物理化学实验课教学模式的改革与实践

分析了目前物理化学实验课的教学现状和教学中存在的主要问题,并对物理化学实验教学进行了改革和探索。改变了传统的实验教学模式,搭建了物理化学实验教学网络平台,增强了学生学习的主动性,提高了学生的实验效率和实验质量,培养了学生的创新意识和创新能力,收到了良好的教学效果。     

中学有机化学实验环己烯制备的改进

指出了中学有机化学实验环己烯的制备实验方法中存在的系列问题,并给出了相应的改进措施,改进后实验条件得到了优化,提高了产品的产率和纯度。同时实验改进后一方面减少了环境污染,实现了实验的绿色化,提高了广大师生的环保意识;另一方面减少了实验消耗和试剂用量,提高了人才的培养质量和效益。     

MTBE装置催化精馏塔捆包催化剂的应用

催化蒸馏塔内的催化剂进行了更换,弃用了原有的散装催化剂,采用了捆包催化剂,抑制了催化剂的副反应,减少了催化剂对催化精馏塔的腐蚀,有效延长了催化精馏塔的使用周期,也进一步满足了扩能改造的要求。     

患者住院费用明细在临床中的应用

住院费用明细的实施,让患者真正明白了医疗费用的每一笔开支,增加了医院的透明度,密切了医患关系,维护了医患双方的利益,赢得了患者及家属的信任,减少了医疗纠纷,树立了医院良好的社会形象。     

1万t/a异戊烯装置的设计与运行优化

对1万t/a异戊烯装置设计的优化项目进行了考察,验证了设计的有效性;分析了装置运行情况,提出了不同负荷下醚化操作的优化条件;优化了醚解催化剂的投用条件,减少了二甲醚的生成,降低了装置的甲醇单耗;控制异构化反应器的温度和叔戊醇含量,保证了2-甲基-1-丁烯的转化率,提高了产品中的2-甲基-2-丁烯的含量;异戊烯侧线出料口下方增加了1米填料后改善了产品的品质,降低了产品中其他组分的含量;装置的标定表明:装置能稳定运行,数据可靠,达到了设计指标。     

碱洗塔洗塔系统的优化

介绍了氯乙烯合成工段碱洗塔洗塔工艺流程,并针对存在的问题对其进行了优化升级,使碱洗塔自控洗塔、配碱,提高了系统的自动化控制水平,节约了水资源,也降低了废水处理系统的负荷,最大限度地提高了碱液的利用率,提高了工作效率,增加了经济效益,     

《天然药物化学》实验教学改革与实践

通过引入先进的提取技术、色谱分离技术以及结构鉴定的光谱技术,节省了时间与化学试剂,提高了实验效率。鼓励学生参加创新性实验增加了学生的学习兴趣,拓宽了学生的专业视野,增强了学生的动手操作能力,培养了学生的创新能力,提升了学生的综合实力,取得了较好的教学效果。     

国外某1000t/d项目风扫生料磨调试

本文介绍了风扫生料磨的调试经验,通过改造出磨风管,降低了磨机通风阻力,增加了磨内通风量,提高了磨机的烘干能力;通过改造中心圆尺寸,增加了填充率,提高了磨机的出力,从而提高了磨机的产量,顺利实现了达产目标。     

带式过滤机在多品种氢氧化铝生产中的应用

介绍了带式真空过滤机的工作原理及其在多品种氢氧化铝生产方面的应用情况,并对带式真空过滤机使用过程中存在的问题进行了改造。改造之后,提高了洗涤过滤效率,降低了滤饼水分,降低了能耗,提高了产量,确保了产品质量,取得了较好的经济效益。     

医学专业物理化学教学改革的探索

结合多年的教学实践,分析了医学专业物理化学教学的现状和存在的主要问题,并对物理化学教学进行了改革和探索。改变了传统的教学模式,搭建了一个新的教学平台,增强了学生学习的主观能动性,提高了学生的学习效率和质量,培养了学生的创新意识和创新能力,取得了较好的教学效果。     

The Peeling Behavior of Pressure Sensitive Adhesives from Uncoated Papers

When a tape based on pressure sensitive adhesive (PSA) is peeled from paper, either the tape comes off leaving a clean paper surface or the paper undergoes catastrophic cohesive failure which is the delamination of fiber layers in the paper sheet. The objectives of this work were to determine the links between paper properties and peel characteristics. Peel tests and microscopic analysis of a variety of handmade and commercial papers yielded the following conclusions. The tendency for paper failure is not very sensitive to surface energy. Paper roughness and density seems to be the dominant factors. A relatively smooth but weak paper will give a clean peel whereas a strong but rough handsheet or filter paper will always give paper failure. Lamination pressure is also important. Peel force increases with lamination pressure up to a limit where paper failure begins and the peel force plummets. The peel response of common paper types is mapped onto a 2-D surface whose axis reflects paper surface chemical and structural properties. It is proposed that the initiation of paper failure in peel occurs at fiber ends.     

The Peeling Behavior of Pressure Sensitive Adhesives from Uncoated Papers

When a tape based on pressure sensitive adhesive (PSA) is peeled from paper, either the tape comes off leaving a clean paper surface or the paper undergoes catastrophic cohesive failure which is the delamination of fiber layers in the paper sheet. The objectives of this work were to determine the links between paper properties and peel characteristics. Peel tests and microscopic analysis of a variety of handmade and commercial papers yielded the following conclusions. The tendency for paper failure is not very sensitive to surface energy. Paper roughness and density seems to be the dominant factors. A relatively smooth but weak paper will give a clean peel whereas a strong but rough handsheet or filter paper will always give paper failure. Lamination pressure is also important. Peel force increases with lamination pressure up to a limit where paper failure begins and the peel force plummets. The peel response of common paper types is mapped onto a 2-D surface whose axis reflects paper surface chemical and structural properties. It is proposed that the initiation of paper failure in peel occurs at fiber ends.     

Mechanical properties of polymer–paper laminates

Tensile mechanical properties of synthetic polymer–paper laminates were measured. The laminates were constructed by hot pressing a sandwich made of a sheet of paper between polymer films. There is complete penetration of the polymer inside the paper; no voids are left. Two different polymer matrices were used: poly(methyl methacrylate) and polyethylene. Several paper samples were utilized: an unoriented holocellulose paper (a strong paper), a highly oriented holocellulose paper, and an unoriented Whatman filter paper (a weak paper). The laminates contain from 0% to 50% of paper. Young's moduli and breaking strengths of the unoriented holocellulose paper laminates can be theoretically predicted from the properties of their constituents using laws of mixtures. The mechanical properties of the Whatman paper laminates are significantly higher than those predicted from the laws of mixtures. This indicates that the polymer increases the strength of the fiber-to-fiber bonds of the weaker sheets, although it does not change the bond strength of a stronger paper such as the holocellulose paper. For the oriented paper laminates, changes in Young's modulus with angle of measurement are explained by the composite materials theories if the angular variations in shear modulus are taken in to account. Changes in breaking strength with angle for the oriented laminates can be analyzed by Tsai and Azzi's theory for composite materials.     

A Study into the Influence of Paper Coatings on Paper Properties and Print Quality of Dye Sublimation Thermal Prints

The need for good quality paper for dye sublimation transfer printing has been reported previously as a principal requirement for the process. Pigmented coated papers have gained acceptance in the traditional paper printing industry, but, despite their importance, have inspired very few reports in literature about their application in heat transfer printing.

In the current work, we studied the influence of both clay and ground calcium carbonate (GCC) pigments and the incorporation of plastic pigment on the surface structure and mechanical properties of the coated paper used for transfer printing. The results showed that paper coating significantly reduced the surface roughness of the paper. The mechanical properties of the prepared coated paper, including tensile strength, stretch, tensile energy absorption (TEA), and burst index, were improved when coated compared to those of uncoated paper. The addition of plastic pigment to the coating mixture helped improve the paper's properties.

The optical density of the transfer-printed polyester fabric using the prepared coated paper was also compared with that of uncoated paper. It was shown that a slight increase in optical density was evident in the coated paper.

The possibility of producing a second polyester print from the exhaust paper was also investigated. Coated paper incorporating plastic pigment, in particular, showed higher optical density than did uncoated paper.

We found that coated paper based on clay, GCC, clay/plastic pigment, or GCC/plastic pigment consumed less dye paste than uncoated paper though producing printed fabric with higher optical density—especially in the second print.     

芳纶浆粕和芳纶纸的发展概况

介绍芳纶浆粕和芳纶纸的发展概况、应用领域及市场前景情况,对国产芳纶纸、NOMEX纸和对位芳纶纸进行简单比较,认为芳纶纸的关键技术是纤维原材料、分散流送技术、斜网成型技术和热轧技术,并对国内芳纶纸的发展提出一些看法。     

Development of a novel PPTA/cellulose composite insulation paper with low dielectric constant and improved mechanical properties by BTCA crosslinking

This study investigates the effect of 1,2,3,4-butane tetracarboxylic acid (BTCA) crosslinking treatment on the electrical properties of poly-p-phenylene terephthalate (PPTA)/cellulose insulation paper to prepare a novel composite insulation paper with low dielectric constant and good electrical performance. Three-layer PPTA/cellulose composite paper crosslinked by BTCA under various conditions, composite paper without crosslinking, directly mixed composite paper, and conventional Kraft paper are prepared. The morphology and surface chemical composition of the paper samples are characterized. Dielectric, mechanical, and thermal properties are investigated. Results show that the BTCA concentration of 0.2 mol L⁻¹ with a 180°C curing temperature is the relatively superior crosslinking condition to prepare a novel composite with low dielectric constant and good comprehensive performance. The dielectric constant and loss of the novel composite paper decrease to 3.21 and 0.392 at 50 Hz. The tensile strength of the BTCA crosslinked three-layer PPTA/cellulose composite paper (thickness: 130 μm) has reached 10.01 kN m⁻¹, increased by 41.6% than the directly mixed composite paper. The novel BTCA crosslinked composite paper also shows improved thermal stability. The BTCA crosslinking proves to be a promising method to improve the dielectric properties and electrical performance of the PPTA/cellulose composite paper.     

造纸湿强剂的合成及应用研究进展

作为重要造纸助剂之一的纸张湿强剂,可使纸张完全被水浸湿或被水饱和时仍能保持其部份强度,被广泛应用于造纸工业。文章通过对目前常用湿强剂和新型湿强剂的种类、结构、合成及应用现状的综述,结合造纸工业的发展需求,提出了造纸湿强剂向"绿色化"发展是当前研究的方向,对造纸湿强剂的合成趋势和方法进行了展望。     

纸厂浆纸动态优化产耗存数学模型研究及系统设计

针对纸厂的浆纸生产过程,通过建立浆纸动态优化产耗存数学模型,开发浆纸动态优化系统,用于计算系统的浆纸平衡情况,合理安排生产计划,预测设备维修时各工段的停车时间,并提供浆纸平衡的监控手段,避免生产过程的不正常波动.     

缩合磷酸胍阻燃浸渍绝缘纸的应用研究

纸及纸制品的阻燃是阻燃研究的重要领域之一，本文利用自己研制的缩合磷酸胍为阻燃剂研究了对浸渍绝缘纸的阻燃性能以及对其它性能的影响。通过与国家标准进行比较结果表明，该阻燃剂对浸渍绝缘纸进行阻燃处理后，不仅能获得良好的阻燃性能，而且对浸渍绝缘纸的其它性能影响小，并符合国家标准。     

废胶粉和锯末对废纸浆性能的影响

试验研究废胶粉和锯末对废纸浆性能的影响.结果表明:废胶粉/废纸浆、锯末/废纸浆和废胶粉/锯末/废纸浆复合材料的物理性能提高,且废胶粉/废纸浆复合材料的物理性能优于废胶粉/锯末/废纸浆复合材料,因此以废胶粉改性废纸浆效果较好.废胶粉/废纸浆复合材料的最佳配方为:废纸浆100(干基计),废胶粉8,防老剂D 0.2,硫黄0.2,促进剂M 0.2;最佳固化条件为150℃/10 MPa×30 min.此时材料表面比较光滑,结构紧密,排列比较均匀,废胶粉与废纸浆的相容性较好.