中原经济区粮食生产的区域差异及其政策启示

中原经济区优越的农业生产条件和突出的粮食区位优势,决定了自身的战略定位及其在国家粮食安全体系中的重要地位。但全区范围内各粮食产区、各地市粮食生产情况差异较大,使得全区粮食工作面临较为复杂的局面。对此,应采取切实措施,一方面科学规划,加快推进以河南省为中心、辐射周边地区的粮食生产核心区建设,因地制宜地优化粮食作物结构与区域布局,提高全区粮食综合生产能力;另一方面还应适时建立全区粮食工作的沟通、协调机制,加强信息沟通和技术交流,促进粮食生产的全面协调发展。     

育种小麦籽粒力学特性的有限元分析

在建立育种小麦籽粒几何模型与有限元计算模型的基础上,运用有限元分析方法对小麦籽粒在压载作用下不同受力部位的应力分布进行了分析,获得了育种小麦籽粒在不同施力位置的压载作用下的力学性质,从而为深入研究育种小麦籽粒的损伤机制、优化脱粒装置提供理论依据。经模型仿真计算和试验结果相比较,得出育种小麦籽粒宏观破裂位置与破裂方向与有限元分析是一致的。在种子腹面施加压缩载荷时,种子的宏观破裂是沿腹沟处的应力裂纹;在种子顶面施加压缩载荷时,种子的宏观破裂是从底面两侧开始,在胚顶部与胚乳共生处相交,而后沿胚中部向下扩展的裂纹;种子的宏观破裂是由内部裂纹引起。     

纳米Al2O3粉及Al2O3基纳米晶复合陶瓷断裂韧性的研究

陶瓷材料具有高硬度，耐磨，耐腐蚀及耐高温等特点，但其脆性问题始终困绕着人们，近年来的研究发现，当陶瓷材料的晶粒变得很细小时，其强度和断裂韧性均有很大程度提高。本文研究了纳米Ａｌ２Ｏ３粉的制备及民型，烧结，研究了用纳米粉Ａｌ２Ｏ３烧制成的纳米晶Ａｌ２Ｏ３基复合陶瓷的断裂韧性与其晶粒尺寸间的关系。     

Change in the nanostructure of winter rye grain as a result of extrusion

The results are given of a comparative analysis of the nanostructure of rye grain and extrudate specimens indicating micronization of grain components during extrusion. Biochemical data are obtained which agree with the results of atomic force microscopy and confirm destructuring of rye grain biopolymers, which promotes an increase in the nutritional value of the extrudate.     

Observations of the liquid-crystal analog of the abrikosov phase

Freeze-fracture transmission electron micrographs of the smectic A(*) phase confirm the twist grain boundary model of Renn and Lubensky. The fracture surface has an undulating structure with a 0.5-micrometer helical pitch parallel to 4.1-nanometer smectic layers. The layers are disrupted by a lattice of screw dislocations oriented normal to the helical axis. Optical diffraction shows that rotation of smectic blocks occurs in discrete steps of about 17 degrees ; hence, the screw dislocations are 14 to 15 nanometers apart and the grain boundaries are 24 nanometers apart. These observations show that the SmA(*) phase is the liquid-crystal analog of the Abrikosov phase in superconductors.     

籼型杂交稻米质现状及其遗传改良

分析了福建省近几年来审定的籼型杂交水稻米质主要性状 ,认为目前杂交稻米质较差的主要原因是垩白率高、垩白度大、胶稠度低、直链淀粉含量高等 ,提出了稻米品质遗传改良的途径 .米质性状是遗传性状 ,杂交稻米质状况与亲本的米质状况密切相关 .利用米质性状的遗传规律 ,加强优质 A、R系的选育 ,才能从根本上解决杂交稻米质差的问题     

高地钩叶藤的主要物理力学性能研究

为构建健全的棕榈藤数据库、合理开发利用棕榈藤资源提供理论基础,以高地钩叶藤为研究对象,研究其主要物理力学性质及两种方式下的断裂韧性.结果 表明,高地钩叶藤的气干密度、绝干密度和基本密度分别为0.44、0.46和0.36 g·cm3.体积气千干缩率和体积全千干缩率的变化范围分别为2.91％～8.11％和7.71％～11.36％,干缩各向异性较大.高地钩叶藤的抗弯弹性模量、抗弯强度、抗压强度、抗剪切强度和冲击韧性分别为804.10 MPa、49.95 MPa、33.12 MPa、4.77 MPa和184.02 kJ·m-2.三点弯曲法测得其横纹断裂韧性为1870 kN·m-3/2,紧凑拉伸法测得其顺纹断裂韧性为77.8 kN.m3/2,说明高地钩叶藤的横纹断裂韧性比顺纹断裂韧性大得多.     

考虑损伤时材料的断裂应力

工程结构的损伤分析、寿命预测及材料细观损伤机理与材料的强韧化研究，具有十分重要的工程意义，并具有广阔的发展前景。本文研究考虑损伤时材料的断裂应力，推导出了在表面能密度有限的情况下，损伤断裂应力的计算公式。     

小麦品种间不同穗粒位籽粒蛋白质及其组分积累规律的研究

利用强、中、弱三种筋型小麦品种 ,研究了不同穗位和粒位籽粒蛋白质及其组分的积累规律。结果表明 ,各部位籽粒蛋白质及其组分遵循相同的积累规律 ,体现了籽粒充实过程中氮代谢总趋势的一致性。不同粒位籽粒蛋白质积累相对含量 ,从开花后 12天开始 ,所有处理均表现为 :强势粒 >弱势粒 ;不同穗位籽粒蛋白质积累的相对含量 ,不同品种不同施肥处理表现并非完全一致。表明籽粒着生部位和发育时间的早晚及生理机制的差异影响蛋白质的积累过程及最终合成 ,且这种差异受施肥调控 ,并具有一定的基因型差异。     

新疆粮食安全线测算与分析

国际上通用的粮食安全的新概念是"要保证任何人在任何时候都能买得起他所需要的食品".2000年以来,国际和国内粮食产量低于消费量的情况连年出现,但目前我国总体上粮食仍是供大于求,库存充裕,市场稳定.新疆粮食安全线测算结果:粮食年产量安全线750×104 t;粮食年播种面积警戒线120×104hm2;储备粮安全线100×104 t,其中:国家储备粮85×104 t,新疆自治区储备粮15×104 t.在现有粮食耕地面积、粮食单产和粮食综合生产能力的情况下,新疆粮食生产和供应处在安全的范围之内.从中长期来看,新疆粮食综合生产能力,特别是农业基础设施建设仍需要加强.新疆有全国最大的后备宜耕地资源,应该为国家的粮食安全做出贡献.     

Identification of QTLs for grain size and characterization of the beneficial alleles of grain size genes in large grain rice variety BL129

Grain size is one of the most important agronomic components of grain yield. Grain length, width and thickness are controlled by multiple quantitative trait loci(QTLs). To understand genetic basis of large grain shape and explore the beneficial alleles for grain size improvement, we perform QTL analysis using an F2 population derived from a cross between the japonica variety Beilu 129(BL129, wide and thick grain) and the elite indica variety Huazhan(HZ, narrow and long grain). A total number of eight major QTLs are detected on three different chromosomes. QTLs for grain width(q GW), grain thickness(q GT), brown grain width(q BGW), and brown grain thickness(q BGT) explained 7 7.67, 36.24, 89.63, and 39.41% of total phenotypic variation, respectively. The large grain rice variety BL129 possesses the beneficial alleles of GW2 and q SW5/GW5, which have been known to control grain width and weight, indicating that the accumulation of the beneficial alleles causes large grain shape in BL129. Further results reveal that the rare gw2 allele from BL129 increases grain width, thickness and weight of the elite indica variety Huazhan, which is used as a parental line in hybrid rice breeding. Thus, our findings will help breeders to carry out molecular design breeding on rice grain size and shape.     

基于声发射技术的木材损伤过程监测

利用声发射测试和力学实验相结合的方法,研究了东北常见的阔叶材树种山杨在动态载荷下的声发射演变过程.研究发现径向纹理不通直的试件比通直的声发射撞击数要多,而且增加的趋势较快,但是在试件断裂前,声发射撞击数相差不大;随着时间和载荷的变化,声发射撞击数增加快慢可以体现材料在受力条件下的完全弹性、弹性为主和粘性为主的粘弹性共存3种状态;声发射信号的声发射率和上升时间可以预测材料开始断裂进入危险期的和材料大量纤维断裂进入严重危险期的2个“临界点”.     

Improving the efficiency of postharvest grain processing

The existing means of mechanizing the grain drying process are analyzed and their main short-comings are revealed. The proposed new devices for drying grain make it possible to reduce expenditures of energy on the given process while providing the necessary quality of the finished product and fulfilling environmental safety of the process. The method and results of investigations of the grain drying process in the proposed devices are given and the efficiency from introducing the proposed means of mechanization into the postharvest grain process production cycle is calculated.     

Expert system techniques applied to grain marketing analysis

Grain marketing problems are often relegated to human experts because they involve the integration of objective and subjective information with experiental knowledge. An expert system was developed that incorporates this knowledge to assist grain producers in marketing their crop. The methods used to develop the rule-based system are discussed. Expert system technology was found to be useful for representing the human expertise necessary to make grain marketing decisions. The program guarantees a systematic analysis of marketing alternatives, provides consistent conclusions, and successfully incorporates the diverse information needed to make marketing recommendations. In addition, the human expert's decision-making process was improved through the formalization of his grain marketing expertise.     

对江苏粮食生产与农村经济发展关系的探讨

本文分析了江苏的粮食生产与人口、耕地、经济发展的关系。预计到2000年,江苏人口将达7032万,对粮食的需要量将达370—376亿kg。这要求粮食单产比1985年提高20％。要增加粮食产量,必须增加对农业的投入,保持适度规模的粮食种植面积。在粮食生产中,应当坚持综合生产的观点。     

湖南省粮食生产可持续发展水平测度指标体系构建研究

在明确湖南省粮食生产可持续发展的必要性的基础上，选取湖南省2004—2019年粮食生产指标数据，运用层次分析法构建包括4个一级指标和16个二级指标的湖南省粮食生产可持续发展水平测度的评级指标体系，并采用熵值法进行赋权。研究结果表明，影响湖南省粮食生产可持续发展的主要因素是资源发展和经济社会发展。因此，应在保障粮食种植资源合理使用的情况下实现农民持续增产增收，如加强农田水利设施建设，推进土地流转以促进规模经营等，以实现湖南省粮食可持续发展。     

Significant breeding properties of inbred maize lines as the basis for creating new,higher yielding hybrids

Data are given on the dynamics of water loss from grain of elite maize lines during ripening and on their photosynthetic-fluorescence properties based on the effects and nature of structural and functional changes in thylakoid membranes and chemical structures of grain tissues.     

Isotopic compositions of cometary matter returned by Stardust

Hydrogen, carbon, nitrogen, and oxygen isotopic compositions are heterogeneous among comet 81P/Wild 2 particle fragments; however, extreme isotopic anomalies are rare, indicating that the comet is not a pristine aggregate of presolar materials. Nonterrestrial nitrogen and neon isotope ratios suggest that indigenous organic matter and highly volatile materials were successfully collected. Except for a single (17)O-enriched circumstellar stardust grain, silicate and oxide minerals have oxygen isotopic compositions consistent with solar system origin. One refractory grain is (16)O-enriched, like refractory inclusions in meteorites, suggesting that Wild 2 contains material formed at high temperature in the inner solar system and transported to the Kuiper belt before comet accretion.     

谈建立国家粮食安全体系的必要性

我国的粮食安全问题是一个值得高度重视的问题。建立国家粮食安全体系是从国情出发 ,保证粮食供求基本平衡的需要 ,是国家通过国际市场调节国内粮食市场供求关系的需要。     

不同小麦品种对土壤重金属镉吸收能力初探

In order to select the low accumulation wheat varieties on the soil heavy metal contaminated plots, 14 representative wheat varieties were selected for field experiments in this study. The results showed that with the increase of cadmium concentration in the soil, the cadmium content of different varieties of wheat grains was also increasing, which had a high risk of planting wheat exceeding the standard. In this experiment, 11 varieties of wheat grain cadmium exceeded the standard, and 3 varieties met the safety standard. When the soil cadmium concentration reached 6.07mg / kg, the increasing trend of cadmium content in the stalk was obvious, indicating that the wheat reduced the transfer of cadmium to the grain, which may be related to the genetic shape of the plant. The stalk transfer coefficient of Xinwheat 26 was the largest and the grain transfer coefficient of Benong 207, indicating that high cadmium stress inhibited cadmium transfer across parts of the crop.