密度叠印率与色差之间关系的研究

目的 研究密度叠印率与其叠印色差的关系, 并尝试确定密度叠印率合格标准。方法 理论推导求解网点百分比叠印率与叠印色差的量化关系, 理论推导网点百分比叠印率与贝雷斯叠印率的量化关系,并通过Excel进行数据分析与计算。结果 当第2色实地密度为1.5时, M/Y, C/Y, C/M的贝雷斯叠印率合格标准分别大于或等于70%, 73%, 86%。结论 网点百分比叠印率与色差呈近似线性反比关系, 密度叠印率受多种因素影响, 叠印率合格标准仅在特定条件下有效。     

PostScript印刷测控条的开发与应用

根据制版和印刷质量控制理论,从使用测控条的目的和意义入手,采用PostScript语言编写出一种既能控制传统印刷过程,又能控制数字印刷质量的彩色数字印刷测控条.用测控条中的相应结构可监控印刷品的实地密度、网点增大、印刷反差、叠印情况、网点滑动或重影等印刷性能要求.     

CTP印刷质量控制参数测试与分析

阐述了实地密度、网点扩大、相对反差、叠印率4个参数在印刷质量控制中的意义,设计并印刷了CTP测试版样张,对随机抽样的22张样张的4个参数作了测试与计算,用数据信息表达了CTP印刷品质量状况,供CTP印刷相关人员学习和参考.     

铜版纸与哑粉纸印刷复制特性研究

采用实验方法,对铜版纸和哑粉纸的印刷复制特性进行了测试和比较。 结果显示,2 种纸张的最佳印刷反差和实地密度略有差异;在相同的印刷条件下,与铜版纸相比,哑粉纸印刷品相对反差大,网点扩大小,叠印率、颜色亮度、总油墨覆盖率高,色差小,但颜色饱和度低,局部范围色域较小。 为了获得最佳的印刷效果,应该采用不同的印刷参数,适当增加哑粉纸的用墨量。     

数码印刷产品质量分析与控制

针对DC2060 数码印刷机模拟SWOP 的色彩设置,获得数码印刷样品的实地密度、相对反差、网点增大及叠印等参数.对四色数码印刷曲线进行三阶多项式处理,并将参数与胶印产品的质量参数进行了对比分析.提出对环境条件、耗材、最大密度和输出曲线等控制以获得高质量的数码印刷品.     

基于密度的凹版专色叠印色光谱预测模型的研究及应用

目的 建立一种基于密度与光谱反射率关系的专色叠印色光谱预测模型。方法 首先建立前景色、后景色密度与其光谱反射率关系;基于此建立叠印色光谱反射率的计算方法;其次对模型进行优化,完成专色叠印色光谱预测模型的建立;再通过凹版印刷实打样30张专色叠印色样张,基于Malab利用色差以及拟合决定系数R²对预测模型进行验证;最后在相同工艺条件下实打样专色叠印色样张进行预测,通过色差完成对模型的精度检验。结果 验证表明,不同专色叠印色在同一网点面积率下与其对应的前景色、后景色密度之间存在较强相关关系,其拟合决定系数R²均大于0.9;模型精度检验中,73.7%的模型预测值与样张实测值色差为0~2.5个CIE1976色差单位,大部分色块色差为0~2个CIE1976色差单位,占总频率的60.54%,整体平均色差为1.92个CIE1976色差单位。结论 本文所建模型具有较高的预测精度,能基本满足对颜色预测的需求。     

数字印刷测试版的设计与应用研究

进入21世纪以来,数字印刷以其快速、高效、灵活、可变数据印刷的特点,具有广泛的应用领域。但由于数字印刷的作业特点,用于传统印刷的控制条无法作为其制版、印刷质量检验与控制的手段。为了实现印刷的数据化、规范化及标准化控制,我们必须设计出既能控制印刷过程又能控制印刷品质量的数字印刷测试版。从使用测控条目的和意义入手,本文采用PostScript语言编写出一种既能控制传统印刷过程,又能控制数字印刷质量的测控条,组合并输出为PS或EPS文件,把生成的PostScript数字印刷测控条与一般的质量控制元素如色彩再现等元素组合成数字印刷测试版,用于监控印刷过程,分析印刷品质量问题,实现对实地密度、网点扩大、印刷反差、阶调再现、叠印率、网点变形、重影、分辨率、印刷灰平衡等技术参数的控制。     

马口铁印刷中影响印刷反差(K值)的几大因素

印刷反差（K值）是评价印刷品质量的最重要指标,它是实地密度和网线密度之差和实地密度的比值,通常选取网点面积为75％的网点实地密度。它主要表现在印刷品的层次上,印刷反差越高,印刷品层次拉得越开,给人视觉上的冲击越大,反之,则使得印刷品层次并级,无精神,色偏,给人眼的感觉很不好。那我们怎样才能把它控制好呢？     

网点形状对胶印网点复制特性的影响

研究了胶印工艺中方形、圆形、圆方形网点在相同条件下的印版网点复制特性、印品网点复制特性和颜色复制特性,比较了3种网点在实地密度值、叠印率、印刷反差、网点增大、色域、饱和度等影响印刷质量的关键技术参数上的差异,提出了有利于印品阶调和色彩复制的网点形状选择依据,得出了对印刷过程具有一定的实际指导意义的结论。     

纸张数字印刷工艺及质量的研究

设计了数字印刷原稿,通过改变数字印刷的参数得到印刷样张,从实地密度、相对反差、叠印率、网点增大等方面,研究油墨浓度、激光强度两个因素对印刷质量的影响。油墨浓度和激光强度对印刷质量的影响曲线,为数码印刷工艺的进一步研究提供理论和实践依据。     

The Research of Anti-Wear Properties of Organomolybdenum Compounds in the Engine Oils

A four-ball tester was used to evaluate the anti-wear performance of three kinds of organomolybdemun compounds in the engine oils, i. e., molybdenum dialkyldithiophosphate (MoDDP), molybdenum dialkyldithiocarbamate ( MoDTC), and sulphur and phosphorus freeorganomolybdeum (Molybdate). The results indicate that a low concentration of MoDDP doesn' t improve the anti-wear properties of the commercial engine oils, but a high concentration of MoDDP can obviously improve the anti-wear properties and the load-carrying capacity of the engine oils. MoDTC doesn' t improve the antiwear properties of the engine oils, but worsens the anti-wear properties of the oils. Signifi can timprove ment of frictional and wear characteristics is obtained with Molybdate added in the commercial engine oils and the formulated oils.     

Certification Becomes Important for the I Quality; and Safety Supervision of the Chinese Liquor Sector

The end of 2007, over 200 unit products of more than 80 Chinese firms have passed the quality grade certification for liquor products. These products involve distilled spirits, beer, wine, yellow wine, fruit syrup wine and others, and cover over 80% of the national top-branded liquor products.……     

Deposition and Coating Properties on CVD Tungsten

Surface characterization and microstructure studies are performed on chemical vapor deposited (CVD) tungsten coating. There is about 2 μm thickness diffusion layer of tungsten in the molybdenum substrate. The thermal shock test shows tungsten coating has good adhesion with molybdenum substrate, but the elements of oxygen and carbon in the tungsten coating have the bad affection to the adhesion. The result of high-temperature diffusion experiment is the diffusion rate from molybdenum substrate to tungsten coating is faster.     

Analysis of marine hydrobiont lipid extracts as possible cryoprotective agents

We studied a combined effect of the cryoprotectants both of lipid and carbohydrate origin at the presence of DMSO or without it on cell viability and the RNA synthesis in the embryonic mollusc and echinoderm cell cultures obtained at different developmental stages. Cryoprotective properties of exogenous lipids correlated with their thermotropic behavior. Lipid extracts from marine hydrobiontes, which thermal transitions are characterized by relatively small part of calorimetric thermogram area lying at temperatures above 0 °C (6–18%), were found to possess a considerable cryoprotective activity. The results are discussed in relation to the prediction of the cryoprotective activity of lipid extracts for marine animal cells. In addition, it was found that marine invertebrate cells can be cryopreserved without DMSO at the presence of trehalose and lipid extracts of some marine hydrobiontes.     

Low-Temperature Properties of Silver

Pure silver is used extensively in the preparation of high-temperature superconductor wires, tapes, films, and other configurations in which the silver not only shields the superconducting material from the surrounding materials, but also provides a degree of flexibility and strain relief, as well as stabilization and low-resistance electrical contact. Silver is relatively expensive, but at this stage of superconductor development, its unique combination of properties seems to offer the only reasonable means of achieving usable lengths of conductor. In this role, the low-temperature physical (electrical, thermal, magnetic, optical) and mechanical properties of the silver all become important. Here we present a collection of properties data extracted from the cryogenic literature and, to the extent possible, selected for reliability.     

Early ironwork in Biscay: Survey,excavation, experimentation and materials characterization. An integral study of the mountainside ironworks (ferrerías de monte or “haizeolak”)

ABSTRACT

The production of iron in Biscay (Basque Country, Spain) has been a hallmark of this territory of the North of the Iberian Peninsula throughout its history. The Archaeology team of the Basque Country Mining Museum has spent 13 years, so far, studying the origins of this activity through the evidences left at the old pre-hydraulic iron production workshops known as mountainside ironworks (ferrerías de monte) or haizeolak. It has catalogued 170 archaeometallurgical sites of this type in Biscay, and the archeological excavation of some of them has led to the knowledge of the different stages of the production process that took place in these workshops. The team has also experimentally reproduced the work carried out in a mountainside ironworks from the High Middle Ages, and it has currently started the characterization process of this type of activity through the study of the collected materials.     

Mechanism Study on the Wear of CrAlTiN Coated High-Speed Steel Twist Drills Under Dry Cutting Conditions

As demands about environment protection are growing up, dry cutting technology is getting more and more concerns from all over the world. Main works performed here are study on dry cutting performances and wear mechanisms of M2high-speed steel (HSS) twist drills with CrAlTiN multicomponent coatings, which was deposited using magnetron sputter ion plating system, in drilling 45 and 30CrMnSiA steel, and their comparisons to those in drilling the same steel but using monolayer CrN and commercial TiN coated drills. Drilling performances of drills are evaluated mainly through the measurements of width on outer corner flank land and the cutting forces. Results show that performances of CrAlTiN coated drills are better than those of monolayer CrN and TiN coated drills. In drilling 45 and 30CrMnSiA steel, the average tool life of the CrAlTiN coated drills are 17.2 and 11.8 times higher than those of the uncoated drills. Observing wear of the drill with scanning electronic microscope, results show that there is no crack or spallation of the CrAlTiN coatings in wear zones. Main mechanism of the wear here is adhesion.     

Study on Bond Ability of Arc-Spraying Coatings with Different Surface Pretreatment on Cast-Iron

Arc spraying coatings are widely used in various applications, but uncommon in cast iron substrate. Different surface pretreatment technology is tested on substrates of gray cast iron. Surface roughness and residual stress were measured by TR200 and X-ray diffraction analyzer. Influence of different surface pretreatment methods ( dry blasting and fusebond) on roughness and residual stress was analyzed. The arc-sprayed coatings of wire 3Cr13 (φ2mm) on gray cast iron substrate is studied. The microstructure and interface of bonding layer were observed by SEM. The bond strength was taken by tensile test. Results show that bond strength with grit blasting is higher than fuse-bond; it is feasible to make wire 3Cr13 coating with arc spraying on cast iron substrate roughened by grit blasting.     

Structural Characteristics of TiO2 Ceramic Coating by Micro-Plasma Oxidation

TiO2 ceramic coatings with thickness of 20 μm were formed on the surface of pure titanium by micro-plasma oxidation. Their micro-structures were investigated by by using X-ray diffraction and their surface images were detected by using scan electronic microscope. There were three kinds of TiO2 coatings, pure anatase type TiO2 phase, mixed phases consisted of rutile type TiO2 phase and anatase type TiO2 phase, pure rutile type TiO2 phase. The coating surface with the pure anatase type TiO2 phase is rough, while the coating surface with the pure rutile type TiO2phase is smooth. The upper coating surface with the mixed type TiO2 phases is anatase type TiO2 structure and the subsurface of the TiO2 coating is rutile type TiO2structure.     

Evaluation of fatigue life of steel using steel grain size

The insightful discussion of the relationship between the construction of metallographic and fatigue life and proposition of mathematical relationships describing this relationship was conducted in the paper. This paper presents a method for estimating the fatigue life, based on the construction of the microstructural material taking into account the grain size and the participation of ferrite and pearlite phase.