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排序方式: 共有192条查询结果,搜索用时 15 毫秒
1.
在有机化学教学中,强调以“结构——性质”模式为中心,突出有机化学在学生专业中的作用和坚持理论教学与实验教学有机结合两个基本点,可以取得良好的教学效果。 相似文献
2.
有机化学多媒体课件设计和制作 总被引:1,自引:0,他引:1
针对《有机化学》的课程特点,以Powepoint为平台,整合由Flash和Chem3D制作的高交互性的3D分子结构演示动画和反应机理模拟动画,合成课件. 相似文献
3.
针对尾矿库、垃圾填埋场底部土层受荷后的力学变形特性,以及考虑土体固结变形与重金属污染物运移转化模式、途径的不确定性与模糊性,通过分析国内外有关污染物运移模型,以及考虑土体固结变形与重金属污染物运移耦合模型的研究现状,指出现阶段研究中存在的不足,并提出考虑土体固结变形与重金属污染物运移转化相互耦合时应加强考虑传输介质间的非均相、非线性,建立综合考虑应力场、渗流场、浓度场、化学场,以及双电层引力场的重金属污染物运移转化模型,特别是在特殊土(如膨胀土、红黏土等)中建立土体固结变形与重金属污染物运移耦合模型以及计算方法,是今后研究工作的研究重点与发展方向。 相似文献
4.
乌兰察布地区胡萝卜优化施肥方案初步研究 总被引:1,自引:0,他引:1
本试验通过正交旋转回归设计在乌兰察布地区选取氮、磷、钾和有机肥为参试变量,以胡萝卜产量为目标函数,建立了胡萝卜产量与参试因子间的数学模型,得出了各变量与产量的主次关系及各因素对产量的效应。最后,通过模拟寻优获得了本试验地条件下胡萝卜产量高于6000kg/667m2的施肥方案:N(8.06-8.72kg/667m2)、P2O5(3.89-4.26kg/667m2)、K2O(19.10-20.45kg/667m2)、有机肥(6346-6907kg/667m2)。 相似文献
5.
李忠军 《广东轻工职业技术学院学报》2002,1(1):16-18
本文对有机化合物合成路线的控制过程中形成的干扰及排除干扰的方法进行归纳和探讨。希望它能对有机合成路线的设计有一定的参考价值。 相似文献
6.
《有机化学》CAI课件的设计和应用 总被引:2,自引:0,他引:2
黄秀山 《重庆职业技术学院学报》2004,13(1):91-92
进入21世纪以来,以计算机为核心的信息技术正在全面地改变着人们的生存和学习方式;Intemet网的日益普及为《有机化学》教学的改革带来了契机.把计算机辅助教学(CAI)引入《有机化学》的教学改革中,设计了《有机化学》CAI课件并将之应用到具体的教学过程中. 相似文献
7.
Carcinogenic and mutagenic polycyclic aromatic hydrocarbons (PAHs) generated in coal combustion have caused great environmental health concern. Seventeen PAHs (16 high priority PAHs recommended by USEPA plus Benzo[e]pyrene) present in five raw bituminous coals and released during bituminous coal combustion were studied. The effects of combustion temperature, gas atmosphere, and chlorine content of raw coal on PAHs formation were investigated. Two additives (copper and cupric oxide) were added when the coal was burned. The results indicated that significant quantities of PAHs were produced from incomplete combustion of coal pyrolysis products at high temperature, and that temperature is an important causative factor of PAHs formation. PAHs concentrations decrease with the increase of chlorine content in oxygen or in nitrogen atmosphere. Copper and cupric oxide additives can promote PAHs formation (especially the multi-ring PAHs) during coal combustion. 相似文献
8.
Measurement and analysis of soil nitrogen and organic matter content using near-infrared spectroscopy techniques 总被引:2,自引:0,他引:2
Near infrared reflectance (N1R) spectroscopy is as a rapid, convenient and simple nondestructive technique useful for quantifying several soil properties. This method was used to estimate nitrogen (N) and organic matter (OM) content in a soil of Zhejiang Province, Hangzhou County. A total of 125 soil samples were taken from the field. Ninety-five samples spectra were used during the calibration and cross validation stage. Thirty samples spectra were used to predict N and OM concentration. NIR spectra of these samples were correlated using partial least square regression. The regression coefficients between measured and predicted values of N and OM was 0.92 and 0.93, and SEP (standard error of prediction) were 3.28 and 0.06, respectively, which showed that NIR method had potential to accurately predict these constituents in this soil. The results showed that NIR spectroscopy could be a good tool for precision farming application. 相似文献
9.
In the present article an attempt is made to elucidate the organic colorants commonly encountered in the Russian avant-garde painting palette by a combined art historical, documentary and physicochemical investigation, and to examine the influence of environmental factors on the chromatic profile originally sought by the artist. The overall approach based on written sources is confirmed by measurements on relevant paintings. The documentary research deals with the influences of Orthodox iconography, folkloric art, and occidental modernist tendencies on the Russian avant-garde palette, and studies the effects of contradictory historical processes in the chromatic profile of individual paintings. In the experimental section a series of colorants are investigated concerning the effects of accelerated ageing on experimental painting tables, prepared as watercolor and gouache layers on paper ground. The resulting samples are subjected to colorimetric and spectroscopic measurements, and analogous analytical procedures are applied on samples taken from selected paintings. A systematic comparative study of all data permits evaluation of the materials used in terms of their stability towards extrinsic factors, and proposal of degradation routes in order to assist museum curators and conservators in every concrete case related to the broad spectrum of pigments examined. 相似文献
10.
Zoe Eirini Papliaka Konstantinos S. Andrikopoulos Evangelia A. Varella 《Journal of Cultural Heritage》2010,11(4):381-391
This study examines the materials of a contemporary pictorial artwork, belonging to the Macedonian Museum of Contemporary Art in Thessaloniki (Greece), and needing conservation. The combined use of micro-FTIR and micro-Raman spectroscopy allowed the identification of almost all painting materials. Moreover, the stability of a series of synthetic pigments towards accelerated ageing is investigated in applications using the contemporary binding medium styrene-acrylic copolymer. The pigments in question are: Hansa yellow PY3 and PY74, quinacridone PV19 and PR122, naphthol AS PR112, phthalocyanine green PG7 and blue PB15, dioxazine PV37, van Dyck brown PBk11, ivory black PBk9, and titanium dioxide PW6. The organic pigments were applied alone or mixed with titanium dioxide, in rutile form or as a mixture of rutile/anatase. The experimental swatches were subjected to ageing tests, and subsequently studied as to colour changes by means of colorimetric measurements, and as to the molecular structure differentiations by infrared spectroscopy in reflectance mode. The ageing tests included exposure to high temperature and humidity (90 °C, 60% RH) and to ultraviolet radiation (350 nm, 30 °C and 50% RH, with a substantial temperature increase at 90 °C for 3 days). The greater colour difference is caused by high temperature and humidity, whereas paint layers containing TiO2, and especially the mixture of the forms rutile/anatase, prove very susceptible to ultraviolet radiation, demonstrating a significant colour difference and extended molecular changes. 相似文献