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1.
In this study, the tetramido macrocyclic iron complex (Fe-TAML) was successfully synthesized, and then it was characterized using 1H nuclear magnetic resonance (1H NMR), electrospray ionization mass spectrometry (EIS-MS) and elemental analysis. An activated peroxide system was established for low-temperature bleaching of cotton by combining the synthesized catalyst (Fe-TAML) with hydrogen peroxide. Experimental results showed that the Fe-TAML/H2O2 bleaching system exhibited effective bleaching performance in the use of 2 μM Fe-TAML, 20 g/l H2O2, 1 g/l NaHCO3, 2 g/l scouring agent and 2 g/l wetting agent at 60 °C for 60 min. In comparison with the conventional bleaching system, the Fe-TAML/H2O2 system provided bleached cotton with a superior degree of whiteness, higher tensile strength and acceptable water absorbency. The application of Fe-TAML was expanded and the activated peroxide system may provide a green approach for the cotton bleaching.  相似文献   

2.
Rats fed a diet containing a highly purified preparation of phaseolin, the main globulin from the seeds of Phaseolus vulgaris, rapidly lost weight. Fecal nitrogen outputs were elevated and the N digestibility, based on conventional method estimation, was only 37.5%. By using immunological techniques, however, it was shown that the bulk of the nitrogen recovered in the feces was not chemically related to phaseolin. After correction for this non-phaseolin N, the true digestibility of phaseolin was estimated to be 74.3%. It is suggested that phaseolin and/or undigested fragments derived from the native molecule may, as reported for the lectins, stimulate the secretion of endogenous N, possibly mucins.  相似文献   

3.
This study reports the dual-functions of ferrous sulfate, i.e. as a carbon-yield-enhancer and as a pore-size-controller, in the preparation of porous carbons from rice straws. Through the impregnation of rice straws with 0.5 M aq. FeSO4, the carbon yield of the resultant porous carbons increased by ca. 10% and the size of the newly created pores was precisely controlled at the diameter of 0.53 nm during carbonization process. The observed results were discussed from the view points of the thermal degradation mechanism of cellulose and the pillar effects by the in-situ formed crystallites of Fe3O4. The inherent magnetic property due to the presence of magnetite, Fe3O4, was an additional merit of the obtained porous carbons.  相似文献   

4.
花生花芽分化的形态解剖学研究   总被引:2,自引:0,他引:2  
试验依据花生花器官形及雌雄配子体的发育顺序,将花芽分过程划为10个时期,即①花芽原基期;②二叉苞片原基期;③花萼原基期;④雌雄蕊原期;⑤花冠原基期;⑥小孢子母细胞期;⑦小孢子四分体期;⑧单核花粉粒期;⑨二核花粉粒期;⑩花粉粒成熟期。研究发现花生成熟种子胚芽具有7个花序原基,雌雄配子体形成时间不同步。  相似文献   

5.
通过探究棉花柱头外露性状的成因,为棉花柱头外露种质在杂交制种方面的利用提供理论指导。以陆地棉遗传标准系TM-1和染色体代换系CSB-18为试验材料,研究2种材料在不同发育阶段苞叶、花瓣、柱头的生长情况差异和结铃率差异。结果表明:在整个生长发育阶段,CSB-18和TM-1相比,苞叶大小和柱头长短没有明显差异,但CSB-18花瓣明显短于TM-1花瓣。CSB-18柱头外露与柱头长短无关,是该材料花瓣较短导致。CSB-18结铃率明显低于TM-1结铃率。  相似文献   

6.
以海南山苦茶叶为原料,采用电感耦合等离子原子发射光谱法对不同产地山苦茶叶元素含量进行比较,并对万宁产山苦茶叶、茶渣及其经热水浸提后乙醇沉淀法分离的水溶性粗多糖中的14种矿物质元素含量进行了分析。结果表明:山苦茶叶水溶性粗多糖得率为16.7%,山苦茶叶中14种元素含量由高到低顺序依次为常量元素钾、钙、镁、钠、硫、磷和微量元素钡、锰、铁、锌、铜、铬、钼、铍。不同地区的山苦茶叶各元素含量稍有不同,总体差异不大。对茶渣和粗多糖的各元素含量及其形态分布分析发现,山苦茶各元素(除钾外)的不溶态(36.9%~94.2%  相似文献   

7.
Processing of images captured by a digital camera showed to be useful in studying the microstructure (porosity characteristics and fractal dimension) of leavened baked products. Five different samples were baked including a control and 4 other samples in which wheat flour was partially replaced with other plant flours. Pasting temperature (°C) ranged from 72.94 to 76.25 with chickpea flour showing the highest value. The sample containing amaranth flour presented high porosity (8.23%) with high number of large pores. Whereas, the number of pores was highest for teff flour with 209 pores. This is an indication of weak potential of amaranth flour in stabilizing gas cells. The fractal dimension ranged from 1.644 to 1.683, where amaranth flour showed the lowest fractal dimension. The pore characteristics evaluation, pore size distribution, number of pores, mean area and largest area of pores were influenced when gluten was reduced. Processed images proved that coalescence can be a cause of large pore development when gluten is partially removed.  相似文献   

8.
为了进一步探讨安化云台山茶树种质资源的遗传多样性和茶类适制性,采用实地观测和光学显微镜观察的方法,以槠叶齐为对照,对安化云台山30个茶树单株展开研究。结果表明,其叶面积16.99~53.49 cm2,大叶占70%,叶片多为椭圆形,微隆起,叶缘平展,叶尖骤尖;栅栏组织1~2层,平均厚度73μm,海绵组织平均厚度142μm,栅栏组织与海绵组织比在0.6以上的有10株;运用正态分布,叶片厚度主要集中在241~285μm之间。  相似文献   

9.
10.
A relatively new, unique column packing material for reversed-phase high-performance liquid chromatography (RP-HPLC) was evaluated for rapid separation of wheat glutenin protein subunits. The product named “Poroshell” by the manufacturer consists of a solid core and a porous coat instead of solid silica spheres used in conventional RP-HPLC column packing. This architecture favours rapid mass transfer, facilitating faster reversed-phase separations of biomolecules compared to conventional silica columns. The main objective of this study was to evaluate the quality of separations of glutenin subunits (GS), as well as to optimize conditions to produce the fastest possible run times without sacrificing resolution using a Poroshell 300SB-C8 2.1×75 mm column. The stability of GS separations over time was also assessed. Two different bread wheat genotypes were used for optimization of separation conditions and six more common and durum wheat genotypes possessing different subunit combinations were used for further evaluation. Glutenin protein was extracted with 0.08 M Tris–HCl buffer (pH 7.5) containing 50% 1-propanol under reducing conditions after pre-extraction of soluble proteins with 50% 1-propanol. Optimization of GS resolution and sample throughput by RP-HPLC was assessed in response to variation in eluent flow rate, acetonitrile (ACN) gradient, and column temperature. The best resolution of both HMW- and LMW-GS was obtained in 13 min using a 23–44% ACN gradient with a flow rate of 0.7 mL/min at 65 °C. Subunit elution times and integrated areas were highly repeatable even after several hundred injections. Highly satisfactory separation of HMW-GS and quantification of ratio of HMW- to LMW-GS were achieved in less than 4 min per sample using a modified HPLC gradient. Ratio of HMW- to LMW-GS was unaffected by the speed of the separations. As well, the elution order of HMW- and LMW-GS was unaffected by the rapid analysis, compared to conventional RP-HPLC separations, so no new learning was required for interpreting chromatograms and classification of subunits. The rapid RP-HPLC method using the Poroshell column appears to be very well suited for routine quantification of HMW-GS and LMW-GS especially for purposes of wheat quality screening and wheat cultivar development activities where large numbers of samples are typically encountered.  相似文献   

11.
稻叶形态是水稻株型改良的重点,本文介绍了叶形和叶色在遗传和分子生物学等方面的研究进展,并对水稻叶片形态的应用前景进行了展望。  相似文献   

12.
披碱草(Elymus rectisctus,以下简写为E.rectiselus)具有二倍性无融合生殖特性,为了获得小麦-E.rectisetus稳定的异附加系或异代换系,对(小麦-E.rectiselus)BC2F2衍生后代的细胞学和形态学进行了研究。结果表明,在BC2F5~BC2F7镜栓的单株中,体细胞染色体数目在22~50条之间,其中42条和44条染色体所占的比例最大,分别占鉴定植株总数的38.0%和35.9%。三个2n=42=21″的稳定株系与普通小麦Fukuhokomugi杂交F1的花粉母细胞染色体构型为2n=18″ 6′,表明有三对E.rectiselus染色体代换到普通小麦中;三个2n=44=22″的稳定株系与Fukuhokomugi杂交F1的花粉母细胞染色体构型为21″ 1′,表明它们为二体异附加系。此外,衍生后代的形态学特征趋向于普通小麦。  相似文献   

13.
A heuristic-based simulated annealing has been developed to optimize the operation of a multiple reservoir system. Simulated annealing is a probabilistic search algorithm, motivated by an analogy of physical annealing in solids. It has been increasingly applied to a broad spectrum of fields for which little prior knowledge is required. The developed model is illustrated by a test application to a benchmark problem of a 10-reservoir problem that had been solved previously in the literature. For this problem, simulated annealing shows its ability to provide better result than those obtained from other techniques. The model is then applied to the real multiple reservoir system in Thailand to derive optimal operating policies. The objective function is formulated to minimize the irrigation deficits during 3 years. The performance of the simulated annealing is compared with that of the genetic algorithm developed for the same problem. The results show that the simulated annealing is more efficient than the genetic algorithm. Simulated annealing produces higher quality solutions while spending lesser computation time compared with the genetic algorithm. The results obtained from these applications have proved that the simulated annealing is capable of addressing a large and complex problem. Simulated annealing is quite a new promising search algorithm for reservoir optimization problems. It is worthy of further investigation for other applications in this area of research.  相似文献   

14.
Abstract The diversity, abundance, spatial distribution, and phenology of the mygalomorph spider community in the "Ernesto Tornquist" Strict Nature Reserve were analyzed in this study. Located in southwestern Buenos Aires, Argentina, the Reserve is representative of the Ventania system, which is a sigmoidal mountain belt 180 km in length. This exceptional hilly ecosystem is home for many endemic species and rich native fauna and flora. Spider abundance was sampled monthly from October 2009 to October 2010 by hand capture and pitfall traps on grassland slopes. The species recorded in the study area were: Actinopus sp.1 (Actinopodidae); Grammostola vachoni and Plesiopelma longisternale (Theraphosidae); Acanthogonatus centralis (Nemesiidae); and Mecicobothrium thorelli (Mecicobothriidae). Grammostola vachoni and Acanthogonatus centralis were the dominant species in hand capture and pitfall traps, respectively. The seasonal variation, diversity, and abundance of the mygalomorph community are analyzed and discussed here. The Mygalomorphae of the Ventania system comprises an important group of sedentary and cryptozoic spiders that seem to be highly dependent on habitat type and environmental factors.  相似文献   

15.
将50只KM雄性小鼠按每组10只随机分为正常组、谷氨酰胺组及L-茶氨酸低、中、高剂量组,连续灌喂28 d,探究L-茶氨酸对小鼠肠道形态结构及游离氨基酸的影响。结果表明,与正常组相比,小鼠肠道绒毛高度随L-茶氨酸剂量的增大而增加,各剂量组的十二指肠绒毛高度和中、高剂量组的空肠绒毛高度及其绒毛高度与隐窝深度的比值均达显著水平(P<0.05),血清游离氨基酸含量及中、高剂量组的尿素氮含量显著降低(P<0.05),高剂量组的碱性磷酸酶、总蛋白含量显著升高(P<0.05);L-茶氨酸对不同肠道游离氨基酸含量的影响随剂量的增大而升高,其中,十二指肠中的各茶氨酸剂量组的全部必需氨基酸和大部分非必需氨基酸显著升高(P<0.05),且高剂量组的必需氨基酸含量显著高于低剂量组(P<0.05);空肠中的低剂量组的必需氨基酸Thr、Lys、Ile及中、高剂量组的全部必需氨基酸含量显著升高,且中、高剂量组中除Cit外的其他氨基酸含量均显著高于低剂量组(P<0.05);回肠中的低、中、高剂量组的全部必需氨基酸及大部分非必需氨基酸含量显著降低,且中、高剂量组中除GABA外的其他氨基酸含量显著高于低剂量组(P<0.05)。结果表明,L-茶氨酸可通过增加肠道绒毛高度、提高绒毛高度与隐窝深度比值来改善小鼠肠道形态结构,同时可促进十二指肠、空肠对氨基酸的吸收利用。  相似文献   

16.
氮素供应形态对水稻根系形态和磷吸收的影响   总被引:5,自引:1,他引:5  
 采用水培方法,研究了缺磷条件下不同形态氮(NH4+、NO3-和NH4NO3)下的水稻根系形态性状,以及它们产生的后效应对磷吸收的影响。结果表明,在氮素供应充足但磷饥饿胁迫的状况下,氮素形态对根系的影响仍然十分显著。与单一的铵营养相比,铵硝混合营养增加了根长和根系的表面积、根系的密度以及磷的总吸收量;与单一的铵或硝营养相比,铵硝混合营养可增加吸收的磷从根系向地上部的运输。因此,铵硝混合营养改善低磷胁迫下水稻对磷的吸收和转运,其部分原因与氮素形态与根系形态发生有关。  相似文献   

17.
Zucchini, Cucurbita pepo L., is often colonized by economically important insect pests such as the striped (Acalymma vittatum Fab.) and spotted (Diabrotica undecimpunctata howardi Barber) cucumber beetles. To evaluate the impact of an interplanted cover crop on arthropods associated with zucchini, field experiments were conducted in which sunn hemp (Crotalaria juncea L.) was interplanted with zucchini as a living mulch and compared with zucchini monoculture (bare-ground) during 2009, 2010 and 2011 growing seasons. The experiment consisted also of two types of fertilizer usage including the application of synthetic or organic fertilizer in the form of chicken manure. Foliar counts of arthropods conducted on zucchini plants showed significantly lower numbers of the striped cucumber beetle in sunn hemp interplanted plots compared to bare-ground treatment plots. Also, fewer spotted cucumber beetles were found on zucchini plants in sunn hemp plots. Aphid abundances were variable during the study and significantly lower in sunn hemp treatment plots at one study site in 2009. Among predators, spiders were significantly more abundant in sunn hemp treatment plots during 2009. Fertilizer type did not have a significant effect on arthropod numbers on zucchini plants. Potential causes of arthropod population differences among the two treatments are discussed.  相似文献   

18.
籼粳亚种间杂种不育性的形态与研究进展   总被引:1,自引:0,他引:1  
对籼粳亚种间杂种不育性的细胞形态观察,籼粳亚种间杂种结实的亲和性及籼粳亚种间分化与亲和性的关系研究进行综述,并对研究中存在的问题和发展向进行了初步探讨。  相似文献   

19.
On-farm trials were conducted to evaluate the potential of the System of Rice Intensification (SRI), a low-input crop management system, to increase rice yields and reduce water consumption on subsistence farms in several regions of Panama and to determine how inherent soil fertility might affect SRI yields and the yield response to SRI management in the first season of SRI management. SRI practices increased yield by 47% on average and showed potential to increase yield by over 90%, while reducing water consumption by as much as 86%. SRI yields were correlated with available soil K and the difference between SRI and the conventional system yields was positively correlated with extractable Ca, Mg and Mn. The results of this study indicate that SRI is a promising rice production system for smallholder farmers in rural Panama farming under Panamanian soil conditions.  相似文献   

20.
Due to global warming, water is expected to become scarce especially in semiarid regions. Therefore, there is a need to increase the efficiency in water use by crops under rainfed agriculture. The effect of nutrient availability on the growth, production, root development, water relations and water use efficiency (WUE) by the intercrop maize/cowpea was investigated in 2 contrasting years (dry and wet) in the semiarid region of Brazil. The crops were grown on a strongly acidic, sandy soil with three treatments: (i) application of NPK fertilizers plus lime (NPK + lime), (ii) application of NPK fertilizers (NPK) and (ii) control (Contr.) in low and high input regimes. The soil water balance was calculated with the crop model EPICSEAR. Application of fertilizers and lime increased biomass production and grain yield of the intercrop up to 400% and 550%, respectively, and maize suffered more from the effects of low nutrient availability and soil acidity than cowpea. The root development of both crops was strongly improved by the application of NPK and lime and cowpea developed a deeper root system which enabled this crop to keep a higher transpiration rate in the dry year. As a consequence of the shallow root system, maize was prone to water stresses caused by the dry spells and its harvest index was reduced when dry spells occurred during flowering and grain filling.  相似文献   

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