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1.
目的 探究纸张荧光增白剂含量(OBA)对色彩复制的影响,有利于准确测量颜色并实现色彩在不同设备间正确转换,准确复制颜色。方法 选择含较多荧光增白剂、含少量荧光增白剂、不含荧光增白剂3种类型的纸张,分别基于M1/M2的观察条件,测量纸白、CMYK线性色表以及IT8.7/4色表,分析M1/M2观察条件下Δb*、ΔE*值以及ICC曲线变化趋势。结果 在M1和M2观察条件下测量纸张基色b*值的差值绝对值可以确定基材中的OBA的含量,且OBA含量对颜色测量数据的影响与阶调值相关,基本呈负线性关系;在M1观察条件下测量数据生成ICC色彩特性文件,整体线性偏移蓝色,即b*值往负值线性偏移。结论 基于M1观察条件的色彩管理流程,需进一步研究荧光增白剂含量对b*值进行线性补偿校正的影响,从而减少纸张荧光增白剂对色彩管理的影响,使纸张上的颜色复制达到理想状态。 相似文献
2.
《International Journal of Hydrogen Energy》2022,47(83):35423-35436
The gas diffusion substrate (GDS) is essential in the proton exchange membrane fuel cells. Its fabrication techniques affect the performance significantly and are worthy of investigation. In this study, a manufacturing process of the GDS is proposed to understand the formation process of GDS and promote its structure and performance more pertinently. Different states during the preparation process, raw carbon paper, pre-curing, curing, carbonation, and graphitization, are characterized and measured. Experimental and numerical methods are employed to determine the relationships between microstructure, transport, and mechanical performance variation with the fabricating processes. The results show that its porosity, average pore size, and effective diffusivity decrease first and increase after curing. These parameters after graphitization are lower than that of the carbon paper (CP). The electrical resistivity increases dramatically while pre-curing and decreases gradually after curing, carbonation, and graphitization, and it is much reduced after graphitization. Moreover, mechanical measurement results show that both the picks of tensile strength and flexural modulus occur after curing. Its tensile strength shows little change after graphitization compared to the initial paper's. In contrast, the flexural modulus is improved significantly. 相似文献
3.
《International Journal of Hydrogen Energy》2022,47(61):25769-25779
Gas diffusion layer (GDL) is one of the most important components of fuel cells. In order to improve the fuel cell performance, GDL has developed from single layer to dual layers, and then to multiple layers. However, dual or multi layers in GDL are usually prepared by layer-by-layer methods, which cost too much time, energy, and resources. In this work, we successfully developed a facile one-step method to prepare a GDL with three functional layers by utilizing the different sedimentation rates and filtration rates of short carbon fiber (CF) and carbon nanotube (CNT). The treatment temperature for this GDL is much lower than that of traditional method. The thickness of the GDL can be effectively controlled from as thin as 50 μm to more than 200 μm by simply adjusting the content of CF. The GDL with high flexibility is suitable to develop high performance flexible electronics. The fuel cell with the GDL has the maximum power density 1021 mW cm?2, which shows 19% improvement comparing to the conventional one. Therefore, this work breaks the traditional concept that GDL for fuel cells only can be prepared by very complex and high-cost procedure. 相似文献
4.
以竹浆为原料,结合浆内添加山梨酸钾和表面涂布蜂蜡-纳米TiO2复合物的方法制备了具有自清洁功能的超疏水抗菌纸。利用扫描电子显微镜(SEM)、原子力显微镜(AFM)、X射线光电子能谱(XPS)仪、傅里叶变换红外光谱(FT-IR)仪、抗张/耐折度仪和接触角测定仪对纸张的表面形貌、元素组成、化学结构、力学性能及疏水性能进行了表征。结果表明,所制备的超疏水抗菌纸的抗张指数为89.7 N·m/g,加热处理后其水接触角(WCA)可达152.6°,被酸/碱液浸泡12 h后,其WCA仍能稳定保持在140°以上,具有优异的自清洁特性。抗菌测试结果表明,制得的超疏水抗菌纸对大肠杆菌和金黄色葡萄球菌的抑菌率均达到约100%,说明该超疏水抗菌纸在食品包装用纸领域具有较大的应用潜力。 相似文献
5.
The continuous production of disposable plastic straw places a high demand on global petrochemical resources and a significant environmental burden. Biodegradable and eco-friendly straws have therefore been studied and produced worldwide. This article briefly introduces the characteristics of paper straws and polylactic acid (PLA) straws, and focuses on edible straws made using, e.g., hydrophilic colloids, zein, and starch. Raw-material selection, preparation methods, advantages, and defects of straws are summarized, to provide a reference for the development and research of eco-friendly straws. 相似文献
6.
Improving the Surface Performance of Electrospun Air Filter Paper Using Multi-walled Carbon Nanotubes 下载免费PDF全文
In this study, air filter base paper (P) was used as the receiving substrate, polyvinyl alcohol (PVA) and PVA/multi-walled carbon nanotube (MWCNT) spinning solutions were used to prepare electrospun air filter papers (P-PVA and P-PVA/MWCNT, respectively). Then, P-PVA/MWCNT was calendered under different pressures. The effect of MWCNTs on the surface performance of P-PVA/MWCNT was explored and the influence of calendering technology on their structure and filtration characteristics was analyzed. Electron scanning microscope observation showed that the PVA nanofibers on the surface of P-PVA/MWCNT had no beading, and MWCNTs weakened the surface electrostatic phenomenon and had a good micromorphology. During the calendering process, with an increase in pressure, the mean pore size and surface roughness of P-PVA/MWCNT decreased, the initial resistance increased, and the filtration efficiency changed slightly. 相似文献
7.
采用符合XF 10—2014《消防员灭火防护服》标准的甲纶四层面料与芳纶四层面料,测试其组合的热防护系数(TPP值);用同样的面料制作灭火防护服,并通过假人燃烧实验对比甲纶灭火防护服与芳纶灭火防护服的整体热防护性能。结果表明:甲纶防护服热防护系数不及芳纶灭火防护服,但整体热防护性能远超现行芳纶灭火防护服,甲纶灭火防护服总烧伤面积为15.28%,芳纶灭火防护服总烧伤面积为53.34%。 相似文献
8.
9.
基于数码成像法,利用荧光碳点的高灵敏度结合分子印迹技术的高选择性,建立一种微流控纸芯片法并进行优化,用于金银花绿原酸含量的快速测定。以氮硫掺杂碳点为荧光响应材料,绿原酸为模板分子,在滤纸亲水区表面合成绿原酸印迹聚合物,制得碳点分子印迹纸芯片。以显色斑点的红、绿、蓝值为评价指标进行单因素优化试验。得到最佳制备条件:绿原酸、3-氨丙基三乙氧基硅烷(功能单体)、正硅酸乙酯(交联剂)的物质的量比1∶8∶8,每0.01 mmol绿原酸添加1 mL无水乙醇、0.2 mL氨基修饰的碳点溶液,预聚液超声辅助聚合时间35 min。最佳显色条件:点样量4 μL,显色时间15 min。在最优条件下测定金银花中绿原酸含量,绿原酸质量浓度在0.025~0.15 mg/mL时与绿值有较好的线性关系,决定系数为0.991 8,检出限为0.020 6 mg/mL,回收率在90.77%~102.10%之间。本实验建立的纸芯片法成本低廉、选择性良好且检测速度快(20 min内可完成),可作为测定条件简陋或现场临时快速测定绿原酸含量的补充方法。 相似文献
10.
为进一步扩展聚酰胺6织物的应用领域,采用磺胺作为阻燃整理剂,在高温条件下,通过浸渍沉积法对聚酰胺6织物进行阻燃防熔滴整理。并对整理后聚酰胺6织物的热稳定性、热释放性能、抗熔滴性能、阻燃性能和阻燃机制进行分析。结果表明:经磺胺阻燃整理后,聚酰胺6织物的极限氧指数达到32.2%,损毁长度和损毁面积均减小,无熔滴产生,达到阻燃B1级的要求,具有较好的阻燃效果;同时整理后聚酰胺6织物的最大热释放速率下降了16.9%,火灾危害性显著降低;磺胺主要通过气相阻燃机制提高聚酰胺6织物的阻燃性能,且阻燃整理对聚酰胺6织物的强力和手感影响较小。 相似文献