关于《焙烤工艺学》课程教学改革与思考

在教学实习、实践的基础上,系统分析了《焙烤工艺学》传统教学方式存在的弊端,提出《焙烤工艺学》在教学理念、教学内容、教学方式和方法、教学环境等方面进行创新,从而很好的激发学生的学习兴趣,培养学生的实践创新能力,提高教学质量。     

不同施氮方式对玉米农艺性状及产量的影响

科学施肥是实现玉米高产高效的重要保障.本研究通过田间试验,比较了5种施氮方式对玉米农艺性状及产量的影响.这5种施肥方式分别是无肥对照、高氮一炮轰（农民习惯）、一次性施用缓控释肥、底肥＋1次追肥（拔节期）、和底肥＋2次追肥（拔节期和抽雄期）.结果表明,两次追肥的增产效果好于一次追肥及施用缓控释肥,各处理均好于一炮轰施肥.与无肥对照相比,两次追肥、一次追肥、缓控施肥、高氮一炮轰的增产效果分别是64.4％、60.1％和58.7％、55.0％.建议提倡在玉米生育中、后期,采用两次追肥的方式,从而提高玉米产量.在没有条件追肥的地区,也可以考虑一次性施入缓控释肥.     

家域研究进展

家域是动物行为学和保护生物学的重要概念之一,它在动物对资源环境的适应与选择,种群密度及社会关系等生态学过程研究中有着重要的作用。对家域的内涵、特征、估算方法(包括取样方法,样本含量,位点数据自相关,模型评价等)等方面进行阐述,总结了家域估算模型的发展过程及发展方向,评述了3种主要家域估算模型的优势与不足,并结合最新的理论和应用,对未来的研究方向提出建议。     

莲藕的活性成分研究进展

综述了莲藕的活性成分种类、莲藕活性成分的药用和食用开发利用价值及莲藕活性成分的提取方法3个方面的研究进展,并对其今后的研究进行了展望。     

橄榄的采收、贮藏及增值加工研究进展

橄榄富含多种生物活性物质,果实及其提取物具有清热解毒、清咽利喉、降血糖、抑菌抗炎和抗氧化等药理活性,有着较高的食用和药用价值.近年来,橄榄产业得到了全面发展,橄榄产品逐渐丰富.本文从橄榄的适期采收、贮藏保鲜技术和精深加工等方面进行综述,以期为橄榄产业的持续发展提供新思路.     

Shortcut Approach Alternative to the Step‐by‐Step Conventional Soil Phosphorus Fractionation Method

Abstract

In an attempt to characterize the phosphorus (P)–supplying capacity of a soil and to understand the dynamics of soil P, a procedure was followed whereby consecutive extraction procedures were carried out on a soil sample, first by dialysis membrane tubes filled with hydrous ferric oxide (DMT‐HFO), followed by subsequent P fractionation procedure. However, this combined method is lengthy and time‐consuming, and an approach to shorten these P desorption studies in soils was important. The major objective of this article, therefore, was to present a shortcut method as an alternative approach to the combined fractionation method. Comparison of the sum of DMT‐HFO‐P_i, sodium bicarbonate (NaHCO₃)‐P_i, sodium hydroxide (NaOH)‐P_i, D/hydrochloric acid (HCl)‐P_i, and C/HCl‐P_i extracted by a conventional step‐by‐step method with the sum of DMT‐HFO‐P_i and a single D/HCl‐P_i extraction as a shortcut approach for all extraction periods resulted in a very strong and significant correlations. Both these methods were correlated with maize grain yield, and it was found to be highly significant. This study revealed that this shortcut approach could be a simplified and economically viable option to study the P dynamics of soils especially for soils where the P pool acting as a source in replenishing the labile portion of P is already identified.     

New,Comprehensive Soil Chemical Methods Book for Australasia

The 1992 Australian Laboratory Handbook of Soil and Water Chemical Methods (the handbook) of Rayment and Higginson defines much of the contemporary soil chemical methodology used in Australia for soil fertility and land-resource survey assessments. In addition, codes from the handbook identify methodological details in Australian soil databases, while the codes summarize most tests used for certification purposes by the Australasian Soil and Plant Analysis Council (ASPAC) in its interlaboratory soil proficiency testing programs. A worthy, comprehensive replacement was required as the handbook is out of date in places and out of print. This article provides information on the handbook's replacement with a new book by Rayment and Lyons, titled Soil Chemical Methods-Australasia. Method codes and other strengths of the handbook have been retained and many new tests have been added. There are new chapters on acid sulfate soils, total miscellaneous elements, and miscellaneous extractable elements, plus inclusions and improvements throughout. Modern analytical techniques, such as flow-injection analysis, inductively coupled plasma–mass spectroscopy (ICP-MS), and potential alternatives to chemical testing offered by near-range and midrange infrared diffuse reflectance spectroscopy, are included. Examples of new additions include the Mehlich 3 “universal” soil test (and derived environmental P tests) and methods for potentially mineralizable nitrogen, labile carbon, particulate organic carbon, and charcoal. Around 200 methods are fully described, while information of measurement performance at different concentrations is provided where credible data were available from multiple, interlaboratory proficiency programs of ASPAC. Procedures for the chemical testing of water are no longer included, except where relevant to saturation extracts of soils. While there are informative and much expanded method preambles and reference lists, the new 2011 book has its focus on methodology. A scheme to agree on recommended methods for different soils and regional locations is outlined.     

Comparison of Copper,Manganese, and Zinc Extraction with Mehlich 1, Mehlich 3, and DTPA Solutions for Soils of the Brazilian Coastal Tablelands

Deficiency of micronutrients is increasing in crop plants in recent years in Oxisols and Ultisols in the tropics. The predominant soils in the coastal tablelands of Brazil are Ultisols and Oxisols, with low cation exchange capacity and kaolinitic clay mineralogy. Soil copper (Cu), manganese (Mn), and zinc (Zn) extracted by the Mehlich 1 solution, currently used in the regional soil-testing laboratories, were compared with those extracted by the Mehlich 3 and diethylenetriaminepentaacetic acid (DTPA) solutions in a greenhouse experiment with 10 soil samples (0–20 cm deep) collected from representative Ultisols and Oxisols from various locations in the region. Corn was grown as a test crop, and its dry matter and micronutrient uptake was measured at 30 days of growth. Soil Cu, Mn, and Zn extracted with the three solutions were significantly correlated (0.65–0.95 range for r values), with the Mehlich 3 solution extracting greater quantities than the Mehlich 1 and DTPA solutions. Zinc and Cu taken up by corn plants were significantly related to their soil-extractable levels measured at harvest with all three of the solutions, except for Zn DTPA. However, similar relations between plant uptake and soil extractable Mn were poor, except for DTPA extracting solution.     

Nitrogen-Use Efficiency in Lowland Rice Genotypes under Field Conditions

Rice is staple food for more than 50% of the world's population. Nitrogen (N) is one of the most yield-limiting nutrients for lowland rice production around the world. Two field experiments were conducted at two locations for two consecutive years to evaluate N-use efficiency of 12 lowland rice genotypes. Growth, grain yield, and yield components were significantly influenced by N as well as genotype treatments. Location?×?year?×?genotype and location?×?year?×?N interactions were significant for most of the growth, yield, and yield components, indicating influence of these factors on yield and yield components. Overall, the most N-efficient genotypes measured in terms of grain yield were BRA 031032, BRA 031044, and BRA 02654 and the most inefficient genotypes were BRS Jaçana, BRS Fronteira, and BRA 02674. Genotypes had linear and quadratic responses to added N in the range of 0 to 200 kg ha^?1. Nitrogen significantly influenced plant height, shoot dry weight, panicle number, and 1000-grain weights. Nitrogen-use efficiency (kg grain per kg N applied) varied from 33 to 49 kg grain per kg N applied, with an average value of 40 kg grain per kg N applied. The genotype BRA 031044 produced the greatest N-use efficiency, and the lowest N-use efficient genotype was BRS Fronteira. There was a significant linear association between N-use efficiency and grain yield.     

Application of the Multicomponent Spectral Fitting Algorithm in the Estimation of the Correct Value of Phosphorus determined by ICP OES in Soil Samples

ABSTRACT

Phosphorus (P) determination by Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES) in soil extracts is affected by copper (Cu) content and may lead to misinterpretation of the results. In this study, Multicomponent Spectral Fitting (MSF) method for the quantitative determination of P in the presence of Cu was tested. Phosphorus determination by UV/Vis molecular absorption spectrometry (COL) was free from copper interference. Phosphorus determination by ICP OES at wavelengths of 213.618 and 214.914 nm without use of MSF were subject to interference when Cu concentration was greater than 1.5 and mg L^?1 and 3.5 mg L^?1, respectively. When the P: Cu ratio in solution was 1:1 and 2:1, on average, there was no significant difference between the P determined by COL and by ICP-OES using MSF. In matrices containing Cu, it is indicated to use the P spectral line at 214.914 nm because it was less sensitive to Cu concentration than spectral line at 213.618 nm.