不同小麦品种叶面积、叶绿素相对质量分数、根系性状及产量的研究

旨在阐明高海拔生态条件下小麦品种顶二叶光合特性与产量的关系,为高产栽培和高产育种提供理论依据.试验于2013-2014年在云南丽江以云南省主栽的5个小麦品种为供试材料,研究了不同品种顶二叶叶面积、叶绿素SPAD值、根系性状差异及与籽粒产量的关系.结果表明,不同小麦品种在开花期顶二叶叶面积、开花期和成熟期顶二叶叶绿素SPAD值、根系性状(次生根根数、根长和根干质量)上差异有统计学意义.倒二叶和顶二叶叶面积与籽粒产量呈极显著正相关,但旗叶叶面积与籽粒产量相关性无统计学意义.成熟期旗叶、倒二叶和顶二叶叶绿素SPAD值与籽粒产量分别呈显著或极显著正相关,开花期、成熟期旗叶和倒二叶叶绿素SPAD值与叶面积的乘积和籽粒产量分别呈显著或极显著正相关.高海拔生态区次生根根系发达、生育后期顶二叶维持相对较大叶面积和较高叶绿素SPAD值的协调型小麦品种(如云麦53)具有较大增产潜力.

标准Z分数与相对A分数的比较分析

本文运用比较研究的方法,深入探讨了标准Z分数,相对A分数的起源、定义、计算公式、分数的性质,两种分数在考试中的作用,在选优评价中的作用,并得出一些结论.

不同含氧官能团对煤润湿性影响的分子动力学模拟研究

为了探究不同含氧官能团对煤润湿性的影响规律,基于分子动力学(molecular dynamics,MD)理论,构建4个不同含氧官能团模拟系统(—COOH、—OH、—CO及—OCH 3),通过模拟接触角、分子相对体积分数、径向分布函数及相互作用能结果,详细分析含氧官能团对煤润湿性的影响规律。研究结果表明:模拟平衡后,在—COOH体系中水团簇的接触角为18.65°,相互作用能为-1049.19 kcal/mol,并形成371.64个氢键。在—OH体系中水团簇的接触角为25.37°,相互作用能为-563.83 kcal/mol,并形成178.03个氢键。在—CO体系中水团簇的接触角为30.10°,相互作用能为-444.25 kcal/mol,并形成58.34个氢键。在—OCH 3体系中水团簇的接触角为59.96°,相互作用能为-149.00 kcal/mol,并形成13.25个氢键。水团簇与不同含氧官能团体系的接触角越小,形成的氢键越多,相互作用能绝对值越大,对煤亲水性增强作用越好,这与分子相对体积分数和径向分布函数分析结果一致;不同含氧官能团对煤亲水性增强作用排序为—COOH>—OH>—CO>—OCH 3。研究结果可为研究煤表面润湿性及其应用提供相关参考。

论标准化考试的分数转换和解释标准化

论标准化考试的分数转换和解释标准化哈尔滨市招考办于金龙分数转换和解释标准化是标准化考试的最终环节．也是一个非常重要的环节．也许有人会问，标准化考试已在命题、实施、阅卷评分等方面实现了标准化，对误差作了严格的控制，使考试达到公平台理，考试分数已能准确地...

生物多糖溶液喷射减阻实验研究

为获得生物多糖溶液的水下减阻性能,在重力式循环水槽实验系统中,测试了瓜尔胶、黄原胶、黄蓍胶及刺槐豆胶等4种生物多糖溶液的喷射减阻特性,给出了喷射溶液速率、主流雷诺数及喷射溶液质量分数对多糖溶液减阻的影响规律。研究结果表明:4种生物多糖溶液均具有显著的喷射减阻效果,其中刺槐豆胶溶液减阻率最高(14.3%);同一主流雷诺数下,随着喷射溶液速率的提高,各多糖溶液的减阻率显著提高,减阻率达到峰值后则呈现出不同的变化趋势;多糖溶液在主流雷诺数较小(<2.0×10^(4))时减阻效果更优,提高主流雷诺数后,多糖溶液表现出差异化的减阻规律;喷射溶液质量分数过高会降低多糖溶液减阻效果,提高主流雷诺数会使多糖溶液减阻效果随质量分数的提高出现“峰值后移”现象。通过引入“喷射溶液相对质量分数”将喷射溶液速率、主流雷诺数及喷射溶液质量分数对减阻效果的影响相互耦合,随着相对质量分数的增大,4种多糖溶液的减阻率均表现出先升后降的变化规律。最后,基于相对质量分数初步阐明了多糖溶液的减阻规律。

切口试样破坏过程试验与细观数值分析

对切口圆棒试样与切口板试样进行单向拉伸试验和有限元数值分析 ,以试样最小横截面上各点变化的应力应变场为体胞演化的载荷控制条件 ,采用三维含球形微孔洞体胞模型分别对各点微孔洞长大规律进行数值模拟。结果表明 ,在试样得到的断口韧性区域内 ,微孔洞的生长速度较快 ;试样失稳前微孔洞相对体积百分数最大的区域与试验时试样的起裂位置一致 ,因而证实微孔洞的演化是导致试样材料在拉伸条件下破坏的主要原因 。

关于学生评教数据的巧妙处理

教学评价工作已在各级院校中广泛展开,许多学校将学生评教的数据作为衡量教师业务素质的重要标准,并将其与教师的聘用、职称评审、岗位津贴等教师切身利益挂钩。这就使得对学生评教数据的处理工作显得尤为重要。通过对比几种常见数据处理方法的优缺点,并结合所在学校的实际情况,对评教数据进行巧妙处理,可以大大提高数据的可信度。

基于词条向量和情感分析的新闻广告匹配模型

在新闻网页上配置广告的算法通常以信息关联度为基础,没有考虑新闻和广告之间的情感差异,容易导致错误匹配.针对目前广告匹配算法的缺陷,在关键词生成、情感分析技术的基础上,引入情感差异分析,建立了一种新的支持在线新闻与广告内容、情感相匹配的模型.该模型对在线新闻网站和广告投放商实际应用具有重要的意义.

略论大学生综合素质测评

略论大学生综合素质测评潘晓阳大学生综合素质测评是指学校根据党的教育方针中的总体教育目标，对大学生在德、智、体诸方面事先制定出具体目标、要求及规范，并依此逐项进行真实的系统的科学的检测、考核和评定，以定量的或定性与定量相结合的方式描述大学生的综合素质情...

央行独立性的测算模型研究

央行独立性的研究一直是金融领域一个重要的议题。关于央行独立性的测定和计量也自然成为独立性研究的一大主攻方向。研究中会遇到两大难题:一是可能出现两家央行的独立性分数相同,从而难以进行比较;二是只采用一种模型的思路难以覆盖各大模型的参考指标,无法得出一个相对平均和稳定的分数值。对此,提出两种测算央行独立性的模型——相对分数模型和综合分数模型,并分别进行理论分析和实证检验。

对会考试卷编制的几点思考和建议

对会考试卷编制的几点思考和建议●湖北保康县第二中学周永康要使会考更具科学性、权威性，那么，对会考全程中的两个重要环节——试卷编制，学生考试过程进行深入研究是必要的，也是迫切的。对这两个环节的研究至少要达到两个目的：试卷编制更加科学；学生考试过程更加严...

基于漫反射可见光谱无损检测生鲜牛肉和猪肉肌红蛋白

基于表面漫反射可见光谱,提出一种用于定量检测生鲜牛肉和猪肉中脱氧肌红蛋白、氧合肌红蛋白和高铁肌红蛋白的无损检测方法。将光谱检测系统采集的光谱信号转化成反射吸光度,结合多元线性回归预测生鲜牛肉和猪肉中肌红蛋白相对质量分数,同时应用经典可见分光光度法测定肌红蛋白相对质量分数以验证预测结果有效性。结果表明:表面漫反射可见光谱法可定量检测肌红蛋白,理论预测结果与实验结果之间存在显著线性关系,相关系数R2≥0.9536。基于漫反射可见光谱的无损检测方法可量化生鲜牛肉、猪肉中肌红蛋白质量分数,旨在为生鲜肉制品的品质监控提供技术支持。

高职院校招生竞争力测量探析

高职院校招生竞争力受多种因素的影响,可以从量和质两个维度,采取计划完成比和相对录取分数线比两个指标,对高职院校招生竞争力进行测量。根据2018年河南省的相关招生数据,测算出了首批国家示范性高等职业院校2018年在河南省文史类、理工类的相对招生竞争力指数,结果发现:招生竞争力受学校投放的招生计划大小、学校所处地理区域、招生专业的社会认可度等因素影响。为提升招生竞争力,高职院校应客观分析院校生源地情况,合理制定招生计划;开拓招生宣传途径,加大招生宣传力度;优化专业布局,突出专业特色。

3-D fracture network dynamic simulation based on error analysis in rock mass of dam foundation

Accurate 3-D fracture network model for rock mass in dam foundation is of vital importance for stability,grouting and seepage analysis of dam foundation.With the aim of reducing deviation between fracture network model and measured data,a 3-D fracture network dynamic modeling method based on error analysis was proposed.Firstly,errors of four fracture volume density estimation methods(proposed by ODA,KULATILAKE,MAULDON,and SONG)and that of four fracture size estimation methods(proposed by EINSTEIN,SONG and TONON)were respectively compared,and the optimal methods were determined.Additionally,error index representing the deviation between fracture network model and measured data was established with integrated use of fractal dimension and relative absolute error(RAE).On this basis,the downhill simplex method was used to build the dynamic modeling method,which takes the minimum of error index as objective function and dynamically adjusts the fracture density and size parameters to correct the error index.Finally,the 3-D fracture network model could be obtained which meets the requirements.The proposed method was applied for 3-D fractures simulation in Miao Wei hydropower project in China for feasibility verification and the error index reduced from 2.618 to 0.337.

Experimental Study on the Initial Position Distribution of Taylor Bubbles in Cryogenic Upward Inclined Tubes

An experimental study was carried out to understand the phenomena of the boiling flow of liquid nitrogen in inclined tubes with closed bottom by using the high speed digital camera.The tubes in the experiment are 0.018 m and 0.014 m in inner diameter and 1.0 m in length.The range of the inclination angles is 0-45° from the vertical.The statistical method is employed to analyze the experimental data.The experiment was focused on the effect of the inclination angle on the initial position distribution of Taylor bubbles.The formation criterion of Taylor bubbles was confirmed by analyzing the images of Taylor bubbles.The experimental results show that the initial position of Taylor bubble increased first,and then decreased with the increasing inclination angle,with the maximum at 30°.The standard deviation of the initial position of Taylor bubble in tubes was different with different inner diameters.The lognormal shape was fitted to the measured the initial position distributions of Taylor bubbles in the cryogenic tubes.

Comprehensive modeling approach of axial ultrasonic vibration grinding force

The theoretical model of axial ultrasonic vibration grinding force is built on the basis of a mathematical model of cutting deforming force deduced from the assumptions of thickness of the undeformed debris under Rayleigh distribution and a mathematical model of friction based on the theoretical analysis of relative sliding velocity of abrasive and workpiece. Then, the coefficients of the ultrasonic vibration grinding force model are calculated through analysis of nonlinear regression of the theoretical model by using MATLAB, and the law of influence of grinding depth, workpiece speed, frequency and amplitude of the mill on the grinding force is summarized after applying the model to analyze the ultrasonic grinding force. The result of the above-mentioned law shows that the grinding force decreases as frequency and amplitude increase, while increases as grinding depth and workpiece speed increase; the maximum relative error of prediction and experimental values of the normal grinding force is 11.47% and its average relative error is 5.41%; the maximum relative error of the tangential grinding force is 10.14% and its average relative error is 4.29%. The result of employing regression equation to predict ultrasonic grinding force approximates to the experimental data, therefore the accuracy and reliability of the model is verified.

Frontier Analysis of Nepalese Commercial Banks： DEA Approach

The efficiency of any organizations at manufacturing sector or service sector, profit making or non-profit making, is most important factor for survival and growth of the organization. The Data Envelopment Analysis （DEA） technique is one of the most popular and effective tool to measure relative efficiency hence is appropriate to make comparison among similar organizations with multiple output and input. This study performs frontier analysis and measures the relative efficiency of Nepalese commercial banks using DEA approach with two output and two input variables.

Analyzing the influences of two types of El Nino on Tropical Cyclone Genesis with a modified genesis potential index

To understand the impacts of large-scale circulation during the evolution of E1 Nifio cycle on tropical cyclones （TC） is important and useful for TC forecast. Based on best-track data from the Joint Typhoon Warning Center and reanalysis data from National Centers for Environmental Prediction for the period 1975- 2014, we investigated the influences of two types of E1 Nifio, the eastern Pacific E1 Nifio （EP-E1 Nifio） and central Pacific E1 Nifio （CP-E1 Nifio）, on global TC genesis. We also examined how various environmental factors contribute to these influences using a modified genesis potential index （MGPI）. The composites reproduced for two types of E1 Nifio, from their developing to decaying phases, were able to qualitatively replicate observed cyclogenesis in several basins except for the Arabian Sea. Certain factors of MGPI with more influence than others in various regions are identified. Over the western North Pacific, five variables were all important in the two E1Nifio types during developing summer （July-August-September） and fall （October- November-December）, and decaying spring （April-May-June） and summer. In the eastern Pacific, vertical shear and relative vorticity are the crucial factors for the two types of El Nifio during developing and decaying summers. In the Atlantic, vertical shear, potential intensity and relative humidity are important for the opposite variation of EP- and CP-EI Nifios during decaying summers. In the Southern Hemisphere, the five variables have varying contributions to TC genesis variation during peak season （January-February-March） for the two types of E1 Nifio. In the Bay of Bengal, relative vorticity, humidity and omega may be responsible for clearly reduced TC genesis during developing fall for the two types and slightly suppressed TC cyclogenesis during EP-E1 Nifio decaying spring. In the Arabian Sea, the EP-E1 Nifio generates a slightly positive anomaly of TC genesis during developing falls and decaying springs, but the MGPI failed to capture this variation.

HPLC Analysis of Egg Yolk Phosphatidylcholine by Evaporative Light Scattering Detector

Egg yolk phosphatidylcholine(EYPC) is being widely used in food and pharmaceutical industries nowadays owing to its surface activity,pharmaceutical usefulness,and so on.Common determination methods of phospholipids were based on the American Oil Chemists' Society(AOCS) Official Method Ja7b-91,in which n-hexane/2-propanol/acetate buffer was used as the mobile phase.In order to achieve desired results,gradient elu-tion or buffer solution was used,which made the detection process more complicated.Moreover,water or buffer solution could affect the silica gel column both on its lifespan and the separation efficiency significantly.In this study,different mobile phase and detector were used to simplify EYPC analyzing process instead of using water within the mobile phase.The optimized HPLC operating conditions are as follows:pure methanol as a mobile phase,flow rate of 1.0 ml·min-1,silica gel column(250 mm×4.6 mm,5 μm,Inertsil GLTM),column temperature 30 ℃ and low temperature evaporative light scattering detector(40 ℃,0.35 MPa) as used.Under this optimal condition,the linear relative coefficient of the standard curve is 0.998 and the recovery was in the range of 96.83%-101.58% with a relative standard deviation of 1.79%(n=6).

Variable sets method for urban flood vulnerability assessment

On the basis of dialectics basic laws and mathematical theorems of variable sets,this paper proposes a variable sets method for urban flood vulnerability assessment.In this method,the comprehensive relative membership degree of multi-indices is represented by an index relative difference degree,which follows the characteristics of dialectical philosophy and mathematics.According to the quality-quantity exchange theorem,the relative difference degree of two adjacent levels(h and h+1),whose index standard interval values cross the boundaries,equals 0 in the urban flood vulnerability assessment.On the basis of the opposite unity theorem,the sum of relative membership degrees should be equal to 1 when indices lie in the adjacent degrees h and h+1.The variable sets method is proved to be theoretically rigorous and computationally simple.This paper takes 29 cities of Hunan province as an example to assess the urban flood vulnerability,and then compares the results from this newly developed method with the assessment results obtained from the fuzzy comprehensive evaluation and fuzzy set pair analysis methods.