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51.
压砂砾石水-岩作用下元素释放规律 总被引:1,自引:0,他引:1
为了解压砂砾石在干湿交替和冻融循环这两种水-岩作用过程中的元素释放规律,以宁夏中卫地区一种主要压砂砾石为研究对象,对该种压砂砾石本身元素组成及其干湿交替和冻融循环模拟试验条件下元素累积过程做了检测分析.发现绿色板岩压砂砾石共由O,Si,Fe等25种元素组成,其中包含了多种植物生长所需要且能溶于水的矿质元素.这种压砂砾石在干湿交替和冻融循环处理过程中能够释放N,Ca,K等多种植物生长所需要的大量元素、微量元素和有益元素,50次干湿交替和冻融循环处理条件下,各类元素累积释放量分别为786.90,958.18 mg.明确了宁夏中卫地区一种主要压砂砾石的元素组成,摸清了干湿交替和冻融循环过程中压砂砾石成矿元素的释放规律,对维护当地土壤健康、提高农作物品质具有重要意义. 相似文献
52.
以壳寡糖(COS)为试验材料,采用TEMPO氧化法将壳寡糖C6位上的羟甲基直接氧化成为羧基,制备6-羧基壳寡糖(CCOS)。以Ca Cl2作为钙源,通过探讨体系pH值、反应温度、反应时间、CCOS与Ca Cl2质量比对CCOS-Ca(Ⅱ)得率的影响,采用三因素五水平中心旋转组合设计优化了制备工艺。并对产物进行傅里叶变换红外光谱扫描及元素分析。使用Design-Expert软件对响应面试验数据进行回归分析。所得CCOS-Ca(Ⅱ)制备最佳工艺参数为:反应pH值为8.3,反应时间60 min,反应温度50℃,CCOS与Ca Cl2质量比为34。在此优化工艺条件下,验证试验螯合率为88.86%。通过红外光谱及元素分析,证明了钙螯合物的形成,CCOS-Ca(Ⅱ)配合物的结构初步认为CCOS与Ca2+摩尔比为2∶1。CCOS分子除了含有—OH、—NH2外,还含有—COOH,能够对钙进行有效螯合,体系pH值、反应温度、配体质量比对螯合结果影响显著,所得CCOS-Ca(Ⅱ)络合物不仅能发挥壳寡糖本身独特的生物活性,而且有可能起到协同效应,增强各自的生物活性。 相似文献
53.
Pecan [Carya illinoinensis (Wang.) C. Koch.] trees were given four treatments: (i) control (no zinc application) (ii) DeltAg Zinc Plus® applied in fall, at budbreak, and after pollination (iii) DeltAg Zinc Plus applied in fall only and (iv) zinc sulfate 36.6% applied at budbreak, 3 weeks later, and after pollination. Leaf elemental concentration of zinc (Zn) increased with all zinc treatments in year one. In year two, the three applications of Zinc Plus produced the highest leaf elemental concentrations of Zn. The zinc sulfate treatment had a positive effect on nut and kernel weight in both years while the other two Zn treatments had effects that varied across years. Zinc sulfate had yields at least as good and nut quality at least as good as the other Zn treatments. Given that Zinc sulfate is the lowest-cost Zn treatment, the results reported here favor using zinc sulfate. 相似文献
54.
Olga Bezuglova 《植物养料与土壤学杂志》2019,182(4):676-682
The molecular structure of humus acids remains one of the most challenging issues in the soil science. The focus of the current research lies in defining the molecular and supramolecular structure of soil humus acids. This paper provides a brief review of the current understanding of the problem and shares findings of the elemental and X‐ray structural analysis of humic and fulvic acids extracted from Chernozems and Chestnut soils in the Rostov region. This region occupies a large area of the South‐European Russia. Humic acids in the studied soils have reduced carbon content compared to average parameters for these soil types. The supramolecular organization of humic acids in three‐dimensional space contains two to four layers of condensed aromatic systems supplemented by a network of chain fragments of different regularity and length. Parameters of this structure vary for soils of different genesis and genetic horizons. However, interplanar distances are fixed in the range of 0.349 to 0.371 nm. Thickness of the carbon network band increases with the benzoidicity level of humic acids. The obtained results confirm the specific matrix structure of humic acid molecules. Considering currently available scarce data these findings are valuable and unique. Our findings are consistent with the general hypothesis about the supramolecular nature of humic substances. 相似文献
55.
分别用焦磷酸钠和氢氧化钠浸提新鲜牛粪、蜉金龟堆肥(APCM)和自然堆肥(腐熟牛粪)产物中的类富里酸,采用元素分析、红外光谱及差热分析研究其结构特征.元素分析结果表明,自然堆肥焦磷酸钠浸提物类富里酸(NaFLA)的芳香性、碳水化合物及含氮化合物的含量均高于新鲜牛粪和蜉金龟堆肥.新鲜牛粪氢氧化钠浸提物类富里酸(PAFLA)的芳香性、碳水化合物均高于自然堆肥和蜉金龟堆肥;而自然堆肥PAFLA的含氮化合物含量高于新鲜牛粪.红外光谱分析表明蜉金龟堆肥NaFLA的羧酸脂类化合物及酮类化合物有所增加;自然堆肥和蜉金龟堆肥PAFLA的氢键强度、芳化度高于新鲜牛粪PAFLA.差热分析结果表明,与新鲜牛粪和自然堆肥相比,蜉金龟堆肥NaFLA分子中脂族化合物分解及外围官能团的脱羧和彻底氧化,分子内部芳香结构分解.与新鲜牛粪PAFLA相比,蜉金龟堆肥及自然堆肥PAFLA的脂族性较强,芳香性较弱. 相似文献
56.
57.
By the definition and interpretation of directional elemental pixel sets, a method for getting the directional image from the binary fingerprint image using the statistic characteristics of DEPS is presented in this paper. This method is better than traditional methods in processing speed, computing complexity and resisting noises. The directional image got by this method is used to the matching of ridges frame in a fingerprint verification system, and the testing result shows that the method is effective. 相似文献
58.
采用盆栽试验,研究施用动物粪便、动物残体、草本残体、木本残体5年后对黑土胡敏酸(HA)、富里酸(FA)和胡敏素(HM)元素组成的影响。结果表明:与CK相比,有机物料施用5年后,黑土HA的C、H含量均显著降低,而缩合度及含氮基团数量提高,并以木本残体作用最显著。除动物粪便处理HA的N含量与CK的大致相同外,其余有机处理N含量均显著提高,各处理HA的O含量由大到小依次为木本残体〉草本残体〉动物粪便〉CK〉动物残体,且各处理差异显著。有机物料的施用可以降低FA的缩合度,并以草本残体作用最显著,同时草本残体施用提高了FA的N含量。而动物残体使FA的H含量显著降低。有机物料FA的C含量表现为草本残体〉木本残体〉CK〉动物残体〉动物粪便,而O含量及氧化度由大到小依次为动物残体〉动物粪便〉CK〉木本残体〉草本残体,且各处理间差异显著。有机物料的施用使HMi的C、H含量下降而使O含量上升,并以草本处理作用最显著,同时草本处理也使HMi的N含量降低。施用有机物料使HMc的氧化度、芳香度提高,结构变复杂。 相似文献
59.
《Communications in Soil Science and Plant Analysis》2012,43(15-16):2101-2111
Abstract Fulvic acids (FAs) are an important dynamic component of soils that may be affected by soil management. Carbon‐13 cross‐polarization total sideband suppression nuclear magnetic resonance (CP‐TOSS 13C NMR) was used to examine the effect of cover crop systems on the characteristics of fulvic acid fractions. FA was isolated from soils with the following treatments: 1) vetch/rye, 2) rye alone, and 3) check (no cover crops) with varying nitrogen fertilizers. Preliminary NMR results indicate that FA from the rye alone system both with and without nitrogen fertilizers contains less aliphatic carbon (0–108 ppm) than that from the other two treatments. Based on the elemental composition analysis result, C∶N ratio of FA from rye alone cover with or without nitrogen fertilizer is lower than FA from vetch/rye cover system. These data suggest that farming systems affect the FA compositions. 相似文献
60.
《Communications in Soil Science and Plant Analysis》2012,43(4):249-258
Abstract The analysis of plant tissue, generally leaves, is considered to be an important step in diagnosing and confirming a mineral element deficiency. The mineral element status of the plant can be accurately measured by the analysis of plant tissue if the tissue is properly sampled. Tissue analysis is often the best indication for recommending fertilizer or supporting nutrient spray treatments. The development of a relatively fast and accurate method of analyzing plant tissue has been made possible with the advent of atomic absorption spectroscopic techniques. 相似文献