Oscillation Theorems of Systems of High Order Nonlinear Delay Partial Differential Equations

Partial functional differential equations come from many mathematical models in physics,biology,engineering and other fields,which have strongly practical background.The oscillation theory is the one of the important branches of qualitative theory of partial functional differential equations. Therefore,it is of great theoretical and practical value to research the oscillation of partial functional differential equations.The anthors study the oscillation of the systems of a class of high order nonlinear delay partial functional differential equations.By using Green's theorem and Riccati transformation,they obtain some sufficient criteria for oscillation of all solutions of the systems under two kinds of different boundary value conditions,which are illustrated by some examples.These results offer the foundation of mathematical theory for solving the practical problems of the above fields.     

Global Attractors for a Class of Pattern Formation Equations

A class of pattern formation equations is treated, the existence of its global attractor is considered and some estirnates of its dimension are given. This sort of pattern formation equations relate to turbulence phenomenon in chemistry and combustion, so it is of great physical importance. Besides, its important theoretical value lies in that the equation contains differential operator of the fourth order in space. The global attractor exists after a series sophisticated estimates by the means of interpolation inequity and embedding theorems in sobolev spaces. Furthermore, some estimates on its fractal dimension are given.     

The Multiple Solutions for a Class of Quasilinear Elliptic Equations

A three critical point theorem is proved. As its applications, Dirichlet problem for a class of quasilinear elliptic equations cf second order is considered.     

The Existence of the Nontrivial Solutions to a Class of Quasilinear Elliptic Equations Involving Supercritical Exponents

under the assumptions that (r)=O(rb)as r and*相似文献   

秸秆还田深度对小麦蔗糖转化及产量形成的影响

在大田条件下研究了小麦秸秆不同还田深度下小麦蔗糖含量及其有关酶活性,结果表明秸秆还田处理条件下,灌浆期间旗叶蔗糖含量及磷酸蔗糖还原酶（SPS）活性、籽粒蔗糖含量和酸性转化酶（AI）活性均高于普通耕作处理。在各不同深度秸秆还田处理中,15 cm深度秸秆处理在灌浆前期上述指标均有较高的表现,而花后21 天左右则低于还田25 cm处理,灌浆后期下降幅度较大;而穗下节间蔗糖含量还田25 cm 处理在花后7 天左右超过其他处理,因而蔗糖滞留量较高。在秸秆还田25 cm 处理条件下,小麦籽粒产量达到最高,其穗数也最多,而穗粒数与15 cm还田处理差异不显著,千粒质量也较低。     

高效液相色谱法测定菜用大豆鲜籽粒VC含量

为建立菜用大豆鲜籽粒VC含量的高效液相色谱测定方法，采用30 g/L偏磷酸溶液低温提取样品后，进行高效液相色谱分析，色谱柱为Agilent Eclipse XDB-C18柱（4.6 mm×250 mm×5 μm），流动相为1 g/L偏磷酸溶液∶甲醇=96∶4（V/V），流速0.8 mL/min，检测波长243 nm，柱温25 ℃，以保留时间定性，外标法定量。结果表明：VC质量浓度范围为2~40 μg/mL时，其与峰面积呈良好的线性关系（R2=1.000），平均加标回收率为108.14%，相对标准偏差为1.70%。所建立的方法操作简便，灵敏度高，分离度好，结果准确，重复性也比较好，适用于测定菜用大豆鲜籽粒VC含量，为优质菜用大豆的选育和生产提供技术支持。     

基于分数阶灰色模型的生鲜电商产品销量预测研究

新型冠状病毒的爆发,使供应链受到了不良影响,蔬菜水果等生鲜商品线下批发零售受阻,生鲜电商却迎来了新一轮的发展.从生鲜消费者角度出发,通过构建分数阶灰色预测模型对生鲜产品的需求量进行预测,并引入甘福园生鲜电商销售数据进行验证,得到柠檬、车厘子、苹果及火龙果4种水果拟合值的平均绝对百分比误差(MAPE)分别为8.61％、7.15％、7.16％、6.81％,其值均小于灰色预测模型和一次指数平滑法,且由该模型得到预测值的平均绝对百分比误差均小于10％,结果表明该模型适用于生鲜电商产品销量预测.     

褪黑素测定方法及玉米、水稻种子中褪黑素含量的分析研究

褪黑素（melatonin,缩写MT）是一种吲哚类色胺（N-乙酰-5-甲氧基色胺）,MT被证实广泛存在于生物有机体中。本试验利用玉米、水稻种子作为材料,探索种子中MT含量的测定方法、并初步了解玉米和水稻种子中MT含量情况。结果表明：(1)用高效液相色谱法（HPLC）来检测种子中MT含量是可行的, 褪黑素在0.01～1.20mg/kg浓度范围内,其标准曲线的回归方程为Y＝643436X－2446.1,R2＝0.9998,平均回收率达94.11%;（2）玉米、水稻两种粮食作物种子中含有褪黑素成份,且不同种间、品种间MT含量差异很大。玉米品种MT平均含量为96.5PPb,变幅为0～2034PPb;水稻平均为16.0PPb,变幅为0～264PPb。     

Identification of quantitative trait loci for drought tolerance at seedling stage by screening a large number of introgression lines in maize

The maize genome hosts tremendous phenotypic and molecular diversity. Introgression lines (ILs), developed by continuous backcrossing to recurrent parents, could provide a unique genetic stock for quantitative trait locus (QTL) mapping. Using maize lines from six heterotic groups of different ecological zones, we developed >500 BC₂F₂ IL sets by crossing 11 inbred lines (as recurrent parents) with >200 local maize inbred lines (as donor parents). Of them, 34 IL sets were selected as a subset for drought tolerance screening and a total of 417 ILs survived under severe water stress at seedling stage. One set of 32 surviving ILs, derived from Chang7-2/DHuang212, was used for QTL mapping with simple sequence repeat markers covering the whole genome, with seven QTL detected. Furthermore, investigating all surviving ILs, we identified two common regions in bin 3.04, corresponding to marker intervals bnlg1904–umc1772 and umc1223–bnlg1957, respectively, which shared high genetic variation in three IL sets. Our results indicated that selective genotyping can be used to identify genetic loci for complex traits. The ILs, highly selected for drought tolerance in this study, provide a unique set of materials for both genomic studies and development of enhanced germplasm resources.     

Effect of Neem Leaf (Azadirachta indica L.) on Growth and Yield of Low Land Rice

The farmers of tropical Asia are applying neem leaves to rice fields as green manure traditionally. Neem cake blending of urea is recommended for inhibition of nitrification and increasing nitrogen use efficiency. Field experiment conducted at the Tamil Nadu Agricultural University, Coimbatore, India, during kharif and rabi seasons in 1984–85 with a short duration (105 days) rice cv. IR 50 showed that application of fresh neem leaf at 5 t/ha or dry neem leaf 1.25 t/ha with urea resulted in higher N recovery per cent and N response ratio and gave increased grain yield compared to the yield obtained due to the application of urea alone. Besides increasing the grain yield, neem leaf application could save about 50 per cent N application and give greater net returns to the farmer.     

含双边界序列植物双价表达载体的构建

转基因植物的安全性是基因工程改良作物的一个重要问题.构建含双边界序列（双T-DNA区）载体,将选择标记基因和目标外源基因分开在不同的T-DNA区,通过转基因植株有性杂交及后代分离,可在转基因后代中获得无选择标记的转基因安全植株.将2个外源基因置于同一载体上,可以提高其共转化的效率.本研究构建了1个中间载体pAHC17-PTA和1个含双边界序列的植物双价表达载体pDB13PS.pAHC17-PTA含有由Ubiquitin启动子引导的具有抗虫效果的半夏凝集素基因（PTA）.pDB13PS含2个独立的T-DNA区,在其中一个T-DNA区,含两个目的基因的完整的表达盒,一个是由Ubiquitin启动子引导的半夏凝集素基因（PTA）,另一个是由水稻胚乳特异表达启动子（Glutelin-B1 promoter）驱动的马铃薯高赖氨酸蛋白基因的cDNA（SB401）.pDB13PS的成功构建,为提高PTA和SB401的共转化效率和获得无选择标记的转基因后代植株奠定了基础.     

大豆耐盐相关基因STL的克隆与分析

利用RACE技术从大豆中克隆出一条耐盐相关基因STL(GenBank登录号为DQ234265),该基因全长为1286bp,其中编码区为717bp,编码一个由238个氨基酸组成的蛋白质。STL与拟南芥的耐盐蛋白STO(salttoleranceprotein,GenBank登录号NP_849598)具有63.6%的同源性。RT-PCR分析发现,当用1mol/LNaCl处理大豆叶片不同时间时,大豆STL的表达量并未发生显著变化,与拟南芥STO的表达模式相似,推测STL在大豆中也具有类似的耐盐功能。     

普洱地区茶树种质资源茶多酚组成的聚类分析

高效液相色谱检测了普洱地区35个茶树(C.sinensis var.assamica (Masters) Kitamura)种质资源,包括20份古茶树资源,7个新选育品系、3个地方群体种、4个特异种质资源和对照品种(云抗10号),一芽二叶春梢中茶多酚各组分含量,并根据各组分相对含量对其进行了聚类分类.结果表明,所有种质...     

水稻极度分蘖突变体的分离和遗传初步研究

通过EMS诱变处理栽培稻粳灿89(Oryza sative L.indica JX89）种子，从M2代植株中筛选得到一株突变体，其植株形态表现为叶细、色淡、植株矮化和极度分蘖。在将近一年的营养生长过程中，分蘖总数达到2000多个，命名为极度分蘖突变体（Excessive tillering mutant）ext37.ext 37自交所得M3和M4代植株表现同一表型。突变体自交及其与JX89和丰矮占5号（FAZ-5）发杂交F1、F2代结果表明该突变为显性遗传方式，可能涉及两对等位基因。为了观察突变基因对下游基因表达影响的程度，取生长期44天的亲本JX89和突变体ext37的节间分生组织提纯细胞总RNA，进行基因表达谱差异显示分析。结果表明突变体与亲本的基因表达模式有明显的差异，说明可能是处在上游调控基因的突变影响了下游许多基因的表达。目前有关分子生物学的进一步研究正在进行中。     

Glucosinolates Determined by HPLC in the Seeds of Microspore-Derived Homozygous Lines of Rapeseed (Brassica napus L.)*

Microspore culture was employed to measure the relative efficiencies of anther culture and isolated microspore culture for the regeneration of embryoids and plants of Brassica napus. The yield of embryoids and plants was at least 10-fold greater from isolated microspores than from anther cultures. Approximately 1400 microspore-derived homozygous line's, the parental varieties and the corresponding F₂ plants were grown in a field trial. Important agricultural characteristics, such as morphological homogeneity, growth rate, onset of flowering and seed setting were evaluated subjectively and seed yield and glucosinolate content of individual plants were determined. The relative concentrations of up to S different glucosinolates in these seeds were measured via an automated high performance liquid chromatography (HPLC) system. The alkenyl and indole glucosinolates, the two most important categories of glucosinolates, were found in varying proportions and were independently determined in these line's. Our results do not support the previously suggested connection between low concentrations of glucosinolates and weak growth and/or poor seed yield. Additionally, no evidence was found that the lines derived from isolated microspore culture were subjected to unexpected selection pressures that might adversely affect the diversity of the lines obtained. These results demonstrate that microspore culture is a powerful tool not only for genetic analysis bur also for practical plant breeding.     

一株产胶霉菌素菌株的ARTP诱变及筛选

试验旨在选育出胶霉菌素高产菌株,以胶霉菌素产生菌TY-009为初始菌株,利用常压室温等离子体(ARTP)诱变技术对产胶霉菌素的绿色木霉菌株进行诱变处理,并设置时间梯度,检测不同处理时间样品的胶霉菌素产量。通过平板筛选以及摇瓶复筛选出8株正突变菌株,其中产率最高达到0.86 mg/m L,较初始菌株的产率提高了45.76%。ARTP诱变方法快速、高效,对绿色木霉菌株的诱变效果良好,在提高胶霉菌素产量方面有很好的应用前景。     

大穗小麦多小穗基因的染色体定位

采用中国春单体系列对大穗普通小麦品系“88F2185”的多小穗性状进行了基因定位研究。结果表明，“88F2185”决定多小穗的基因位于其1B、3D和5A染色体上，其中3D染色体的效应最强。“88F2185”1B和3D染色体上的基因表现显性，而5A染色体上的基因表现隐性。此外，“88F2185”4D染色体上还存在减少小穗数目的隐性基因。据前人研究及本试验结果分析认为，“88F2185”5”的1B及4D染色体上具控制小穗数目的新基因。