卷烟烟气烟碱量和烟气焦油量的相关与回归分析

选择某烟草集团所有品牌(包括4个品牌)、A品牌、B品牌卷烟为研究对象,测定496个卷烟样本的烟气烟碱量与烟气焦油量,分析这2个指标在3个处理中的相关性,并建立回归方程。结果显示:用烟气烟碱作为因变量、烟气焦油量作为自变量进行回归分析,3个处理的相关系数分别为0.815、0.802、0.742,3个处理的决定系数分别为0.665、0.643、0.55,说明这2个指标在3个处理中相关性较大。所有品牌、A品牌、B品牌的回归方程分别为y赞=-0.299+0.121x、y赞=-0.327+0.121x、赞y=-1.079+0.184x,3个回归方程均达到极显著差异,说明可以将这3个回归方程作为比较理想的预测模型。

卷烟烟气焦油量的ARMA预测模型研究

[目的]为计算机辅助配方研究提供理论依据。[方法]以同一品牌不同批次卷烟的烟气焦油量为研究对象,采用时间序列分析法,建立了卷烟烟气焦油量的预测模型,并进行了模型预测验证。[结果]ARMA(22,)模型的AIC、LF和FPE值在各模型中均最小,所以选择ARMA(2,2)为卷烟烟气焦油量的预测模型,即:(1-1.622 q-1+0.844 q-2)y(t)=(1-1.836 q-1+1.02 q-2)e(t)。根据对模型残差序列进行的白噪声检验判定,建立的ARMA(2,2)模型是显著有效模型,模型预测验证表明模型预测精度达99.51%,平均相对误差为0.49%,属于一级(优等)模型。时间序列一般用于短期预测,不能用于长期预测。[结论]该研究建立的卷烟烟气焦油量的ARMA(2,2)预测模型的预测精度高、误差小,可以用于卷烟烟气焦油量的短期预测。

叶丝宽度对卷烟烟气焦油量的影响

在其它条件不变的情况下，研究了叶丝宽度对卷烟烟气焦油量的影响。结果发现，叶丝宽度对卷烟烟气焦油量的影响并非一简单的渐变曲线关系，而是一Ｖ字形曲线。即叶丝宽度为某一值时，卷烟烟气焦油量最低。对烤烟讲，该值在０．８～０．

两种不同取气位置对空压机的影响分析

文中介绍了目前车用空压机的取气方式、取气位置、主要故障模式和对应的主要影响因素;并针对不同的空压机取气位置进行了整车对比验证分析。结果表明:远离增压器取气、直接在空滤后取气的取气方式,能够有效地减少空压机进气负压,更为合理;建议整车布置时能够从空压机取气位置方面进行优化设计,从而优化提升空压机性能,减少空压机随气排油量,延长空压机的使用寿命,减少用户的抱怨。

“红百顺”牌烤烟型卷烟降低焦油量的技术措施

通过采用烟草膨胀、较高透气度卷烟纸。滤嘴截留及改进卷烟配方、制丝和卷接工艺等技术措施，有效地降低了“红百顺”牌烤烟型卷烟的烟气焦油量约每支３ｍｇ，既保证了产品的感官质量，又达到了提高吸烟安全性的目的。

烤烟（40级）各等级烟叶主要理化指标分析报告

以河南烤烟（４０级）国际仿制样品为试验材料，检测各等级烟叶主要理化指标及烟气焦油量。借助于微机，计算焦油与各主要理化指标的简相关系数并进行显著性检验。进一步采用逐步回归筛选的多变量综合分析法，得出主要理化指标支互作用影响烟气焦油量的最优方程，为进一步研究各等级烟叶的质量特点或及工业应用提供参考依据。

基于烟丝成分分析的卷烟焦油预测研究

对烟丝化学成分与烟气焦油的相关关系进行探索,寻找化学成分与卷烟焦油释放量的关系,并尝试运用现代数理统计技术,找出影响卷烟焦油释放量的关键因子,构建卷烟焦油预测模型。并应用于实际预测,结果表明,大部分数据的相对预测偏差都小于5%,准确度较高。

Identification and quality evaluation of Lepidium meyenii. (Maca) based on gas chromatographic analysis of its essential oils from roots

Lepidium meyeniiWalp. （Maca）, a perennial herbaceous plant with narrow distdbution in the Andean region, was cultivated by local residents as early as 1600 B.C. It has high nutritional values and multiple medicinal effects. In recent years the plant source of Maca has been greatly scarce since Maca products are increasingly becoming popular in the world. This makes the study urgent on the identification and quality evaluation of Maca materials. In present work, four Mace samples of different origins or handlings and three other natural plants, including radish, odental ginseng and American ginseng, were investigated. Their essential oils （steam distillates） of the hypogeal parts were weighed and analyzed by GC/MS. Through comparison of the characteristics of their chromatograms, it was found that the essential oil of Maca had unique GC/MS behaviors, and the characteristic peaks produced by the major essential oil components （Phenylacetonitrile, Benzaldehyde, 3-Methoxyphenylacetonitrile, etc） were distinct. Furthermore, the chromatograms of several Maca samples showed a similar qualitative pattern except for some differences in the quantitative composition, and the percentage of total essential oils in the samples varied from 0.88 % to 1.59 %. These behaviors and technologies can be applied to the identification of Maca materials in the markets and be a supplement to assess the quality of Maca matedals.

Correlation Analysis of Meteorological Factors with Yield and Yield Components of Rapeseed

[Objective] The aim was to research relationship of meteorological factors with rapeseed yield and yield components. [Method] A field test was carried out, with meteorological information collected from local Meteorological Administration. The data were then through statistical work and regression analysis was made on correlation of meteorological factors with yield and yield components supported by DPS. [Result] The number of pod per plant is closely related to meteorological fac- tors in seedling stage. Specifically, the number is of positive correlation with precipi- tation in seedling stage and of negative correlation with average temperature and sunshine hour. The number of grain per pod is of positive correlation with precipita- tion in seedling stage and negative correlation with temperature in seedling stage and sunshine hour in anthesis. Thousand-seed weight is of positive correlation with sunshine hour in seedling stage and negative correlation with precipitation in seedling stage. [Conclusion] Moisture of soils should be guaranteed by surface cov- erage in order to promote seedling growth, maintain ventilation in fields and reduce effects of rainfall on rapeseed flowering.

沟槽醋酸纤维滤棒的开发

为提高卷烟滤嘴的过滤性能,由醋酸纤维丝束滤芯、C型沟槽纯纤维素纸(定量80g/m2)和成形纸开发出醋酸纤维沟槽滤棒。该滤棒结构为沟槽滤棒与普通醋纤滤棒的二复合(1∶1)滤棒。试验结果表明,与普通醋纤滤嘴相比,C型沟槽滤棒的硬度可提高2～3个百分点;在卷烟感官质量基本保持不变的情况下,对卷烟烟气的过滤性能显著提高,同等条件下可再降低烟气焦油量2～3mg,降低幅度为13.66%～24.69%。

Intelligent prediction on air intake flow of spark ignition engine by a chaos radial basis function neural network

To ensure the control of the precision of air-fuel ratio(AFR)of port fuel injection(PFI)spark ignition(SI)engines,a chaos radial basis function(RBF)neural network is used to predict the air intake flow of the engine.The data of air intake flow is proved to be multidimensionally nonlinear and chaotic.The RBF neural network is used to train the reconstructed phase space of the data.The chaos algorithm is employed to optimize the weights of output layer connection and the radial basis center of Gaussian function in hidden layer.The simulation results obtained from Matlab/Simulink illustrate that the model has higher accuracy compared to the conventional RBF model.The mean absolute error and the mean relative error of the chaos RBF model can reach 0.0017 and 0.48,respectively.

Void Fraction Measurement in Oil-Gas Transportation Pipeline Using an Improved Electrical Capacitance Tomography System

To measure the void fraction online in oil-gas pipeline, an improved electrical capacitance tomography (ECT) system has been designed. The capacitance sensor with new structure has twelve internal electrodes and overcomes the influence of the pipe wall. The data collection system is improved by using high performance IC (integrated circuit). Static tests of bubble flow, stratified flow and annular flow regime are carried out. Measurements are taken on bubble flow, stratified flow and slug flow. Results show that the new ECT system performs well on void fraction measurement of bubble flow and stratified flow, but the error of measurement for slug flow is more than 10%.

Overview of Past, Present and Future Marine Power Plants

In efforts to overcome an foreseeable energy crisis predicated on limited oil and gas supplies, reserves; economic variations facing the world, and of course the environmental side effects of fossil fuels, an urgent need for energy sources that provide sustainable, safe and economic supplies for the world is imperative. The current fossil fuel energy system must be improved to ensure a better and cleaner transportation future for the world. Despite the fact that the marine transportation sector consumes only 5% of global petroleum production; it is responsible for 15% of the world NOx and SOx emissions. These figures must be the engine that powers the scientific research worldwide to develop new solutions for a very old energy problem. In this paper, the most effective types of marine power plants were discussed. The history of the development of each type was presented first and the technical aspects were discussed second. Also, the fuel ceils as a new type of power plants used in marine sector were briefed to give a complete overview of the past, present and future of the marine power plants development. Based on the increased worldwide concerns regarding harmful emissions, many researchers have introduced solutions to this problem, including the adoption of new cleaner fuels. This paper was guided using the same trend and by implementing the hydrogen as fuel for marine internal combustion engine, gas turbines, and fuel cells.

Calculation on inner wall temperature in oil-gas pipe flow

Based on the energy equation of gas-liquid flow in pipeline,the explicit temperature drop formula for gas-liquid steady state calculation was derived.This formula took into consideration the Joule-Thomson effect,impact of terrain undulation and heat transfer with the surroundings along the line.Elimination of temperature iteration loop and integration of the explicit temperature equation,instead of enthalpy energy equation,into the conjugated hydraulic and thermal computation have been found to improve the efficiency of algorithm.Then,the inner wall temperature of gas-liquid flow was calculated by using explicit temperature equation and inner wall convective heat transfer coefficient of mixed flow which can be obtained by liquid convective heat transfer coefficient and gas convective heat transfer coefficient on the basis of liquid holdup.The temperature results of gas-liquid flow and inner wall in the case example presented both agree well with those in professional multiphase computational software OLGA.

Voidage Measurement of Gas-Oil Two-phase Flow

A new method for the voidage measurement of gas-oil two-phase flow was proposed.The voidage measurement was implemented by the identification of flow pattern and a flow pattern specific voidage measure- ment model.The flow pattern identification was achieved by combining the fuzzy pattern recognition technique and the crude cross-sectional image reconstructed by the simple back projection algorithm.The genetic algorithm and the partial least square method were applied to develop the voidage measurement models.Experimental results show that the proposed method is effective.It can overcome the influence of flow pattern on the voidage measure- ment,and also has the advantages of simplicity and speediness.

DEM simulation of confining pressure effects on crack opening displacement in hydraulic fracturing

Hydraulic fracture is one of the key methods in well stimulation to increase production of oil and gas.Crack Opening Displacement(COD) is of great importance in this method since it is in direct relation with permeability and production rate.In this paper COD is measured by a distinct element model which has been validated by an exact solution.A comprehensive study has been performed on confining pressure effect on COD which is neglected in the analytical solution.Numerical results showed that confining pressure considerably affects COD.A multi-parameter regression(considering effect of confining pressure,rock mass properties and fluid pressure) was performed on numerical results which resulted in an equation.The proposed equation considers the effect of confining pressure and its results are in good agreement with numerical results.

Pore-scale simulation of gas-water flow in low permeability gas reservoirs

A novel method was developed to establish a realistic three dimensional(3D) network model representing pore space in low permeability sandstone.Digital core of rock sample was established by the combination of micro-CT scanning and image processing,then 3D pore-throat network model was extracted from the digital core through analyzing pore space topology,calculating pore-throat parameters and simplifying the shapes of pores and throats.The good agreements between predicted and measured porosity and absolute permeability verified the validity of this new network model.Gas-water flow mechanism was studied by using pore-scale simulations,and the influence of pore structure parameters,including coordination number,aspect ratio and shape factor,on gas-water flow,was investigated.The present simulation results show that with the increment of coordination number,gas flow ability in network improves and the effect of invading water on blocking gas flow weakens.The smaller the aspect ratio is,the stronger the anisotropy of the network is,resulting in the increase of seepage resistance.It is found that the shape factor mainly affects the end points in relative permeability curves,and for a highly irregular pore or throat with a small shape factor,the irreducible water saturation(Swi) and residual gas saturation(Sgr) are relatively high.

Measurement of Diffusion Coefficients of Air in Silicone Oil and in Hydraulic Oil

A piston-cylinder apparatus was established to measure the solubility and diffusivity of air in dimethyl silicone oils and in hydraulic oils based on the PVT state equation of air and the solution of unsteady one-dimensional diffusion equation.The measured diffusivity-temperature relation can be well fitted by the Arrhenius equation for engineering applications.The correlation between the solute diffusivity D and solvent viscosity μ is examined.In terms of Eyring＇s activation theory,the activation in the air-silicone-oil diffusion process is quite different from that in the momentum transport of the silicone oil：the activation entropy of the former is positive while that of latter is negative.However,the activation enthalpies of the two processes are in the same order of magnitude,which leads to the observation that Dμ/T is roughly constant.

Design Features and Performance Data of a New 400 kW Biomass Gasification Power Plant of Downdraft Type

A new biomass-gasification power plant, of medium-size downdraft type, is presented and discussed in its design features and performance characteristics. Its configuration and overall dimensions, initially conceived for 800 kW, were recently re-tuned, from a functional point of view and on the base of a parallel theoretical analysis, by decreasing to about 400 kW the former nominal power level. This provision, jointly with the basic design choice of adopting a long and amply dimensioned inlet-biomass thermal pretreatment section, turned out quite effective in achieving high gasification temperatures and a low-tar content in the produced gas at fuel-to-air ratios well below the usually imposed ones, to the advantage of the heat value of the product-gas. The paper discusses the numerical analysis results which helped to properly re-adjust the operational parameters of the gasifier and then presents the experimental performance data of the overall power plant including biomass consumption, gasification temperatures, gas production, composition and pollutants content, cold-gas conversion efficiency and global electric efficiency. Special care is devoted to investigating the issue of a significant production of carbon-containing particulate matter in the product gas, which turns out made up of char and fixed carbon much more than of tar species.