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1.
某7 500t/d水泥熟料生产线采用回转窑系统一键升温方案,应用新型智能控制平台软件,内置标准升温曲线程序,通过人工设置参数,改造现场装置及执行机构,按照烟室温度节点,控制中控设备开关量与执行器模拟量,实现了水泥回转窑的一键升温,达到了“慢升温、不回头、均匀烘窑”的升温要求,大大降低了劳动强度,有效减少了因升温速率不当导致的耐火材料损坏,实现了升温过程中启停设备及参数调整的标准化。  相似文献   

2.
采用有限元法数值模拟了3234/T300B热固性树脂基复合材料修补片的热补仪加热固化过程,分析了工程应用范围内不同升温速率下的复合材料修补片固化历程中的温度、热应力分布和变化特征,并研究了升温速率对补片在不同时间点的残余热应力值的影响规律。研究结果表明:升温阶段热应力主要集中在补片表面中心区域及其与母板接触的区域,降温阶段复合材料修补片内部热应力高于表面热应力;升温速率越快,固化越迅速,在升温阶段修补片内部热应力及峰值热应力越大;在保温和降温阶段,修补片内热应力分布和大小不受升温速率的影响;对于较低升温速率,热应力最大值出现在升温结束时刻;对于较高的升温速率,热应力最大值出现在接近升温末期的时刻。研究结果为合理选择升温速率从而减小升温阶段的内部热应力并控制补片分层等缺陷提供了参数依据。  相似文献   

3.
刘海成 《河南化工》2006,23(4):33-34,46
在合成氨生产中,分别采用分层升温还原法、整体升温还原法对Φ1 000和Φ 800氨合成塔同时进行升温还原,详述了其升温还原控制过程.  相似文献   

4.
针对气化炉预热烧嘴在升温初期火焰经常熄灭,很难保证按照耐火砖升温曲线进行升温和按照计划进行气化炉热备的问题,通过一系列措施解决了升温期间常见问题,在各项工艺条件正常的条件下,气化炉低温区极少出现灭火,保证了低温区升温正常进行的同时解决了升温期间积炭的问题。  相似文献   

5.
于增 《玻璃纤维》1994,(5):6-11
用“自电源升温法”代替传统的“他电源升温法”,可以缩短升温时间,简化升温操作,并节约电耗和硅碳棒损耗.“自电源升温法在陕西玻纤总厂已应用三年,升温四百多次,产生了很好的经济效益.  相似文献   

6.
尿素系统开车时首先要给合成塔升温,升温速度要均匀、缓慢。如果升温速度快会影响塔的使用寿命和生产安全。阐述了升温速度的控制及必要性,同时对一些不科学的习惯做法进行了简要分析。  相似文献   

7.
GHL01炸药烤燃实验的尺寸效应与数值计算   总被引:1,自引:0,他引:1  
在不同升温速率下,对不同尺寸的GHL01炸药装药进行了烤燃实验,建立了烤燃实验的计算模型。分析了装药尺寸对炸药烤燃临界环境温度和响应程度的影响,根据实验结果标定了反应模型的动力学参数。结果表明,GHL01炸药的烤燃实验存在一个临界升温速率,当升温速率大于临界升温速率时,随着装药直径的增加,炸药发生点火的临界环境温度增大,当升温速率小于临界升温速率时,随着装药直径的增加,临界环境温度先减小后增大,存在极小值(即最小临界环境温度),且随着升温速率的减小,最小临界环境温度降低。GHL01炸药的临界升温速率为0.2~0.4K/min。按照GHL01炸药点火的原因不同,提出了以临界升温速率作为慢速烤燃和快速烤燃的分界点。  相似文献   

8.
黄友良 《聚氯乙烯》2008,36(3):18-20
介绍了PVC生产过程中聚合釜升温的控制及其产生的影响,针对控制过程进行了理论计算,确定了需要升温的最高温度,提出了缩短升温时间的有效方法。  相似文献   

9.
介绍了在冶炼炉窑非连续性生产期间,为保证制酸系统转化工序正常运行和SO_2转化率,利用转化器四段升温阀门对将该部分低温烟气进行升温;合理控制投运电炉的数量,待出口烟气温度达到500℃左右时,再切换至转化器一段升温阀升温。该升温方法提高了电炉的利用率,避免了热能的浪费;节约了升温时间,降低了系统电耗。  相似文献   

10.
介绍了中海石油化学股份有限公司富岛二期合成氨装置氨合成塔热态升温情况,从氨合成塔概述、合成塔热态升温定义及热态升温过程等做详细的说明,分析讨论热态升温过程。  相似文献   

11.
The effectiveness of large single applications of North Carolina reactive rock phosphate, Queensland non-reactive rock phosphate, and Calciphos, were compared to the effectiveness of superphosphate in field experiments in south-western Australia for up to 11 years after application. As measured using plant yield, superphosphate was the most effective fertilizer in the year of application, and relative to freshly-applied superphosphate, the effectiveness of the superphosphate residues declined to be about 15 to 65% as effective in the year after application, and 5 to 20% as effective 9 to 10 years after application. Relative to freshly-applied superphosphate, all the rock phosphates were 10 to 30% as effective in the year of application, and the residues remained 2 to 20% as effective in the 10 years after application. The bicarbonate soil test reagent predicted a more gradual decrease in effectiveness of superphosphate of up to 70% 10 years after application. For rock phosphate, the reagent predicted effectiveness to be always lower than for superphosphate, being initially 2 to 11% as effective in the year after application, and from 10% to equally as effective 10 years later. Therefore rock phosphates are unlikely to be economic alternatives to superphosphate in the short or long term on most lateritic soils in south-western Australia.  相似文献   

12.
安克锰锌是烯酰吗啉两个异构体和代森锰锌组成的多元混合制剂。试样经粉碎、溶剂浸泡提取、混合柱净化,用气相色谱测定烯酰吗啉和代森锰锌母体(CS2),液相色谱测定代谢物乙撑硫脲(ETU)。仪器最低检出量:烯酰吗啉为1.436×10-12g,代森锰锌母体1.326×10-10g,ETU2.5×10-10g,最低检出浓度依次为0.02、0.025、0.02mg/kg,方法回收率依次为86.4%~90.8%、89.2%~95.9%、89.10%~95.13%;标准偏差为0.53~4.34;变异系数为0.58%~4.62%。安克锰锌在果皮中的消解方程广西和广东分别为C=1.2719e-0.1975T和C=1.045e-0.1972T,半衰期(T/2)均为3.5d;土壤中分别为C=0.8734e-0.1187T和C=0.6171e-0.1146T,半衰期(T/2)=6d;最高剂量250倍、最多施3次,最短距收期7d,在果肉中均未检出,果皮和土壤中的残留仅分别为0.1385~0.1745mg/kg和0.3105~0.3415mg/kg,均低于欧共体规定代森锰锌MRL值0.5mg/kg。  相似文献   

13.
Flehmen is a stereotyped response of ungulates and other mammals to urine. In black-tailed deer, Flehmen occurs typically in males (rarely in females), and its frequency shows an annual cycle. Flehmen in response to female urine was most frequent in November, and to male urine in January. The response minimum to both types of urine occurred in May. Fifty-five to 100% of initial responses to female urine resulted in Flehmen. The deer responded more often to female urine, and the difference between the responses to female and male urine increased from May to November. A male's own urine released Flehmen more often than did urine of other males. The response intensity varied with the spatial orientation of the male to the urinating female, and responses were usually limited to distances of 15 m or less.  相似文献   

14.
目的观察依达拉奉联合法舒地尔治疗缺血性脑卒中的临床疗效。方法对治疗组88例患者,对照组40例患者均给予脑梗死常规治疗,治疗组在此基础上加用依达拉奉联合盐酸法舒地尔,观察记录2组患者治疗前后症状、体征,神经功能缺损程度评分等各项指标。结果本研究中,2组患者接受治疗后均有明显疗效,但治疗组在神经功能缺损程度评分、有效患者例数和总有效率上均明显优于对照组(P<0.05)。结论依达拉奉联合法舒地尔治疗缺血性脑卒中可清除自由基,使脑梗死区域缺血半暗带的神经细胞功能得以恢复,减轻神经功能的损伤,有效的治疗缺血性脑卒中,效果明显,且无明显不良反应,适合在脑梗死临床治疗上推广。  相似文献   

15.
绿色环保意识的趋向   总被引:1,自引:0,他引:1  
随着消费者环保意识的提高,人们除了认清绿色环保能对社会和全世界起到巨大的促进作用,还认为绿色环保能够直接、积极地反映其社会地位,在某种程度上反映出消费者自己的绿色环保意识。介绍了消费者对"绿色化"的认识,对"绿色产品"的期望以及生产厂家对"绿色原料"的认证和对"可持续发展"所做的贡献。  相似文献   

16.
Responses by the insectivorous, actively foraging scincid lizard, Scincella lateralis, to chemical cues from a plant food favored by herbivorous lizards, its ability to discriminate prey chemicals from control substances, and its relative response to internal and surface prey chemicals were studied experimentally. We presented chemical cues to the lizards on cotton swabs and recorded their tongue-flicks and biting attacks on the swabs. The lizards exhibited significantly greater tongue-flick rates and biting frequencies to prey surface cues than to plant surface chemicals from romaine lettuce, diluted cologne (pungency control), and deionized water. Responses to the plant stimuli did not differ from those to the two control stimuli, in contrast with strong responses to the same plant cues by herbivores. This finding provides the first information suggesting that chemosensory response may be adapted to diet, with responsiveness to plant stimuli evolving de novo in herbivores. Biting and tongue-flicking responses were significantly greater to cricket chemicals than to all other stimuli, among which there were no differences. Thus, the lizards are capable of prey chemical discrimination, which may be ubiquitous among actively foraging lizards. The lizards exhibited more frequent biting and higher tongue-flick rates to internal than surface prey chemicals. Although different methods of stimulus preparation are appropriate for different purposes, we conclude that prey surface chemicals available to foraging lizards are most desirable for studies bearing on location and identification of prey.  相似文献   

17.
Hard clams, Mercenaria mercenaria, are sessile, filter-feeding organisms that are heavily preyed upon by blue crabs, which find their clam prey using chemical cues. Clams may evade blue crabs by reducing their pumping (feeding) behavior when a threat is perceived. The purpose of this study was to determine the type of signals that clams use to detect consumers. Clams decreased their pumping time in response to blue crabs and blue crab effluent, but not to crab shells, indicating that chemical signals and not mechanical cues mediated the response of clams to distant predators. Because predator diet can influence prey evaluation of predatory threats, we compared clam responses to blue crabs fed a steady diet of fish, clams, or that were starved prior to the experiment. In addition, we used injured clams as a stimulus because many organisms detect predators by sensing the odor of injured con- or heterospecifics. Clams reduced feeding in response to injured conspecifics and to blue crabs that had recently fed. Clams reacted similarly to fed crabs, regardless of their diet, but did not respond to starved blue crabs. Because blue crabs are generalist predators and the threat posed by these consumers is unrelated to the crab's diet, we should expect clam reactions to blue crabs to be independent of the crab's diet. The failure of clams to react to starved blue crabs likely increases their vulnerability to these consumers, but clam responses to injured conspecifics may constitute a strategy that allows animals to detect an imminent threat when signals emanating from blue crabs are not detectable.  相似文献   

18.
Previous research has shown multihue scales to be well‐suited to code categorical features and shown lightness scales to be well‐suited to code ordinal quantities. We introduce an algorithm, Motley, that produces color scales varying in both hue and lightness, intended to be effective for both categorical and ordinal coding, allowing users to determine both absolute and relative quantities efficiently and accurately. The algorithm first determines the lightnesses of scale colors to maximize perceived lightness differences and establish the lightness ordering, generating separate search spaces for each scale position. It then selects hues by heuristic search to maximize the discriminability of the scale. It produces scales that are ordered with respect to lightness but unordered with respect to hue and thus more discriminable than typical multihue lightness scales. In an experimental evaluation on human subjects, Motley's scales enabled accurate judgments of relative quantity, with response times superior to unordered multihue scales and comparable to ordered lightness scales, and enabled accuracy and speed of judgments of absolute quantity superior to lightness scales and comparable to multihue scales. Published 2009 Wiley Periodicals, Inc., Col Res Appl, 2010.  相似文献   

19.
In this study, crisp and fuzzy multiple-goal optimization approaches are respectively introduced to design an optimal biocompatible solvent to a two-stage extractive fermentation with cell recycling for ethanol production. When designing a biocompatible solvent for the extractive fermentation process, many issues, such as extractive efficiency, conversion, amount of solvent utilized and so on, have to be considered. An interactive multiple-goal design procedure is introduced to determine a trade-off result in order to satisfy such contradicted goals. Both approaches could be iterated to solve the interactive multiple-goal design problem in order to yield a trade-off result. However, the crisp optimization design is a tedious task that requires the designer to provide various pairs of the upper bounds for the design problem to obtain the corresponding solution. The fuzzy optimization approach is able to be trade-off several goals simultaneously and to yield the overall satisfactory grade for the product/process design problem.  相似文献   

20.
煤或天然气经甲醇制低碳烯烃工艺研究新进展   总被引:15,自引:0,他引:15  
由煤或天然气经甲醇制低碳烯烃工艺是解决石油资源紧张、低碳烯烃需求量越来越大等问题的有效路线。介绍了几种有代表性的经甲醇制低碳烯烃工艺,包括美国UOP/Hydro甲醇制烯烃工艺,中国科学院大连化学物理研究所的合成气经由二甲醚制低碳烯烃(SDTO)工艺,德国Lurgi公司的甲醇制丙烯工艺,以及甲醇制烯烃与AtoFina/UOP烯烃裂解的集成工艺;分析了各工艺目前达到的技术指标及最近的技术改进,关注了各工艺近几年的工业化进程。除了SDTO工艺外,其他几种工艺有望在未来几年内实现工业化。国内甲醇制低碳烯烃工艺的开发应借助于流化催化裂化成熟的工程设计经验,同时加大甲醇制烯烃工艺流化床催化剂的开发力度。  相似文献   

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