Set-membership estimation from poor quality data sets: Modelling ammonia volatilisation in flooded rice systems

A set-membership (bounded-error) estimation approach can handle small and poor quality data sets as it does not require testing of statistical assumptions which is possible only with large informative data sets. Thus, set-membership estimation can be a good tool in the modelling of agri-environmental systems, which typically suffers from limited and poor quality observational data sets. The objectives of the paper are (i) to demonstrate how six parameters in an agri-environmental model, developed to estimate NH₃ volatilisation in flooded rice systems, were estimated based on two data sets using a set-membership approach, and (ii) to compare the set-membership approach with conventional non-linear least-squares methods. Results showed that the set-membership approach is efficient in retrieving feasible parameter-vectors compared with non-linear least-squares methods. The set of feasible parameter-vectors allows the formation of a dispersion matrix of which the eigenvalue decomposition reflects the parameter sensitivity in a region.     

水稻叶片气孔分布与气孔密度的研究

用改良刮制法研究了水稻叶片的气孔分布与气孔密度。结果表明稻叶下表面气孔的分布不是随机的,表现出一定的规 律性。气孔在脉间区纵向排列成行;叶缘和主脉附近气孔分布较均匀;其他脉间区气孔行可分为两组,组内气孔行数因品种、 叶位和叶片上的具体部位而有差异。同一叶片气孔行数的顺序是基部>中部>尖部。稻叶气孔密度是籼稻普遍大于粳稻,且 籼稻、偏籼稻、粳稻和偏粳稻4种类型气孔密度的大小顺序为籼稻>偏籼稻>偏粳稻>粳稻,表现出明显的类型间差异。     

不同氮素水平对直立穗型水稻品种群体光合特性的影响

在田间条件下测定了两种氮素水平下直、弯穗型水稻品种的群体光合特性。结果表明：参试的两个水稻品种群体光合速率（CAP）的生育期变化为单峰曲线,在籽粒灌浆期,直立穗型品种CAP下降幅度慢于弯曲穗型品种;增施氮肥可提高CAP,并延长其高值持续期;直立穗型品种不同叶位单叶净光合速度（PN）最大值差异不明显,增施氮肥可延缓PN高值持续期,但对提高PN影响不大,于水稻开花期及乳熟期田间高氮区群体饲喂^14CO2,测定结果表明：直立穗型品种冠层中项部三片叶的光合速率最高,其光合量占单株总光合量的87.4%;弯曲穗品种测定结果与直立穗型品种相似。直立穗型品种抽穗后剑叶叶绿素含量、光合速率、比叶重、单株根伤流量和冠层生态条件大都优于弯曲穗型品种,这可能是直立患得患失同穗后CAP下降较缓慢的主要原因。     

水稻不同育苗移栽方式的比较研究

试验结果表明,摆秧的产量高于插秧,二的产量均显地高于抛秧,品种间及品种与栽培方式互作间的差异均不显。摆秧的增产机理是秧苗素质好,移栽植伤很轻,分蘖早生快发,最高茎蘖数和成穗率均较高;叶面积指数高,且变化加速度小;在抽穗前比叶重增加快,此后增加慢;在生育后期,叶层面积大且占据层次多,群体基部绿叶面积大,穗层面积大且分布集中,位置偏中上,SOD含量高,丙二醛含量低。     

Packaging‐related properties of protein‐ and chitosan‐coated paper

The mechanical and gas‐barrier properties of paper and paperboard coated with chitosan–acetic acid salt (chitosan), whey protein isolate, whey protein concentrate and wheat gluten protein were studied. Paper sheets were solution‐coated using a hand applicator. In addition, bi‐layer composites of wheat gluten and paper or paperboard were produced by compression moulding, and the chitosan solution was also applied on paperboard using curtain coating. Young's modulus, fracture stress, fracture strain, tearing strength, air permeance and oxygen permeability were assessed. The mechanical and air permeance measurements of solution‐coated paper showed that chitosan was the most effective coating on a coat weight basis. This was due to its high viscosity, which limited the degree of penetration into the paper. The proteins, however, also enhanced the strength and toughness of the paper. Compression‐moulded wheat gluten/paper or paperboard, as well as curtain‐coated chitosan paperboard laminates, showed oxygen barrier properties comparable to those of paper and paperboard coated with commercial barrier materials. None of the composites could be delaminated without fibre rupture, indicating good adhesion between the coatings and the substrates. Copyright © 2005 John Wiley & Sons, Ltd.     

营养型发酵软饮料的研究

研究利用稻加工大米的副产品碎米为主要原料 ,加入麦芽、加酶 ,进行液化、糖化、发酵等工艺 ,研制出一种发酵营养型软饮料。本产品与啤酒相比 ,可减少原料总用量的 17% ,减少麦芽用量的 2 8.6%。     

饲粮铜水平对生长猪部分生化指标的影响

“三个代表”重要思想是对马克思列宁主义、毛泽东思想和邓小平理论的继承 ,是中国共产党历史经验的科学总结 ,同时 ,也是对马克思列宁主义、毛泽东思想和邓小平理论的发展和创新。继承与创新相统一 ,坚持与发展相统一 ,是正确对待马克思列宁主义的科学态度 ,也是“三个代表”重要思想的本质特点     

不同插秧量对东北杂交稻与常规稻产量结构的影响

对东北杂交稻与常规稻的产量形成过程和产量结构进行了分析。结果表明：杂交稻比常规稻增产的主要原因在于杂交稻的经济系数显高于常规稻，这主要得益于杂交稻后期光合产物向籽粒的转移率较高。在产量结构上，杂交稻的穗粒数多、千粒重大，但穗粒数的优势主要来源于二次枝梗，这也造成了杂交稻的结实率偏低，成为限制杂交稻产量潜力发挥的瓶颈。进一步发挥杂交稻的杂种优势，需要从提高后期光合能力和提高结实率两方面人手。杂交稻与常规稻有各自适宜的栽培方式，插单苗有利于提高杂交稻的平均穗重、千粒重、结实率，并最终使产量提高；而插3苗更适于常规稻生产力的发挥。     

大穗型超级杂交粳稻辽优3072产量结构及灌浆特性研究

对北方大穗型超级杂交粳稻辽优3072进行了产量结构和灌浆特性的研究。结果表明：辽优3072在产量结构上表现出了较强的杂交优势，比对照辽粳294增产明显。辽优3072在灌浆上的特点为穗上、中、下各部间干物质充实及灌浆速率差异较小：穗下部灌浆启动早，后期灌浆速率大；整穗表现出较强的持续灌浆能力。辽优3072良好的籽粒灌浆特性是其在产量上表现出超高产的生理基础之一。同时探讨了利用水稻杂交优势选育具有特异灌浆特性的杂交组合的育种思路以及在北方冷凉稻区推广大穗型超级杂交粳稻品种的可能性。     

水稻气力抛秧原理与方案研究

在对国内外水稻钵苗移植机械综合分析的基础上提出了气力抛秧的原理，并进行了方案设计和研究。结果表明，气力抛秧原理是可行的，能有效地解决目前机械抛秧存在的问题。