吉安散装人抗冰战雪保平安——江西吉安散办干部职工铲除冰保畅通纪实

春节前后,吉安市遭遇到罕见的冰冻雨雪灾害天气,连续出现了低温、阴雨和雨夹雪,成为全省灾情最严重地区之一.特别是1月25日以后,出现了持续大范围的雨雪冰冻天气.冰冻损坏了市区的电网,压垮了树枝,封锁了道路和桥梁.     

欧文斯科宁专访

欧文斯科宁公司(以下简称OC)创建66年来一直致力于开发玻璃纤维的新用途,是建筑材料和复合材料行业的领先创新者和制造商,OC进入亚太市场也已超过30年,长久以来他们专注于推广复合材料的应用领域以及扩大其供应基地.最近,欧文斯科宁在印度扩充了生产能力,并在上海设立了技术中心.至今为止,欧文斯科宁在亚太区已有超过1800名员工,从事建筑材料和复合材料的生产,销售和研发工作.     

2010～2011年世界塑料工业进展

收集了2010年7月～2011年6月世界塑料工业的相关资料,介绍了2010～2011年世界塑料工业的发展情况,提供了世界塑料产量、消费量及全球各类树脂的需求量及产能情况。按通用热塑性树脂(聚乙烯、聚丙烯、聚氯乙烯、聚苯乙烯、ABS树脂),工程塑料(尼龙、聚碳酸酯、聚甲醛、热塑性聚酯、聚苯醚),特种工程塑料(聚苯硫醚、液晶聚合物、聚醚醚酮),通用热固性树脂(酚醛、不饱和聚酯树脂、环氧树脂、聚氨酯)不同品种的顺序,对树脂的产量、消费量、供需状况及合成工艺、产品应用开发、树脂品种的延伸及应用的进一步扩展等技术作了详细介绍。     

花粉症诱因探究

花粉症又称季节性鼻炎或枯草热,是敏感个体对花粉的一种超敏反应.在美国,每一百个人当中就有两个以上的人患花粉症;现在日本有1300万人饱受花粉症折磨,超过总人口的10%[1].我国的发病率为0.5%～1%,高发区达到5%,虽没有上述一些国家那么严重,受害者亦相当可观.全世界花粉症发病人数到1999年就已有5000多万[2],可见花粉症患者是一个绝不可轻视的群体.图1显示了花粉过敏症的发病机制.     

酿酒酵母细胞表达异源萜类化合物的研究进展

萜类化合物具有可观的经济价值,但是目前的生产过程复杂、产量低。酿酒酵母甲羟戊酸途径为萜类化合物的合成提供直接前体,因此酿酒酵母细胞具有合成异源萜类化合物的天然优势。对酿酒酵母甲羟戊酸途径的清晰认识是对其进行有效利用的基础,本文从代谢途径、关键酶的特点和全局调控机制3个方面对该途径进行了介绍。从代谢途径的构建和优化、模块与底盘细胞的适配、模块构建及组装方式的角度概述了酿酒酵母细胞异源合成单萜、倍半烯萜、二萜、三萜类化合物的研究进展。指出实现酿酒酵母高效合成萜类化合物所需要解决的基础问题是对酿酒酵母甲羟戊酸途径进行更为全面了解和对萜类化合物的天然代谢途径进行明确解析;另外,合成生物学的进一步发展也将为此提供应用基础。     

喷涂前处理污染源的分析及其处理措施

随着我国国民经济的快速发展和国家"节能减排"重点项目的深入开展,各种污染源的分析及其处理措施的研究备受关注.本文在充分研究若干家电企业的钢铁喷涂制件的前处理工艺(如:预脱脂、脱脂、清洗、表调、磷化等)的基础上,分析喷涂前处理过程中的污染源,研究污染源的处理措施.     

回转窑耐火砖的砌筑及使用

我公司回转窑规格为Φ4.0m×60m.窑内使用的耐火砖为镁铬砖、隔热尖晶石、蓝晶石和黏土砖以及硅莫砖.镁铬砖规格为(81×90×150×200)mm,其它耐火砖规格皆为(81×90×200×200)mm.尽管每个品种的砖品质相同,但由于在镶砌和使用过程中方法不同,寿命有长有短.通过多年实践,现总结如下.     

硅酸钠缓蚀剂的研究现状与展望

硅酸盐资源丰富,无毒,价廉,不繁殖细菌,是一种对环境友好的缓蚀剂.近年来研究的以硅酸盐为主的缓蚀剂复合配方,大大提高了硅酸盐缓蚀剂的应用范围.目前,开发缓蚀剂复合配方已成为一种发展趋势.本文综述了硅酸钠缓蚀剂的应用现状,并对其发展作了展望.     

论啤酒瓶质量与啤酒灌装的协调和统一

为了使啤酒瓶质量与啤酒灌装质量协调统一,探讨了啤酒瓶外形设计、剩余空间和瓶壁厚度与瓶子强度和灌装质量的关系,提出啤酒瓶企业定点向啤酒企业供瓶,两企业协作互动,了解相关的技术、设备性能和工艺流程,以利同步发展.     

化妆品行业如何应对REACH法规

2006年12月7日～2006年12月8日化妆品化学家年会在美国纽约举行,该年会为化学品供应商提供了参与REACH法规的机会.REACH法规的实施引起了业界的广泛关注,来自世界各地的著名化学品及化妆品公司对REACH法规的实施所带来的一些问题,以及新原料、新技术进行了交流.会议主要对就REACH法规、制造及规模化和神经美容品等方面展开了研讨.     

污泥生物炭中氮硫行为及环境效应研究进展

污泥生物炭中氮硫元素含量高,其氮硫行为和环境效应对全球气候变化的影响不容忽视。以往的研究中,研究者往往以富碳生物炭作为主要研究对象,关注碳对全球气候变化的行为和功效,而对氮硫元素的作用关注不够。本文从原始污泥基本性质到其热解过程,再到生物炭的老化,逐步对污泥生物炭整个生命周期内氮硫的行为及其环境效应研究进行综述,并对未来应注重开展的研究方向进行展望,为生物炭中氮硫元素固定、释放及与之关联的环境效应和温室气体排放控制研究提供理论基础。分析表明,污泥中氮元素含量普遍高于硫元素,且热解过程中氮比硫更容易转移至气相产物。氮硫元素随热解温度的增加,在三相产物中的分配都是炭中持续减少,油中先增后减,气中一直增加。高温（＞800℃）条件下,气相中的氮含量高于固相,而硫元素则仍然主要存在于固相中。污泥生物炭老化及其环境效应研究表明,污泥生物炭氮硫元素与土壤的相互作用及其温室效应问题在今后的研究中应引起重视。     

Residual effects of phosphate fertilizers in relation to phosphate sorptivities of 27 soils

Three different parameters of the long term effects of phosphate fertilizers on perennial clover-based pastures were measured over 3–4 years in 27 experiments on acidic soils in an elevated region of eastern Australia. Recovery of fertilizer P was the difference between herbage P uptake in the presence of fertilizer and uptake in its absence, expressed as a % of the amount of P applied in the first year. Residual value was the size of the response to fertilizer P, applied in the first year, expressed as a percentage of the response to freshly applied P in the second and third years. Effectiveness was the product of the values of the Mitscherlich curvature and response parameters for each response curve, and residual effectiveness was relative to initial effectiveness. Soils varied widely in their P sorptivities, and represented Alfisols, Entisols, and Ultisols of basaltic, granitic and sedimentary origin. Mean P recoveries of 29% in the first year and 49% over 3 years, residual values of 84% in the second year and 60% in the third, and residual effectiveness of 77% in the second year and 47% in the third were high by most standards. Increasing P sorptivity tended to increase fertilizer effectiveness in the first year and residual value in the second year, but it depressed P recovery in the first year and residual effectiveness in later years. The long term effect of increasing P sorptivity on cumulative P recoveries tended to be negative at low to medium rates of fertilizer application and positive at high rates of application. There was a much smaller decline in residual values and effectiveness over the 3 or 4 years than there was in P recovery, and this was attributed to the beneficial effects of P on soil N fertility, via clover N fixation, and the subsequent growth of grasses in the phosphated treatments.     

Changes in the Properties of Synthetic Fibres in Thermal Aging

Thermal aging of complex lavsan, nitron, and anid fibres and lavsan and nitron yarn was investigated in the temperature region above the glass transition temperature (120, 150, 180°C) in the free state and with shrinkage for up to 300 h. It was shown that thermal aging of chemical fibres in the general case includes periods of structural and thermochemical aging. The kinetic characteristics of thermal shrinkage of chemical fibres and yarn in the first period of thermal aging were investigated. An exponential curve of shrinkage in time was obtained and can be used to predict the behavior of fibres and yarn in the first period of aging in the free state. The kinetics of the change in the strength and relative elongation at break was investigated in prolonged thermal aging of chemical fibres and yarn in the free (with shrinkage) and fixed (without shrinkage) states. The exponential dependence of the change in the fibre breaking characteristics on the duration of heat treatment was demonstrated. The change in the properties in prolonged thermal aging in the free and fixed states in the first stage of aging takes place differently. With shrinkage, the strength decreases and the deformability increases as a result of relaxation phenomena in the first stage, followed by a symbatic decrease in the strength and deformability as a result of thermal degradation processes in the second stage. In heat treatment in the fixed state, the change in the mechanical properties in the first stage is slight, while the strength and deformability simultaneously decrease in time as a result of thermal aging in the second stage. The quantitative characteristics found can be used to predict the change in the mechanical properties of chemical fibres and yarn in conditions of prolonged exposure to heat.     

Solubility in and affinity for the bile salt micelle of plant sterols are important determinants of their intestinal absorption in rats

Intestinal absorption of various plant sterols was investigated in thoracic duct-cannulated normal rats. Lymphatic recovery was the highest in campesterol, intermediate in brassicasterol and sitosterol, and the lowest in stigmasterol and sitostanol. Higher solubility in the bile salt micelle was observed in sitosterol, campesterol, and sitostanol than in brassicasterol and stigmasterol. The solubility of the latter two sterols was extremely low. When the affinity of plant sterols for the bile salt micelle was compared in an in vitro model system, which assessed sterol transfer from the micellar to the oil phase, the transfer rate was the highest in brassicasterol, intermediate in campesterol and stigmasterol, and lowest in sitosterol and sitostanol. Although no significant correlations between lymphatic recovery of plant sterols and their micellar solubility or transfer rate from the bile salt micelle were observed, highly positive correlation was obtained between the lymphatic recovery and the multiplication value of the micellar solubility and the transfer rate. These observations strongly suggest that both solubility in and affinity for the bile salt micelle of plant sterols are important determinants of their intestinal absorption in rats.     

Streptozotocin-Induced Diabetes Causes Changes in Serotonin-Positive Neurons in the Small Intestine in Pig Model

Serotonin (5-hydroxytryptamine or 5-HT) is an important neurotransmitter of the central and peripheral nervous systems, predominantly secreted in the gastrointestinal tract, especially in the gut. 5-HT is a crucial enteric signaling molecule and is well known for playing a key role in sensory-motor and secretory functions in the gut. Gastroenteropathy is one of the most clinical problems in diabetic patients with frequent episodes of hyperglycemia. Changes in 5-HT expression may mediate gastrointestinal tract disturbances seen in diabetes, such as nausea and diarrhea. Based on the double immunohistochemical staining, this study determined the variability in the population of 5-HT-positive neurons in the porcine small intestinal enteric neurons in the course of streptozotocin-induced diabetes. The results show changes in the number of 5-HT-positive neurons in the examined intestinal sections. The greatest changes were observed in the jejunum, particularly within the myenteric plexus. In the ileum, both de novo 5-HT synthesis in the inner submucosal plexus neurons and an increase in the number of neurons in the outer submucosal plexus were noted. The changes observed in the duodenum were also increasing in nature. The results of the current study confirm the previous observations concerning the involvement of 5-HT in inflammatory processes, and an increase in the number of 5-HT -positive neurons may also be a result of increased concentration of the 5-HT in the gastrointestinal tract wall and affects the motor and secretory processes, which are particularly intense in the small intestines.     

Intake of dietary fiber in the Central American isthmus: nutritional implications

Mean intakes of dietary fiber (DF) were estimated in the population of Central America and Panama, using the results of dietary surveys conducted in 1969 and 1986 both in rural and urban areas, as well as data on the DF content of foods as consumed in the region. Data on preschool children were also estimated. The results indicated that DF intake in urban areas is lower than that of rural areas, particularly in Costa Rica and Panama. In 1969, intake varied from 32g in El Salvador to 15g in Panama in urban areas, while in rural areas intake was from 45g in El Salvador to 13g in Panama. The foods which contributed most to the total intake in Guatemala, El Salvador and Honduras were tortillas and beans, while in Costa Rica and Panama, beans provided the largest intake. In preeschool children, intake was 12.5g in El Salvador and 5.4g in Costa Rica in 1969, which is the same tendency as that found for adults. From more recent data on food intake, it was found that DF intake had decreased in the rural areas of El Salvador, Honduras and Costa Rica, being between 4 and 9% in the first two countries and 12% in Costa Rica. In the urban area of the latter, from 1969 to 1986 a decrease in DF intake of around 20% has taken place.     

Possible Role of Crystal-Bearing Cells in Tomato Fertility and Formation of Seedless Fruits

Crystal-bearing cells or idioblasts, which deposit calcium oxalate, are located in various tissues and organs of many plant species. The functional significance of their formation is currently unclear. Idioblasts in the leaf parenchyma and the development of crystal-bearing cells in the anther tissues of transgenic tomato plants (Solanum lycopersicon L.), expressing the heterologous FeSOD gene and which showed a decrease in fertility, were studied by transmission and scanning electron microscopy. The amount of calcium oxalate crystals was found to increase significantly in the transgenic plants compared to the wild type (WT) ones in idioblasts and crystal-bearing cells of the upper part of the anther. At the same time, changes in the size and shape of the crystals and their location in anther organs were noted. It seems that the interruption in the break of the anther stomium in transgenic plants was associated with the formation and cell death regulation of a specialized group of crystal-bearing cells. This disturbance caused an increase in the pool of these cells and their localization in the upper part of the anther, where rupture is initiated. Perturbations were also noted in the lower part of the anther in transgenic plants, where the amount of calcium oxalate crystals in crystal-bearing cells was reduced that was accompanied by disturbances in the morphology of pollen grains. Thus, the induction of the formation of crystal-bearing cells and calcium oxalate crystals can have multidirectional effects, contributing to the regulation of oxalate metabolism in the generative and vegetative organs and preventing fertility when the ROS balance changes, in particular, during oxidative stresses accompanying most abiotic and biotic environmental factors.     

Mesoscopic modeling of two-phase behavior and flooding phenomena in polymer electrolyte fuel cells

A key performance limitation in polymer electrolyte fuel cells (PEFC), manifested in terms of mass transport loss, originates from liquid water transport and resulting flooding phenomena in the constituent components. Liquid water covers the electrochemically active sites in the catalyst layer (CL) rendering reduced catalytic activity and blocks the available pore space in the porous CL and fibrous gas diffusion layer (GDL) resulting in hindered oxygen transport to the active reaction sites. The cathode CL and the GDL play a major role in the mass transport loss and hence in the water management of a PEFC. In this work the development of a mesoscopic modeling formalism coupled with realistic microstructural delineation is presented to study the influence of the pore structure and surface wettability on liquid water transport and interfacial dynamics in the PEFC catalyst layer and gas diffusion layer. The two-phase regime transition phenomenon in the capillary dominated transport in the CL and the influence of the mixed wetting characteristics on the flooding dynamics in the GDL are highlighted.     

Sp7 Transgenic Mice with a Markedly Impaired Lacunocanalicular Network Induced Sost and Reduced Bone Mass by Unloading

The relationship of lacunocanalicular network structure and mechanoresponse has not been well studied. The lacunocanalicular structures differed in the compression and tension sides, in the regions, and in genders in wild-type femoral cortical bone. The overexpression of Sp7 in osteoblasts resulted in thin and porous cortical bone with increased osteoclasts and apoptotic osteocytes, and the number of canaliculi was half of that in the wild-type mice, leading to a markedly impaired lacunocanalicular network. To investigate the response to unloading, we performed tail suspension. Unloading reduced trabecular and cortical bone in the Sp7 transgenic mice due to reduced bone formation. Sost-positive osteocytes increased by unloading on the compression side, but not on the tension side of cortical bone in the wild-type femurs. However, these differential responses were lost in the Sp7 transgenic femurs. Serum Sost increased in the Sp7 transgenic mice, but not in the wild-type mice. Unloading reduced the Col1a1 and Bglap/Bglap2 expression in the Sp7 transgenic mice but not the wild-type mice. Thus, Sp7 transgenic mice with the impaired lacunocanalicular network induced Sost expression by unloading but lost the differential regulation in the compression and tension sides, and the mice failed to restore bone formation during unloading, implicating the relationship of lacunocanalicular network structure and the regulation of bone formation in mechanoresponse.     

我国粮食主产区尿素供需时空特征及市场调控思路

在总结前人研究的基础上,重点从季节和作物角度对我国粮食主产区尿素供需状况作了深入分析。研究结果表明,我国粮食主产区尿素全年的总体供应量大于需求量,但季节间和区域间供需却不平衡。3月和7月是尿素消费高峰期,易发生供应不足,而尿素消费和生产区域分布不一致导致消费旺季供需矛盾更加突出,是导致价格波动和运输困难的主要原因。针对尿素供需矛盾,对我国化肥产业的宏观调控策略提出了一些想法,以期为我国化肥产业和农业的健康稳定发展提供依据。