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131.
In order to improve university laboratory teaching and practical education under the background of information technology, as well as overcome the difficulty for practical training, develop a virtual simulation experiment platform for rapid pyrolysis of natal materials and high-performance liquid chromatographic (HPLC) detection of its components. The experiment integrates the actual operation process of the plant to produce cleaved products by rapid pyrolysis of biomass with HPLC detection. The virtual experiment is divided into biomass sample pretreatment, rapid biomass pyrolysis, bio-oil extraction, and HPLC determination of complex components, making the biomass cleavage workshop "real" through simulation. This virtual simulation experiment fully integrates the utilization of biomass resources and basic chemistry courses (such as organic chemistry, instrumental analysis, chemical engineering principles, etc.), which are widely involved in agricultural and forestry majors with advantageous characteristics value.  相似文献   
132.
离子交换树脂纯化酪蛋白磷酸肽研究   总被引:3,自引:0,他引:3  
通过单因素实验和正交试验确定了使用D-201型大孔强碱性阴离子交换树脂纯化酪蛋白磷酸肽(CPPs)的操作条件为:洗脱温度40℃、洗脱酸(HCI)浓度0.2mol/L、洗脱速度2.3ml/min、进样浓度2%(w/v),进一步应用HPSEC技术分析考察了离子交换树脂纯化后含磷洗脱峰分子量分布情况,并计算了产品氮磷比与纯化收率.  相似文献   
133.
玻璃化转变是高分子专业教学中的重要内容,转变过程中自由体积的变化和分子链段的运动是理解玻璃化转变的难点。在计算机上使用分子模拟的方法得到三维的可视化图形,可以更直观地观察到自由体积和分子链的变化。提炼近年分子模拟技术在玻璃化转变研究中的最新科研成果,得到既有理论基础又适合本科教学的课程素材。分子模拟可以实现了仪器测试无法达到的超快速升降温,并与仪器测试得到的实验结果相对照,验证了普通实验很难验证的理论观点,从而拓展了本科实验的范围,达到了很好的教学效果。  相似文献   
134.
 It is argued that results of uncertainty calculations in chemical analysis should be taken into consideration with some caution owing to their limited generality. The issue of the uncertainty in uncertainty estimation is discussed in two aspects. The first is due to the differences between procedure-oriented and result-oriented uncertainty assessments, and the second is due to the differences between the theoretical calculation of uncertainty and its quantication using the validation (experimental) data. It is shown that the uncertainty calculation for instrumental analytical methods using a regression calibration curve is result-oriented and meaningful only until the next calibration. A scheme for evaluation of the uncertainty in uncertainty calculation by statistical analysis of experimental data is given and illustrated with examples from the author's practice. Some recommendations for the design of corresponding experiments are formulated.  相似文献   
135.
136.
Scientific research training is an essential part of undergraduate learning, which plays an important role in improving students' knowledge utilization and scientific literacy. Taking the participation process of "Energy conservation and emission reduction competition" as an example, this paper briefly introduces the undergraduate scientific research training of students majoring in polymer materials and engineering from their own perspective, and the way to combine the discipline and school characteristics to reflect the thinking of engineering students in scientific research and practical application.  相似文献   
137.
PVC disulfide (2SPVC) was synthesized by solution crosslink and its molecular structure was confirmed by infrared spectrum. 2SPVC's specific area is 36.1 m2·g-1 tested by stand BET method, and granularity experiment gives out the particle size of d0.5= 11.3μm. With SEM (Scanning Electron Microscope) experiment the surface morphology and particle shape of 2SPVC were observed. Cyclic voltammetry (scan rate: 0.5 mV·s-1) shows that 2SPVC experience an obvious S-S redox reaction in charge-discharge process. When 2SPVC was used as cathode material for secondary lithium battery in a 1 mol·L-1 solution of lithium bis(trifluoromethylsulfonyl) imide (Li(CF3SO2)2N) in a 5:45:50 volume ratio mixture of o-xylene (oxy), diglyme (DG) and dimethoxymethane (DME) at 30℃, the first discharge capacity of 2SPVC is about 400.3 mAh·g-1 which is very close to its theoretical value (410.5 mAh·g-1) at a constant discharge current of 15 mA·g-1. It can retain at about 346.1 mAh·g-1 of discharge capacity after 30 charge-discharge cycles. So 2SPVC is a very promising cathode candidate for rechargeable lithium batteries.  相似文献   
138.
As a necessary basic theory course for undergraduates majoring in chemistry, materials, pharmacy, chemical engineering, and biology, physical chemistry plays an important role in cultivating talents to meet the needs of social and economic development. Over the years, the teaching team of physical chemistry of East China University of Science and Technology has carried out the curriculum reform and innovation persistently based on "Team building as the foundation, resource building as the root, mode innovation as the soul, ability training as the origin". This paper will summarize our thinking and experience in striving for the first-class course from the aspects of first-class team construction, first-class resource construction, teaching connotation innovation, teaching mode exploration, and extract the experience that can be used as reference by teaching peers.  相似文献   
139.
热敏电阻温度计的设计与制作   总被引:1,自引:0,他引:1  
本文介绍了设计性实验“热敏电阻的设计与制作”的实施情况。说明了只要选题合适、要求恰当,设计性实验不仅可行,而且对物理实验训练的总结提高十分有效。  相似文献   
140.
热致液晶乙基纤维素与尼龙-1010共混物的研究   总被引:2,自引:0,他引:2  
在自制单螺杆小型挤出机上通过熔融共混的办法,制备了不同配比(5/95—25/75)的EC/Nylon—1010共混物.用WAXD、DSC、毛细管流变仪、力学性能测试等方法对共混物进行了研究.发现共混后尼龙-1010的形态结构有明显改变,其强度、模量都有提高,在高剪切速率下,共混物粘度大大降低.配比为1585时,这些性能的改进尤为明显.  相似文献   
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