COMPUTER ALDED DESIGN OF FORMING CUTTER FOR REVISING INVOLUTE HELICAL

In this paper, a calculation method of forming cutter contour of involute helical with arbitrary easement is presented, the segmantal arcs of the best uniform approximation and tolerance to fit smoothly the cutter contour points are used the profile on the cross section of the helical is calculated and the design of the cutter is examined. The method can be used to design precision forming cutter of involute helical with the arbitrary easement. It is valuable in engineering application.     

Marker analysis for quantitative traits in sugar beet

Many economically important traits are inherited quantitatively and are analysed by breeders in replicated field trials. If dense maps are available, chromosomal regions containing quantitative trait loci (QTL) can be identified and this opens up the possibility of preselecting for quantitative traits in the laboratory. In this study, QTL analysis for yield and yield components in sugar beet is used in two different populations tested in several environments in both populations, QTL were detected for all traits investigated, and their predictive value in breeding schemes was analysed by correlating predicted with observed values. Tolerance to Rhizomania, caused by a gene on chromosome 3, was the main source of genotype‐environment interaction in one population, allowing selection on a QTL basis within macro‐environments with or without Rhizomania infestation, respectively. No clear results were found for the second population tested in environments with and with‐out Cercospora infestation. Consequences for breeding strategies are discussed.     

Two major genes for kernel weight in rye

Previously, kernel weight in rye was considered mostly as a quantitatively inherited trait. F₁ plants from parents showing a great difference in kernel weight were selfed and the segregating F₂ population was analysed with molecular markers. Two simple sequence repeats markers, one on chromosome 5 and the other on chromosome 7, were found which allowed the genetic analysis of two major genes acting in a complementary way. The analysis of major genes is an advantage in breeding for this important economic trait. In addition it can provide more insight into the genetic structure of this character. This is, in turn, also a prerequisite for future investigations of this trait at the molecular level.     

Quantitative chromosome map of a representative indica rice

The somatic chromosomes of standard indica diploid rice, IR 36, were squashed on glass slides and stained with Giemsa. The condensation patterns (CP) of prometaphase chromosomes were quantitatively analysed using CHIAS III software. The relative length and centromeric index (CI) were converted from CHIAS III to numerical data and calculated by EXCEL program. The ideogram based on CP of indica rice was established. There were 2 pairs of satellite chromosomes and the result was confirmed by fluorescence in situ hybridization using 45S rDNA as a probe. This revised version was published online in July 2006 with corrections to the Cover Date.     

Parameter Design for Machining Quenched Internal Helical Gears by EDM

Aiming at the problem of machining quenched internal helical gears, a method and its equipment are discussed and designed, which is used for machining quenched internal helical gears by EDM. Its characteristic and principle are proposed. The modifying design of the electrode gear and the calculating method of its modification coefficients is presented. Analyzing for the error of the machining equipment is done. The results show that this problem can be solved by EDM, the electrode gear is the modification gear of machined gear and the machining accuracy can be improved by controlling errors.     

不同水生植物－微生物系统去除水体氮磷能力研究

目前,中国湖泊水体的富营养化环境现状令人堪忧。如何有效利用更多具有经济价值的水生植物—微生物系统去除氮、磷（特别是氮）具有非常重要的意义。通过对不同总氮（总磷一定）浓度下香根草、水葫芦、水芹等水生植物—微生物系统培养水质、根际细菌总数及植物体氮、磷含量进行监测,来分析其水质动态变化规律,以及水质参数、根际细菌总数及水生植物之间的相关关系;揭示水生植物—微生物系统中水生植物的吸收作用和根际微生物系统对净化水质的作用。试验分析得出：3种水生植物去除营养盐氮、磷的能力各有不同,在所设置的3个总氮（TN）浓度下,各有一种植物能够达到最好的处理效果,且能较好地促进根际细菌的生长。比较而言,水芹系统对高浓度氮的吸收能力强,水葫芦系统对高浓度磷的吸收能力强。     

Relationship between vernalization requirement and winter hardiness in doubled haploids of barley

Summary Progeny lines of chromosome-doubled haploids from crosses between one winter and four spring barley varieties were analysed for winter hardiness and vernalization requirement in the field. About one quarter or less of the offspring lines required vernalization under field conditions showing that winter versus spring habit of growth is controlled by at least two pairs of genes. The vernalization requirement could be measured quantitatively by testing a few plants in a greenhouse after artificial cold treatment during germination. The individual winter lines tested required from two to seven weeks of vernalization in order to flower as early as possible. The cold treatment had no effect on the time of flowering in the spring lines.Winter hardiness varied from zero to 100% plant survival in the field. The majority of the lines requiring vernalization survived better than 90% and the survival of the rest was at least 60%. The winter survival of the spring lines varied from zero per cent (about one third of the lines) to 100%. Hence, it is possible to obtain lines of good winter hardiness without requirements for cold treatment. Conversely, a selection for vernalization requirement has a positive effect on winter hardiness.     

Genetic dissection of root architectural traits by QTL and genome‐wide association mapping in rapeseed (Brassica napus)

Variation in root architecture is essential for the adaptation of plants to target environments. A non‐destructive gel‐based mini‐rhizotron system was used for root architecture trait phenotyping. This system has facilitated the visualization of root architectural traits in large genotype collection of rapeseed including 94 double haploid (DH) lines from “Express617” x “V8” and 439 inbred lines (ASSYST diversity set). A high‐density Express617‐V8 linkage map was used for quantitative trait loci (QTLs) identification in DH population based on standard composite interval mapping. 6K SNPs were analysed for association mapping of root traits in ASSYST diversity set. A large variation, broad segregation and medium–low heritability of root architectural traits, primary root length and growth rate, lateral root number, lateral root length and lateral root density, were observed. In the double haploid population, 11 QTL regions, and in the diversity set, 38 significant marker–trait associations were detected. Significant marker–trait associations proved that these are quantitatively inherited traits controlled by multiple genes which revealed to proceed for genetic improvement and selection of rapeseed lines with improved root system.     

Mapping of quantitative trait loci conferring resistance to bacterial wilt in tobacco (Nicotiana tabacum L.)

Tobacco bacterial wilt (TBW) is one of the most serious tobacco diseases in the world. Studies have shown that tobacco resistance to TBW is quantitatively inherited. This study aimed to map quantitative trait loci (QTL) conferring TBW resistance. An F_2 : 3 population containing 237 lines was developed from a cross between two flue‐cured tobacco cultivars, ‘Yanyan 97’ (YY97; moderately resistant to TBW) and ‘Honghua Dajinyuan’ (HD; highly susceptible to TBW), and a linkage map consisting of 201 simple sequence repeats (SSR) markers and spanning a total length of 2326.7 cM was constructed based on the population. Field experiments were conducted 2011 and 2012, and disease symptoms were investigated three times in each year. The phenotypic data were analysed either separately or jointly for QTL mapping using the software QTLNetwork 2.1. Eight QTL with significant main effects were mapped on chromosomes 2, 6, 12, 17 and 24. A major QTL (qBWR17a) was detected on chromosome 17, which explained up to 30% of the phenotypic variation. The results can facilitate marker‐assisted selection (MAS) in TBW resistance breeding programme.     

Reference Efficiency of Planetary Gear Train

Reference efficiency of a pair of gear drive without planetary motion is the base to calculate efficiency of the whole planetary gear train. The authors find reference efficiency for speed increase is higher than that of the same drive used for speed reduction. This is different from the earlier viewpoint. New equations are derived for correctly calculating the reference efficiency of spur gear and helical gear with internal conjugate and external conjugate either in the state of speed increase or speed reduction respectively. The equations are also used to calculate efficiency of 2K-H planetary gear train.     

Analysis of diallel crosses between wheat genotypes with genetically different resistance to Pseudocercosporella herpotrichoides (Fron) Deighton

Two diallels were analysed for general combining ability (GCA) and specific combining ability (SCA) to study the resistance of crosses‐between wheat genotypes, advanced to the F₅ generation, to Pseudocer‐cosporella herpotrichoides. The parents either carried the resistance‐gene Pch‐1 or had different levels of quantitative resistance, one genotype was susceptible. At medium milk‐ripening, significant effects were‐found for GCA and SCA. GCA effects were the more important. Diallel crosses between genotypes, all carrying Pch‐1, revealed interactions‐of the gene with the genotypic background. Some combinations had a‐higher level of resistance than the best parent. In these populations'CH‐75417’ was involved as a parent. Both ‘CH‐75417’ and ‘F–210.13.4.42’ had significant GCA effects. Crosses between quantitatively resistant parents yielded populations that transgressed both parents. The increased resistance level was associated with ‘Cappelle‐Desprez’, distinguished by its high GCA. In some crosses SCA contributed significantly to an increase in resistance level. Selection for resistance within the best advanced populations is recommended since it‐takes advantage of additive gene action and the high heritability estimates based on ELISA values in plant progenies.     

Design of Cross Section Curves of Counter-intermeshing Twin-screw Kneader and Milling Cutters Blade Profiles

Basing on the theory of engagement, a design has been done for a new type of counter-intermeshing twin-screw kneader. Profile of the screw includes arcs and its envelope lines, and the profile is smooth and continuous without cuspidal points. Milling cutter blade profiles also have been calculated and corrected for manufacturing the helical parts designed and getting the clearance acquired. There may be interference between the cutter and the workpiece, so interference check must be done to insure the milling cutter and screw will not be interfered.     

基于因子分析法的聊城市农业现代化水平评价

农业现代化是农业发展的必然结果,为掌握山东省聊城市的农业现代化程度,以聊城市下辖的8个县市区为研究对象,对聊城市各县市区的农业现代化水平进行了定量分析,同时提出了加快农业现代化的建议。获取2009年聊城市统计年鉴的数据,选取10个指标,采用因子分析法对聊城市的农业现代化水平进行定量分析;通过分析发现聊城市各县市区的农业现代化水平差距较大,由高到低依次是高唐、茌平、莘县、东昌府区、阳谷、东阿、冠县和临清,同时制约各地区农业现代化水平的因素也不相同;聊城市各县市区应当因地制宜,加大农业投入,提高农业现代化水平。     

抑毒灵对烟草育苗期TMV的钝化作用

选用对烟草花叶病毒(tobacco mosaic virus,TMV)具有显著钝化作用的脱脂牛奶和磷酸三钠为研究对象,通过枯斑法测定脱脂牛奶和磷酸三钠两者复配制剂（称为抑毒灵）对烟草漂浮育苗过程中被TMV污染的基质及剪叶器的钝化作用,并利用透射电镜观察抑毒灵对病毒粒体的影响,同时采用实时qPCR对TMV含量以及寄主防御蛋白相对表达量进行定量检测。抑毒灵稀释液对TMV的钝化作用表现出时间和浓度依赖性,且不同处理间抑制率差异显著。抑毒灵与TMV接种液混合3 min后可完全抑制TMV对叶片的侵染。采用500倍抑毒灵消毒1 min以上时间抑制效果最佳。剪叶器具经稀释500倍的抑毒灵浸泡不少于5 min时对TMV的钝化效果可达100%。不同浓度的抑毒灵稀释液可显著钝化基质中的TMV,抑制TMV对烟苗的侵染和发病率,基质中TMV的含量下降74.09%~90.26%,相对防效达54.83%~85.45%。此外,所有抑毒灵处理中烟苗叶片表现正常,无药害发生。钝化病毒机制研究发现,经抑毒灵稀释液共孵育后的病毒粒体断裂成微小片段,外壳蛋白受损严重,螺旋结构和柱状基本消损完。与此同时,抑毒灵可提高防御酶PPO和PAL的酶活,还可显著诱导防御基因NPR1、PAL、PR1b和PR1a的表达。综上,抑毒灵可通过直接作用于病毒粒体和诱导寄主抗性起到抗病毒效果。     

Multi-objective dynamic optimization design of high-power wind turbine gearbox

A dynamic model of NGW helical planetary gear transmission for high-power wind turbine gearbox is established by considering these factors as errors of gears and time-varying mesh stiffness by using mass centralized method. Moreover, the random wind velocity is simulated as external seismic excitation making the results more conform to practical condition. And on this basis, this system is optimized for minimum gearbox volume and minimum component torsional acceleration with the restriction of reliability and strength restrain. The result indicates that the optimized parameters make gear transmission lightweight and the dynamic property improved so as to reduing vibration and noised.     

A major gene for flowering time in almond

Almond (Prunus amygdalus Batsch) is the earliest temperate fruit species to bloom. This restricts the economic growing of almond to frost free regions. Most almond-breeding programmes aim to develop lateflowering cultivars in order to avoid frost damage and take advantage of higher temperatures which are favourable for pollination and fertilization. Flowering time is generally considered to be inherited quantitatively but a single gene conferring very late flowering in a qualitative way has been identified in several progenies tracing back to a single mutant, ‘Tardy Nonpareil’. The effect of this allele has been studied in three progenies, showing that the effect of this major gene is modified by minor genes, quantitatively inherited, and probably influenced by inbreeding.     

Tooth contact analysis of helical beveloid gear with parallel axis

The study object of this paper is helical beveloid gears with parallel axis. Based on the gear Mshing Principles and the tooth-surface equations of pinion and gear,the mathematical model of tooth contact is developed under standard installation and installations with center distance error,axis error and multiple error respectively. The MATLAB solver is used to obtain the contact trace and the transmission error under different installing conditions and the comparative analysis is made. The results indicate that this gear drive is sensitive to axis installation errors,it forms the edge contact and cause the periodic transmission error. It can provide the foundation for designs and analysis of this gear transmission.     

红旗煤矿开采沉陷土地生态服务价值影响

为研究因煤矿地下开采造成的地面沉陷程度及其土地生态服务功能价值影响,首先利用FLAC模型对地面沉陷进行定量预测,根据地面沉陷预测结果基于GIS技术对因地面沉陷造成的土地生态服务价值进行定量分析、估算。研究结果表明：全井田最大下沉值为3 590 mm,最大倾斜值为71.8 mm,最大曲率值为2.18×10-3/m,最大水平变形值为27.3 mm/m,最大水平移动为898 mm,地表沉陷面积为8.09 km2;将导致土地生态服务价值损失537.11万元。     

基于地统计学和15N技术的湿地土壤氮素 空间运移理论探讨

地统计学是探讨自然环境要素空间异质性的有效工具，它适合于定量研究区域化变量的空间结构变异特征。湿地土壤氮素是时空连续的变异体，不论尺度大小均具有高度的空间异质性，而其变量又属于区域化变量，同时具有随机性和结构性特征。因15N示踪技术能够示踪氮素物质的踪迹，而用15N标记的示踪体在湿地土壤中运移时所产生的丰度变化又具有空间异质性，故可考虑将二者结合起来来定量探讨湿地土壤氮素的空间运移。在此，就试对这一问题进行了较为系统和完整的理论探讨。     

Energy Assessement for Procedure Rationality of Recycling Materials from Wastes

The mathematical relationship for assessing total energy consumption within a material life cycle is presented in this paper. According to the relationship,the procedure rationality of recycling waste may be assessed quantitatively.