湘潭四桥钢结构涂装工艺及质量控制

文章介绍了湘潭四桥钢结构的涂装配套和工艺,并结合实际施工介绍了桥梁钢结构涂装的施工质量控制标准和方法。湘潭四桥钢结构涂装工程为典型的内陆工业大气环境下钢结构涂装防腐工程,文章通过对涂装工艺及质量控制的介绍．为类似桥梁钢结构防腐涂装提供借签。     

节能环保涂装新工艺、新设备及新材料在汽车涂装中的应用

建设资源节约型、环境友好型的涂装生产线是汽车制造业所必须重点考虑的课题,涂装车间高效节能设备及新工艺随之应运而生。本文主要介绍了目前国际上流行的节能环保涂装新工艺、新设备及新材料在汽车涂装的应用,并简单介绍了节能环保涂装工艺的现场操作。     

阴极电泳涂装中漆膜常见的问题及解决措施

介绍了电泳涂装的优缺点,阴极电泳涂装的基本原理和工艺流程,重点介绍了阴极电泳涂装过程中漆膜常见的问题及解决措施.     

汽车涂装中的节能环保新工艺

主要介绍节能环保涂装新工艺、新设备及新材料在汽车涂装的应用,简单介绍了节能环保涂装工艺的现场操作。     

塑料涂装

从塑料结构入手，介绍了塑料涂装的特点、塑料用涂料的性能要求及涂料的选择，介绍了塑料制品涂装前的表面处理及涂装工艺设计。     

中国汽车涂装生产线新技术的应用及发展

介绍了国内汽车涂料、涂装工艺、涂装设备及涂装管理的最新应用发展。     

我国汽车涂装的现况及发展趋向

文章在介绍我国汽车工业及涂装行业现况的基础上,论述了汽车涂装的发展趋势、拟选用的最新涂装技术及建议.     

智能电视头的装饰性防护涂装

介绍了智能电视头涂装的要求。确定与评价了其装饰性防护涂装体系及工艺,并讨论了涂装过程中出现的问题及解决方法。     

涂装滑橇输送系统柔性化研究与探讨

介绍了涂装车间的滑橇输送系统,研究了涂装滑橇输送系统柔性化生产的关键技术,并着重介绍了汽车涂装滑橇输送系统柔性化的主要途径及方式特点、应用场合,通过对比分析,为汽车涂装车间的工程设计、柔性化、智能化拓展了思路。     

汽车备件与商品车混线生产的涂装材料管理探讨

介绍了汽车备件的分类、特点及涂装工艺,分析了自制备件涂装中常见的问题及应对措施,讨论了涂装材料的结算方式。     

Mechanisms Governing Anaphylaxis: Inflammatory Cells,Mediators, Endothelial Gap Junctions and Beyond

Anaphylaxis is a severe, acute, life-threatening multisystem allergic reaction resulting from the release of a plethora of mediators from mast cells culminating in serious respiratory, cardiovascular and mucocutaneous manifestations that can be fatal. Medications, foods, latex, exercise, hormones (progesterone), and clonal mast cell disorders may be responsible. More recently, novel syndromes such as delayed reactions to red meat and hereditary alpha tryptasemia have been described. Anaphylaxis manifests as sudden onset urticaria, pruritus, flushing, erythema, angioedema (lips, tongue, airways, periphery), myocardial dysfunction (hypovolemia, distributive or mixed shock and arrhythmias), rhinitis, wheezing and stridor. Vomiting, diarrhea, scrotal edema, uterine cramps, vaginal bleeding, urinary incontinence, dizziness, seizures, confusion, and syncope may occur. The traditional (or classical) pathway is mediated via T cells, Th2 cytokines (such as IL-4 and 5), B cell production of IgE and subsequent crosslinking of the high affinity IgE receptor (FcεRI) on mast cells and basophils by IgE-antigen complexes, culminating in mast cell and basophil degranulation. Degranulation results in the release of preformed mediators (histamine, heparin, tryptase, chymase, carboxypeptidase, cathepsin G and tumor necrosis factor alpha (TNF-α), and of de novo synthesized ones such as lipid mediators (cysteinyl leukotrienes), platelet activating factor (PAF), cytokines and growth factors such as vascular endothelial growth factor (VEGF). Of these, histamine, tryptase, cathepsin G, TNF-α, LTC₄, PAF and VEGF can increase vascular permeability. Recent data suggest that mast cell-derived histamine and PAF can activate nitric oxide production from endothelium and set into motion a signaling cascade that leads to dilatation of blood vessels and dysfunction of the endothelial barrier. The latter, characterized by the opening of adherens junctions, leads to increased capillary permeability and fluid extravasation. These changes contribute to airway edema, hypovolemia, and distributive shock, with potentially fatal consequences. In this review, besides mechanisms (endotypes) underlying IgE-mediated anaphylaxis, we also provide a brief overview of IgG-, complement-, contact system-, cytokine- and mast cell-mediated reactions that can result in phenotypes resembling IgE-mediated anaphylaxis. Such classifications can lead the way to precision medicine approaches to the management of this complex disease.     

Hydrocarbon components of the yellowheaded spruce sawfly sex pheromone

The primary sex pheromone of the yellowheaded spruce sawfly,Pikonema alaskensis (Rohwer) (Hymenoptera: Tenthredinidae), was found to include a series of straight-chain hydrocarbon dienes, all with the double bonds in the 9 and 19 positions and all with the (Z, Z) configuration. The major components, of 29, 31, 33, 35, and 37 carbon atoms, were synthesized. In the field and the greenhouse, the synthetic dienes were far above control levels in activity but, at least during the first hours of bioassay, were somewhat less active than the female-derived materials on a weight basis. In the field, a mixture of all five synthetic dienes, in the proportions found in the females, was more attractive than any single one, on a mole basis. In addition, (Z, Z)-9,19 dienes of 28, 30, 32, 34, 36, 38, and 39 carbons have been detected in females in minor amounts. The first five were bioassayed, and each was found to be similar in activity to the 35-carbon component when compared on a weight basis. The synthetic dienes, while active by themselves, were strongly synergized by two, more polar, Florisil fractions derived from females. Experimental design considerations are discussed.     

Organokines in Rheumatoid Arthritis: A Critical Review

Rheumatoid arthritis (RA) is a systemic autoimmune disease that primarily affects the joints. Organokines can produce beneficial or harmful effects in this condition. Among RA patients, organokines have been associated with increased inflammation and cartilage degradation due to augmented cytokines and metalloproteinases production, respectively. This study aimed to perform a review to investigate the role of adipokines, osteokines, myokines, and hepatokines on RA progression. PubMed, Embase, Google Scholar, and Cochrane were searched, and 18 studies were selected, comprising more than 17,000 RA patients. Changes in the pattern of organokines secretion were identified, and these could directly or indirectly contribute to aggravating RA, promoting articular alterations, and predicting the disease activity. In addition, organokines have been implicated in higher radiographic damage, immune dysregulation, and angiogenesis. These can also act as RA potent regulators of cells proliferation, differentiation, and apoptosis, controlling osteoclasts, chondrocytes, and fibroblasts as well as immune cells chemotaxis to RA sites. Although much is already known, much more is still unknown, principally about the roles of organokines in the occurrence of RA extra-articular manifestations.     

Field evidence of synergism and inhibition in the sesiidae sex pheromone system

The E,Z, Z,Z, and Z,E geometric isomers of 3,13 octadecadien-1-ol acetate were used singly and in binary combinations to trap sesiids in Wisconsin cherry orchards. The Z,E isomer alone did not capture any sesiids. A synergistic effect, however, of Z,E onSynanthedon pictipes response to its pheromone E,Z was demonstrated for the first time. Strong inhibitory effects of the Z,Z isomer onS. pictipes response to E,Z, and of the E,Z isomer onS. scitula response to Z,Z, were found. As little as 0.5% of Z,Z in E,Z completely inhibited theS. pictipes response. This species' response was also reduced by 85% when Z,Z was evaporated at 4 points, each ca. 6 m from the pheromone trap. Consistencies and discrepancies of the data with relevant experimental results from other geographical areas are briefly discussed.Lepidoptera: Sesiidae (=Aegeriidae), the clearwing moths.Research supported by the College of Agriculture and Life Sciences, University of Wisconsin, Madison, and by the Wisconsin Red Tart Cherry Ind. Market. Order.     

Soil nutrient depletion by agricultural production in Southern Mali

The degree of soil mining by agricultural production in Southern Mali is assessed by calculating nutrient balances: differences between the amount of plant nutrients exported from the cultivated fields, and those added to the fields. Export processes include extraction by crops, losses due to leaching, to erosion, and to volatilization and denitrification. Inputs include applications of fertilizer and manure, restitution of crop residues, nitrogen fixation, atmospheric deposition of nutrients in rain and dust, and enrichment by weathering of soil minerals. Nutrient balances are calculated for N, P, K, Ca, and Mg. Both pessimistic and optimistic estimates are given.The resulting figures indicate, even when the most optimistic estimates are used, large deficits for nitrogen, potassium and magnesium. For the region as a whole, the calculated deficits are -25 kg N/ha,-20 kg K/ha, and -5 kg Mg/ha. Further, acidification is to be expected, in particular in areas where cotton is grown. The deficits are caused by traditional cereal crops, but also by cotton and especially by groundnut. The latter two crops are fertilized, but insufficiently. It is important to note, that the negative figures are not automatic recommendations for application of a specific amount of additional fertilizer. For phosphorus and calcium the balance of the region as a whole appears to be about in equilibrium, but locally large variations may occur.Erosion and denitrification are important causes of nutrient loss, accounting respectively for 17 and 22% of total nitrogen exports. Atmospheric deposition and weathering of minerals in the soil are still important nutrient inputs that contribute as much as nutrients as organic and mineral fertilizer combined. Nutrient depletion is very large in comparison to the amount of fertilizer applied. Drastic options, such as doubling the application of fertilizer or manure, or halving erosion losses, even if feasible, would still not be enough to make up for the calculated deficits.The annual value of withdrawn nutrients, if related to prices of fertilizers, varies between 10,000 and 15,000 FCFA/ha (40-60 US $/ha). Since the estimated average gross margin from farming in this area is 34,000 FCFA/ha (123 US $/ha), soil mining appears to provide an amount equal to 40% of farmers' total income from agricultural activities.     

微波消解-石墨炉原子吸收法测定唇膏中4种金属的含量

唇膏经微波消解,石墨炉原子吸收光谱法测定样品中铅、锰、铬、镉的含量。在优化的仪器工作条件下,质量浓度分别在32.0、8.0、8.0、8.0 mg/L范围内呈良好的线性关系,检出限分别为4.2、3.5、2.3、2.5μg/L,测得回收率在98%~103%之间,精密度分别为4.1%、3.6%、3.9%、2.7%。     

陶瓷名物探源二则

匋、陶、窑(窯)上古皆读成舌头音,意义又相通,实际为一个意义上先后产生的几个形体不同的字,先民以陶(匋)既称呼窑灶,又指窑灶出品之物,又指制作陶器;坏(坯)、瓶、瓬、瓿、甂、缶、钵、皿、杯(盃)、盆(瓫)均指窑灶所出之物或后世模仿窑灶出品之物,其字皆由重唇音演变而来,亦为同胞兄弟的同源词。     

典型过程强化技术在纳米材料制备中的应用进展

纳米材料被誉为21世纪的新材料,广泛应用于化工、电子、国防、陶瓷等领域.传统的纳米材料制备方法面临粒径控制较困难、批次间重复性差,存在放大效应等不足.过程强化技术是化学工程学科的研究前沿和热点方向之一,旨在通过在生产过程中采用新工艺、新设备等手段,实现缩减操作单元、减小设备体积、提高生产能力及能量利用效率的目的,是实现...     

木质素纳米颗粒的制备及其功能化应用研究进展

木质素是一种天然生物质资源,来源广泛,成本低廉。近年来,利用纳米技术将木质素制备成木质素功能化纳米颗粒极大推动了木质素的利用,同时显著解决了传统材料无法解决的突出问题。详细介绍了木质素功能化纳米颗粒的自组装法、机械法、聚合组装法、冻干炭化法等制备方法及其在催化剂、助剂、吸附剂、紫外防护和抗氧化、抗菌、载体材料、聚集诱导发光材料等领域的应用研究,展望了木质素纳米颗粒的应用前景。指出实现木质素纳米颗粒的可控制备、功能化修饰,将有利于推动木质素功能化纳米颗粒在环保、能源、催化和生物医学等领域的进一步应用。     

明胶分子量分布测定和表征的研究进展(二)

<正> 6.SDS—PAGE(十二烷基硫酸钠-聚丙烯 酰胺凝胶电泳)法 从1959年Raymond和1964年Davis用聚丙烯酰胺凝胶分离人血清蛋白成功后,聚丙烯酰胺凝胶电泳得到了广泛的发展,成为分离、分析蛋白质、核酸类生物