山西风化煤腐植酸活化研究

风化煤中腐植酸多被钙离子、镁离子固定,具有生物活性的水溶性腐植酸含量甚微。因此,在生产腐植酸肥料时,有必要进行活化处理。以山西某地风化煤为原料,研究活化剂种类、添加量,加水量,活化温度,反应时间对水溶性腐植酸含量的影响。结果表明,最佳活化条件为:以质量比为2的Na_2CO_3和NaOH混合物为活化剂,活化剂占风化煤质量的12%,加水量占风化煤质量的40%,温度75℃,时间2 h,此条件下水溶性腐植酸质量分数可接近40%。     

活化腐植酸制备有机-无机复混肥的工艺研究

风化煤、褐煤等物质中含有大量的腐植酸,但在自然界中多数被钙、镁离子固定,能被作物直接吸收利用的水溶性腐植酸普遍含量甚微。因此,生产腐植酸肥料时,有必要进行腐植酸活化处理。本文研究了碳铵与氨水联合对褐煤进行活化处理,得到了生物活性较高的腐植酸铵,并以腐植酸铵作为有机原料与无机养分复混造粒制备了25-5-10有机-无机复混肥样品,经过性能指标和外观效果等方面的评价,明显优于未经活化的褐煤制得的样品。     

风化煤的微生物转化:Ⅲ.预处理对其影响(续完)

风化煤中腐植酸为大分子物质，并处于结合状态，微生物很难利用，本研究利用不同功率的起声波(200W、400W、600W、800W、1000W)、不同处理时间(200W，2min、5min、10min、15min)和化学方法(NH4HCO35．0g，7．5g，10．0g，(NH4)2HPO40．5g，1．0g，2.5g)对风化煤进行预处理，发现风化煤的水溶性大幅度提高，特别是化学处理。微生物更容易利用，培养7d很大一部分校分解掉或转化为微生物生物量。紫外吸收光谱的结果表明，起声波和化学预处理并不影响风化煤中物质的分子结构，但是，经过微生物处理后，分子结构发生了改变。     

风化煤的微生物转化：I菌种筛选及转化能力测定

腐植酸是风化煤的主要成分，一般水溶性和生理活性很低，直接应用效果很差，通过微生物处理有望提高其活性，开发风化煤应用新技术。本研究从土壤、根际、枯枝落叶、风化煤等多种生境中筛选到能利用风化煤或腐植酸的69个菌种，但仅有6个菌株能液化风化煤，出现小液珠或使培养基染成黄褐色至黑色。液体培养条件下，风化煤失重率达到47．69％（山西风化煤）和39．54％（内蒙古风化煤），紫外和红外光谱分析表明风化煤经微生物作用后，不仅腐蚀植酸被溶解出来，同时被分解，分子中－OH增加、C＝O基团减少，分子间缔合程度降低，更多基团暴露在外。     

风化煤的微生物转化:Ⅰ菌种筛选及转化能力测定(待续)

腐植酸是风化煤的主要成分,一般水溶性和生理活性很低,直接应用效果很差,通过微生物处理有望提高其活性,开发风化煤应用新技术。本研究从土壤、根际、枯枝落叶、风化煤等多种生境中筛选到能利用风化煤或腐植酸的69个菌种,但仅有6个菌株能液化风化煤,出现小液珠或使培养基染成黄褐色至黑色。液体培养条件下,风化煤失重率达到47.69％(山西风化煤)和39.54％(内蒙古风化煤),紫外和红外光谱分析表明风化煤经微生物作用后,不仅腐植酸被溶解出来,同时被分解,分子中-OH增加、C=O基团减少,分子间缔合程度降低,更多基团暴露在外。     

风化煤腐植酸活化效果研究及其缓释肥生产工艺探讨

为提高风化煤中腐植酸的活化效率,采用氢氧化钾和熔融尿素的活化及络合工艺,对风化煤中的惰性腐植酸进行脲碱双效活化。结果显示,与未处理的样品相比,活化后的样品总腐植酸含量增加4.0%~6.4%,游离腐植酸含量增加2.6%~3.9%,水溶性腐植酸含量提高15.67~25.75倍。结合常规复合肥生产工艺,将脲碱活化后的腐脲液喷浆造粒,形成活性腐植酸缓释肥。该工艺将风化煤腐植酸双效活化与复合肥生产相结合,操作简单、成本低、生产能力大,具有极好的应用前景。     

超声波对风化煤中腐植酸活性的影响研究

采用超声波法活化风化煤中腐植酸,探讨水煤质量比、超声波功率、活化时间对风化煤中游离腐植酸产率的影响。结果表明,超声波活化风化煤腐植酸的最佳条件为水煤质量比8∶1、超声波功率500 W、活化时间40min。在此条件下风化煤中游离腐植酸质量分数为8.36%,较活化前提高了7.67倍。     

腐植酸缓控释肥的生产工艺及控释性能研究

研制并完善了腐植酸缓控释肥的生产工艺,对腐植酸缓控释肥生产过程中的温度、风化煤粒度、黏结剂与风化煤质量比(B/H)等参数进行了研究,同时对腐植酸缓控释肥的养分释放特征进行了测定。结果表明:生产时的温度显著影响其控释效果,70℃和80℃条件下制得的产品养分控释性能好;风化煤的粒度也是影响其释放率的关键因素,粒度越大,肥料养分释放越快;B/H越大,肥料养分释放速率越慢;黏结剂对腐植酸缓控释肥养分释放控制的贡献率大于风化煤。     

腐植酸复肥生产中风化煤腐植酸化学活化条件分析

分析当前腐植酸复肥生产中常用的酸催化氧解法和碱溶酸析法（酸法和碱法）的活化条件对风化煤腐植酸活化率的影响,探索了两种方法在复肥生产中最佳的腐植酸活化条件.研究表明,风化煤腐植酸最佳活化条件分别为：酸法采用硝酸、硫酸或二者混酸为活化剂,每克风化煤需纯酸量0.5 ～ 1.5 mL、反应时长15 ～ 30 min、反应温度80℃左右;碱法采用强碱或混碱、氨水为活化剂,每克风化煤需碱折纯量0.10～ 0.23 mL、反应时长30 ～ 60 min、反应温度50～90℃.     

硝酸氧化对风化煤中腐植酸含量的影响

研究了硝酸浓度、氧化时间及煤酸比对提高风化煤中腐植酸含量的影响。结果表明,当煤酸比为０．４、硝酸浓度为３３％、氧化时间３０ｍｉｎ时,风化煤的腐植酸含量可由２９．５％提高到６１．４％     

Identification of peat and leonardite using humification parameters and Isoelectric focusing (IEF): A first approach

Several samples of peat and leonardite (organic fossil material of vegetable origin) and of humic extracts from peat and leonardite were characterized using some humification parameters and isoelectric focusing (IEF). The HA/TOC and the humification rate (HR) show values lower than 60% for peat and higher than 70% for leonardite samples. These two parameters are useful to distinguish peat from leonardite, but unable to identify the organic materials in the humic extracts. Peat an leonardite samples and their humic extracts were characterized using IEF and evaluating the quantitative distribution of the bands of the profile. The group of bands in the range from pH 4.8 to 5.5 (region C) is characteristics in all samples. In particular, the relative area is less than 55% for peat and humic extracts from peat and higher than 60% for leonardite and humic extracts from leonadite.     

Laboratory and modelling study of the hygroscopic properties of two model humic acid aerosol particles

The hygroscopic properties of aerosol particles, composed of two different commercially available humic acids, have been investigated in the temperature range 293–295 K as a function of relative humidity using an electrodynamic balance. The measured mass growth factors of Sigma-Aldrich humic acid sodium salt (NaHA) and leonardite humic acid (LHA) at 90% relative humidity are 1.87±0.02 and 1.20±0.05, respectively. There is a general agreement between the results described in this study with previous TDMA results, which are undertaken with smaller particle ensembles and shorter aerosol–water equilibration times. The measured mass growth factors of Sigma-Aldrich humic acid sodium salt (NaHA) and leonardite humic acid (LHA) at 90% relative humidity are 1.87±0.05 and 1.20±0.05, respectively. The UNIFAC model was used to calculate the relationship between water activity and the concentrations of a modelled LHA molecule, and thus the hygroscopicity. The LHA molecule was modelled by both the Steelink monomer and the Northeastern–Temple–Birmingham humic acid monomer structural models.     

Structural elucidation of humic acids extracted from Pakistani lignite using spectroscopic and thermal degradative techniques

The present paper describes the characterization of Pakistan lignite coal, derived humic acids (HAL) and nitrohumic acids (NHA) along with the standard leonardite humic acids (LHA). The study utilized chromatographic and spectroscopic techniques to characterize the structure of coal and derived materials. Pyrolysis coupled to gc/ms was conducted with and without methylating agent (tetramethyl ammonium hydroxide). The pyrolysis study resulted in releasing mainly fatty acid methyl esters, different series of hydrocarbons and α, ω-dicarboxylic acid methyl esters. Triterpenoids, syringic and ρ-coumaric compounds and aromatic compounds derived from lignin moieties were also detected. Fourier transform infrared (FT-IR) and NMR data helped to evaluate the influence of coal rank on regeneration and nitration processes with respect to chemical structural composition of coal and derived materials. FT-IR spectra of four materials were similar except that NHA showed an absorption band at 1532 cm⁻¹, thus confirming the presence of -NO₂ groups. ¹³C NMR indicated higher aromaticity and less hydroxylalkyl material in HAL than NHA. The elemental composition and acid functional group content of four materials were also reported.The combination of results from different analytical techniques gives an improved understanding of the Pakistan coal nature and helpful for its future utilization.     

腐植酸物质对盐碱化中低产田土壤理化性质及玉米影响的研究

通过田间试验探讨了复合改良制剂、草炭、风化煤等腐植酸类物质施用对盐碱化中低产田土壤理化性质及生长作物的影响，结果表明：复合改良制剂、草炭、风化煤施用对土壤理化性质均有积极的影响，与对照相比达到显著水平。玉米产量的方差分析表明，复合改良制剂处理与草炭、风化煤等处理差异显著，与对照差异极显著，增产率均达到30．67％以上。     

有机氮肥对马来西亚沙捞越州酸性土壤玉米干物质产量及铵态氮和硝态氮含量的影响

腐殖质中的腐植酸和黄腐酸可以提高土壤中可交换性铵（NH4＋）的回收率。这两种酸固定和保持NH4＋的能力已经在许多研究中得到了证实,二者通过提高植株的光合作用速率、促进根系发育影响植物的生长和养分吸收。因此,本研究调查了这两种酸（液态）对玉米干物质产量、土壤铵态氮和硝态氮（NO3-）含量的影响。根据液态有机氮肥的组成,采用标准方法分离提纯腐植酸。有机氮肥在玉米种植后第10天、第28天分别施入盆栽土壤,然后在种植后第54天或孕穗期采集植株和土壤样品。土壤样品分析PH、铵态氮和硝态氮含量,植株样品测定干物质产量。结果表明,在酸性条件下,液态有机氮肥（黄腐酸、腐植酸或二者同时施用）的施用可以提高土壤中NH4＋的累积量。随土壤活性碳储量的增加,腐植酸分子上羧基官能团对土壤NH4＋的吸附能力增强。然而,酸含量较低时对干物质产量的影响明显减小。各处理间硝态氮的有效性没有达到统计上的差异显著水平。较低的PH值能抑制土壤硝化作用进程,同时降低土壤NO3-含量。这表明液态腐植酸和／或黄腐酸在提高尿素利用效率方面发挥着重要作用。然而,与腐植酸分子特性有关的作用机理还需要进一步详细研究。本研究为液态和叶面有机肥料的发展提供一定的依据。     

Volatilization of ammonia from urea-ammonium nitrate solutions as influenced by organic and inorganic additives

Fertilizers containing urea can suffer from nitrogen (N) loss through ammonia volatilization, resulting in reduced effectiveness of the fertilizers. The loss of N may be reduced by use of organic or inorganic additives.Laboratory experiments were conducted on surface soil samples (0–15 cm) from two agricultural soils (St. Bernard and Ste. Sophie) to determine the impact of ammonium thiosulfate (ATS), boric acid, and a humic substance from leonardite, on NH₃ losses from surface-applied urea-ammonium nitrate (UAN) solutions. Experiments were carried out using moist soil samples in closed containers. Evolved NH₃ was carried out of the containers and trapped in boric acid solution using an ammonia-free humidified air flow.Total NH₃ losses in these experiments ranged from 12.1 to 21.3% of the N applied. The reduction in NH₃ volatilization (expressed as % of added N) due to additives ranged from 13.6 to 38.5% and 3 to 36.3% in St. Bernard and Ste. Sophie soils, respectively. More NH₃ volatilized from the boric acid or humic treated UAN solutions than from ATS-UAN solutions.Boric acid, ATS, and the humic substance, all significantly reduced urea hydrolysis in both soils in comparison to the untreated UAN solution. Further, the humic substance and boric acid treatment induced significant reduction in NO₃-formation. The results suggest that humic substance and to a lesser extent boric acid may function as urease and/or nitrification inhibitors. ATS treatment, particularly at higher levels increased NO₃-formation in both soils. The reason for this increase in nitrate formation is not clear.     

Fermentative production of mitomycins by Streptomyces caespitosus

Production of mitomycin antibiotics by Streptomyces caespitosus was increased by the utilisation of molasses (1.0%) treated with 0.01 % potassium ferrocyanide and corn steep liquor (0.9 %). Three different fermentation media were used for the fermentation production of mitomycins. Appropriate amounts of ammonium sulphate, soluble starch, ferrous sulphate, magnesium sulphate, potassium dihydrogen phosphate, sodium chloride and calcium carbonate increased the antibiotic yield when added to the fermentation medium containing molasses and corn steep liquor. The addition of some individual amino acids, vitamins and organic acids to a base fermentation medium did not improve or increase its performance.     

以紫茎泽兰沼渣制作腐殖酸肥料的实验研究

以制作农残降解剂后紫茎泽兰的残渣残叶为原料,通过对其进行不同TS浓度的发酵实验,探究其适用于发酵的最佳浓度;并对发酵后沼渣的氮、磷、钾、腐殖酸等成分进行测定。结果表明,TS浓度为11.25%时产气较多;残渣腐殖酸含量与市场腐殖酸复合肥相近,但氮、钾元素相比含量较少。该实验可以为资源化利用紫茎泽兰、制作新型腐殖酸肥料提供参考依据。     

Application of Perfluorooctylalumina in the Ozonated Decomposition of Humic Acids

The present study deals with the application of ozone with perfluorooctylalumina in humic acids decomposition. Ozonation with perfluorooctylalumina addition destroys the complex structures in humic acids into relatively simple ones and color removal based on ADMI (American Dye Manufacture Index) measurement was greater than 95% in all tests. The rate of humic acids decomposition was described by using a first-order rate expression with respect to the decrease of A₂₅₄. A central pH level (pH 7) and perfluorooctylalumina addition is helpful in humic acids decomposition. The modified-Nernst equation could be used to predict humic acids decomposition at varying reaction conditions.     

Kinetics and Mechanism of Humic Acids Degradation by Ozone in the Presence of CeO2/AC

This work investigated the catalytic ozonation of humic acids extracted from landfill leachate in the presence of CeO₂/AC with focus on the kinetics of humic acids degradation. It was confirmed that the degradation of humic acids mainly took place in the solution bulk. The direct and indirect reaction constants of ozone against humic acids were determined. By analyzing the contributions of direct ozone oxidation and indirect ?OH radicals oxidation to humic acids removal, it was found that ?OH radicals oxidation predominated at all pH, indicating that the catalytic ozonation of humic acids with CeO₂/AC involved ?OH radicals mechanism.