1μM NAA + 2.2μM BAP combination produced friable callus with the highest biomass(93.3mg DW). When testing the different carbon sources and pHs, sucrose at 15g/L and pH at 5.7 yielded highest biomasses at 87.7mg and 83 mg DW, respectively. Microscopic observations revealed the arrangement of the friable cells as loosely packed with relatively large cells, while for the compact callus, the cells were small and densely packed. We concluded that MS medium containing 15 g/L sucrose, 1.1 μM NAA + 2.2 μM BAP hormone combination, and a pH of 5.7 was highly effective for inducing friable callus from leaf explants of A. malaccensis for the purpose of establishing cell suspension culture.