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1.
《聚氨酯》2014,(8)
正一、市场行情简述本月行情:本月纯MDI市场弱势向下,月初开盘,万华公布结算及挂牌,但下游对于万华挂牌结算反馈平平,按需采购,采购意向一般,持货商心态不稳,积极出货,随后,淡季需求明显萎缩,需求利空依旧延续,贸易商减仓避险,让利走货,中旬,夏季高温来临,受到限电等影响,下游生产积极性不高,且场内利好难寻,商谈重心小幅下挫,临近月末,随着万华公布本月挂牌与结算,与上月持稳,超过市场预期,下游反馈平平,成交重心持续低  相似文献   

2.
《聚氨酯》2014,(8)
正一、市场行情简述本月行情:7月,国内TDI市场报盘行情上行。月初,受7月高挂牌影响,持货商坚挺报价,然市场需求寡淡,持货商存出货压力,报盘相对平稳。月中,受巴斯夫高结算消息支撑,持货商挺市意向明显,报盘向上引导市场,然传统淡季,下游抵触情绪明显,场内货源充足,挺市不易,多数交投僵持。月末,TDI工厂8月挂牌结算出台,高结算超出预期,工厂挺市心态明显,持货商心态消极,报盘调涨,场内低价货源逐渐消失,然下游抵触高价,多有价无市,实质性交投寥寥。下游需求跟进不足,预计TDI市  相似文献   

3.
正本发明涉及一种氢溴酸普拉格雷醋酸化合物的合成方法。以普拉格雷为中间体,将普拉格雷和水混合搅拌,得悬浊液,然后与氢溴酸和醋酸反应,加入有机溶剂,析出固体,干燥,即得,或者,以氢溴酸普拉格雷为中间体,将氢溴酸普拉格雷和水混合搅拌,得悬浊液,然后和醋酸反应,加入有机溶剂,析出固体,干燥,即得。本发明采用水作为溶剂,更加环保,节能,而且本发明步骤简单,得到的产物纯度高,生产成本低,可工业化生产。公开号:CN103450219A  相似文献   

4.
晚清以来碑学大兴,大篆名家辈出,吴昌硕结体长方,左低右高,取斜势,陶博吾书自石鼓,自得天成,放逸随意,破石鼓文之匀雅,变而奇崛峭拔。大篆取向多样,吸引着学人为之研究,近人罗振玉、丁辅之、董作宾诸人均在此处取得了可贵的成就,张云龙先生所书的大篆有独到之处,《石鼓文》之外,兼擅《散氏盘》、《毛公鼎》、琅邪刻石等,于秦砖汉瓦自有天机处,别开新境。大篆是以形为上,云龙先生取钟鼎之浑圆,玉筋之婉通,或取诏版之方折,不拘泥于原形勾画。其大篆的线条自成一相,方圆错落有致,章法布白高妙,静中有动,动中有静,字距参差有致,行距疏宕有韵,别具生机。  相似文献   

5.
鞠洪振 《中国橡胶》2004,20(13):3-7
改革开放以来,我国橡胶工业的发展速度是前所未有的,其间有许多成功的经验,特别是入世后,在上世纪末全行业整体亏损的不利情况下,大家认识一致,认真对待,风雨同舟,趋利避害,经受住了考验,不仅行业经济全面复苏,而且取得新的发展。当前,全行业面对的是新一轮的竞争,而且更为激烈  相似文献   

6.
迟卫军 《化学与粘合》2007,29(6):451-453
以硫酸氢钠为催化剂,乙酸与乙醇为原料合成了乙酸乙酯,讨论了酸醇物质的量比、催化剂用量、反应时间、带水剂等因素对酯化率的影响,确定了最佳工艺条件为:以0.2mol乙醇为基准,酸醇物质的量比为1.5∶1,催化剂用量为1.5g,反应时间为2h,带水剂环己烷为10mL,乙酸乙酯的酯化率为85.2%.该催化剂具有催化效果好,使用量少,酯化率高,能够重复使用,环境污染小,腐蚀性小,价格低廉易得等特点,是一种很有发展前景的催化剂.  相似文献   

7.
《中国耐火材料》2015,(1):72-74
<正>Sinosteel Luoyang Institute of Refractories Research Co.,Ltd.(LIRR)is a science and technology enterprise affiliated to Sinosteel Corporation,China.LIRR,established in 1963,is the only large integrated research institute and the center of technology,science,information and services in refractories industry.Its business scope covers refractory products,testing equipment,processing tools,project design,consultation and turnkey,domestic and foreign trade,products quality inspection,information service,etc.  相似文献   

8.
《聚氨酯》2014,(7)
<正>一、市场行情简述本月行情:本月AA市场窄幅整理,月初,海力公布挂牌,受到上游原料纯苯强势走势影响,上调500元/吨,对外执行11,500元/吨,贸易商心态得到提振,纷纷上调报盘,刺激下游接货,但端午节后归市下游惯性观望,交投有限,中旬时期,随着下游进入传统行业淡季,需求明显萎缩,贸易商报盘坚挺,但实则成交重心暗降,随着明稳暗降操作,场内低价货源陆续增多,下游采购谨慎,临近月末,上游原料纯苯挂牌上调300元/吨,强势震荡影响市场操作积极性,海力又公布了6月结算价格,对外执行11,500元/吨,提振持货商心态,但实盘成交寥寥,下游需求跟进滞缓。上游原料:  相似文献   

9.
柳林小径深处,一扇木门掩映的白色建筑,即是王功新林天苗夫妇在宋庄的别墅。从大门进来,前方是白色的月亮门,像一道影壁墙,遮蔽外人的视线,经过一片水竹摇曳的甬道,才入院子。院内,三层小楼房顶上两层主体分别向两侧挑空,蜿蜒的池塘从花园延伸至室内,隔着一面大大的落地玻璃墙,恍惚间分不清哪里是室内,哪里是室外。更不可思议的是,池塘中间竟然是空的,下面就是那个巨大的工作室,鱼儿游过,涟漪荡漾开来,总担心这水会不会溢出……  相似文献   

10.
硫磺别名硫、胶体硫、硫黄块,外观为淡黄色脆性结晶或粉末,有特殊臭味.分子量为32.06,蒸汽压是0.13 kPa,闪点为207℃,熔点为119℃,沸点为444.6℃,比重、熔点及其在二硫化碳中的溶解度均因晶体不同而异,工业硫磺呈黄色或淡黄色,有块状、粉状、粒状或片状等.块状硫磺为淡黄色块状结晶体,粉末为淡黄色粉末,能溶于二硫化碳、四氯化碳和苯,不溶于水.  相似文献   

11.
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.  相似文献   

12.
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.  相似文献   

13.
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.  相似文献   

14.
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.  相似文献   

15.
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.  相似文献   

16.
石翛然 《广东化工》2014,(12):191-191
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%。  相似文献   

17.
王强 《中国陶瓷》2006,42(1):34-35
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。  相似文献   

18.
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...  相似文献   

19.
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。  相似文献   

20.
明胶分子量分布测定和表征的研究进展(二)   总被引:2,自引:1,他引:2  
<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  相似文献   

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