查询词典 variation coefficient

Chromic trioxide and chromium hemitrioxide are determined with iodometry, the coefficient of variation of chromic trioxide is 0.056%, and the recovery of marked compound is 99.82-99.83%; the coefficient of variation of chromium hemitrioxide is 1.45%,and the recovery of marked compound is 98.55-99.26%; iron is determined by complexometric titration, the coefficient of variation of iron is 1.73%, and the recovery of marked compound is 99.12-99.23%;sulfate is determined by complexometric titration, the coefficient of variation of sulphate is 0.16%, and the recovery of marked compound is

Analysis Of The Chromium Electroplating Wastewater By Oxidation-reduction And Complexometric Titration-化学工程与工艺-本文采用氧化还原滴定法与络合滴定法对镀六价铬的废水中铬酸酐，三氧化二铬，铁和硫酸根的含量进行了测定：铬酸酐和三氧化二铬用碘量法测定，铬酸酐的变异系数为0.056%，加标回收率为99.82-99.83%，三氧化二铬的变异系数为1.45%，加标回收率为98.55-99.26%；铁用络合滴定法测定，其变异系数为1.73%，加标回收率为99.12-99.23%；硫酸根用络合返滴定法测定，其变异系数为0.16%，加标回收率为

Through designing of composition and structure of the bioactive graded coating,innerstress and its distribution in the coating were analyzed and calculated, the resultsshowed that when composition distribution coefficient n was 1.5, a reasonable stressdistribution could be got, that was at the beginning of deposition the suspension containingrichly BG granules was used so that a rich BG granules layer, a good transitional layerbetween BG layer at the bottom and the coating could be obtained at the titanium alloy side,the bottom of the coating; the stress value near the interface and surface and its character,pressure stress or tensile stress, were decided by the character of its composition itself.Changing composition distribution coefficient n could only change the variation tendency ofstress in the coating, but did not change the stress distribution rule in the coating. Thethinner the coating is, the sharper stress variation in the coating is, which does not mean thatthicker coating is better because the thicker the coating is, the little the permitteddeformation of coating is, so the coating thickness should be thinner, for example, about50μm for bending applications, but for applications only bearing pure shear stress, such asroot of tooth implant, the coating can be thicker little, for instance, about 80～100μm. The study on electrification characteristic and electrophoresis deposition of HAand BG granules in aqueous and non-aqueous solution system found that EPD almost didn'toccur in aqueous solution system. However, because HA granules take position charges inabsolute alcohol, a homogeneous EPD be carried out on the cathode titanium alloy slice, but taking negative charge in absolute alcohol the BG granules not be deposited on the cathode. A guided HA crystallizing, 100～300nm, on surface of the BG granules be realized by metathetical reaction, which cover BG granules with HA microcrystals and make the covered BG granules taking position charges in absolute alcohol, sequentially realize the EPCD of the BG and HA granules on the cathode, so it is feasible to make a titanium alloy/BG/HA bioactive graded coating by making use of EPCD technology. The corrosion experiment of rich boron bioglass coating and plasma spray coating showed that split phase, rich boron and rich silicon phase, occurred during its preparation. In basic medium the corrosion behavior of 〓 BG coating showed uniformity corrosion, the corrosion mostly occurred at rich boron phase area, therefore batch formula design of BGshould avoid the occurring of split phase. The corrosion appearance of plasma spray coatingappeared a non-uniform corrosion, mostly occurred at the edge of the laminated HA moltendrops, and emerged an accelerated corrosion tendency, which will easyly lead to corrosioncrackles extending to the interface and the happening of osmotic interfacial corrosion, thatmay be one of the major reasons leading to the coating cracking-off in the later period. Thetesting results of thermal expansion coefficient of 〓 and 〓BG showed the thermalexpansion coefficient of 〓 BG matched with that of titanium alloy better, and 〓 BG couldsinter with titanium alloy into densification enamel layer at low temperature (720℃).

将Ti6Al4V合金在1000℃下进行真空热处理会降低其力学性能，且合金内的V元素会向表面富集，因此，钛合金真空热处理和表面涂层的烧结温度不能过高，即应低于其相转变点；通过对生物活性梯度涂层的组成和结构的设计，分析和计算了梯度涂层内的应力大小和分布，结果表明：对于本研究，当成分分布系数n=1.5时，可以获得较合理的涂层力学性能，即在沉积开始时，采用富含BG颗粒的悬浮液，以便在钛合金侧获得同底层BG有良好过渡的富BG涂层；梯度涂层界面和表面的应力大小、性质由材料组成本身的性质决定，改变成分分布系数，只能改变涂层内应力变化的趋势；涂层的厚薄不影响涂层内的应力分布规律，但涂层越薄，涂层内的应力变化越快，但这并不意味着涂层越厚越好，因为涂层越厚，涂层允许的变形越小，对于应用于弯曲受力部位的涂层而言，涂层应薄一点为好(50μm)；而对于仅纯受剪切应力的部位，如牙根种植体，涂层可适当加厚(80～100μm)；通过对HA和BG颗粒在水溶液体系和非水溶液体系中的带电特性和电泳沉积的研究发现，它们在水溶液体系中很难发生电沉积；在无水乙醇溶液中，HA颗粒带正电，可在阴极钛合金片上发生均匀的电泳沉积，而BG颗粒则带负电荷；利用复分解反应法，可以制得100～300nm的HA，通过诱导HA在BG颗粒表面结晶，可对BG颗粒进行表面包覆，获得了被HA包覆的BG颗粒，改变了BG颗粒表面的带电特性，使BG和HA颗粒在无水乙醇中均带上正电荷，从而实现了HA和BG颗粒在阴极上的共沉积。

Results: good standard linear curve, r = 0.9998; minimum checking limited to: 0.28μg formaldehyde, or 1.4μg sodium formaldehyde sulfoxylate; Variation coefficient 2.0%.

结果：标准曲线线性良好，r = 0.9998；最低检出限为：0.28μg甲醛，或1.4μg吊白块；变异系数为2.0 %。

With the increasing of directional backcrossing generationstransferred, variation coefficient and uniformity degree of different hybrid groupsdecreasing.

结果表明，随着定向回交世代的增多，杂交种群体内的变异幅度减小，群体整齐性逐渐提高。

On the basis of analyzing the traditional real estate investment benefit appraisement method, this paper introduces the risk variation coefficient and systematic risk degree in investment, and revises the calculation formulae of base earnings ratio and net present value, then, brings forward real estate inves.

本文在对传统的房地产投资效益评价方法分析的基础上，引入了风险变异系数和投资的系统风险度，修正了基准收益率及净现值的计算公式，提出了考虑风险因素的房地产投资效益评价方法。

Reliability ; sensitivity analysis ; correlative variable ; Markov chain ; line sampling ; variation coefficient

可靠性；灵敏度分析；相关变量；马尔可夫链；线抽样；变异系数

The content of different nutrient was variated in:change of soil organic matter in the rate of 6.32～35.83 g/kg,the coefficient variation was 29.72%,change of the soil available nutrient content was not the same,to the most obvious avail-P,the rate of change for the 4.00 to 91.60 mg/kg,the coefficient variation 68.81%,avail-N smaller the range, changes in the rate of 40～182 mg/kg,the coefficient of variation was 26.66%.The average of all soil nutrients are in the middle level of the plentiful-lack Index of available nutrient.

涿州市不同元素养分含量变异情况各不相同：土壤有机质变幅不大，变化幅度为6.32～35.83g/kg，变异系数为29.72%；土壤速效养分含量变幅不相同，以速效磷最为明显，变化幅度为4.00～91.60mg/kg，变异系数达68.81%；碱解氮的变幅较小，变化幅度为40～182mg/kg，变异系数达26.66%，各速效养分的平均值均在丰缺指标所划定的中等养分含量水平。

The standards of the different concentration had good repeatability, and their variation coefficient was in the range of

各稀释度标准品的批内重复性好，其变异系数范围为

Soil organic matter was high in Baoshan tobacco-growing areas and ranged from 1.50 g/kg to 148.10 g/kg with a mean of (32.43±12.38) g/kg and variation coefficient of 33.34%.

保山烟区土壤有机质含量较丰富，平均为(32.43±12.38)g/kg，变幅为1.50~148.10 g/kg，存在广泛的变异，其变异系数达33.34%。

The method can determine Aldrin, Dieldin and Endrin at the same time, with characters of simple approaches and strong operability Their determination results showed higher accuracy and variation coefficient.

该方法可同时测定艾氏剂、狄氏剂和异狄氏剂，并具有步骤简单，操作性强的特点，其测定结果具有较高的准确度和变异系数。

On the other hand, the more important thing is because the urban housing is a kind of heterogeneity products.

另一方面，更重要的是由于城市住房是一种异质性产品。

Climate histogram is the fall that collects place measure calm value, cent serves as cross axle for a few equal interval, the area that the frequency that the value appears according to place is accumulated and becomes will be determined inside each interval, discharge the graph that rise with post, also be called histogram.

气候直方图是将所收集的降水量测定值，分为几个相等的区间作为横轴，并将各区间内所测定值依所出现的次数累积而成的面积，用柱子排起来的图形，也叫做柱状图。