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1.
阐述了蛋白质等杂质对肌醇质量,得率以及原辅助材料消耗造成的影响,针对肌醇中蛋白质等杂质的特点,在不改变原生产流程,不增添设备前提下,采用净化剂FNO-10,在去除蛋白质方面取得了明显的效果,不但提高了肌醇的质量,而且提高了肌醇得率,减少了辅助材料的消耗,降低了生产成本。  相似文献   

2.
鉴于新型锌合金的硅含量,可高于常见锌合金的10倍,在用光度法测硅前,对单硅酸的聚合性问题,进行了理论分析,并作了试验验证。结果表明,新型锌合金在测定条件下,单硅酸不聚合,所配制的一系列测硅检量液可隔夜使用,这既保证了测硅的准确度,又简化了操作,提高了分析速度,节约了药品。  相似文献   

3.
复合稳定剂稳定过碳酸钠的研究   总被引:6,自引:0,他引:6  
研究了过碳酸钠的制备方法,筛选了合成的最佳工艺条件,对硅酸钠,三乙醇胺,乙二胺四乙酸钠等内稳定剂分别作了研究,选择了最佳内稳定配比,再结合外稳定剂复合稳定,产品稳定性好,有效氧含量高,工艺简单,具有较高的工业生产价值。  相似文献   

4.
氢化丁腈橡胶性能研究   总被引:8,自引:0,他引:8  
本文对氢化丁腈橡胶的基本特性进行了介绍,分别进行了补强剂,硫化剂,助交联剂的变量试验,讨论了补强剂,硫化剂,助交联剂对氢化丁腈橡胶性能的影响,同时还测试了常温条件下,热空气老化及浸油后的各项性能,还比较了不同温度条件下的压缩永久变形值,通过计算机将所测得的性能参数进行回归分析,从而进一步评价了氢化丁腈 橡胶的物理机械性能。  相似文献   

5.
汪凌云 《中国橡胶》1993,(20):11-12
1987年以来,跃进橡胶厂进行了卓有成效的技术改造,兴建了8000多m^2的成型大楼,淘汰了一些老设备,改建了2000m^2的制帮车间,新装了五条生产线,并对公用工程进行了填平补齐,从而为九十年代的经济发展奠定了物质基础,使企业长期保持兴旺发达。该厂的经验归纳起来有如下几点:  相似文献   

6.
符兴国 《广东化工》2003,30(1):40-43
本文分析了大储罐的结构,制造及设计,讨论了加工设计中面临的几个问题,介绍了实际的解决方法,详述了怎样解决尺寸确定,机构设计,加工制造,焊接的问题。  相似文献   

7.
本文归纳介绍了国外近年来发明的先进的几种典型筒式过滤机及其结构,工作原理,特点,应用范围等,并进行了分析,近年来,美国和日本等国家,发明了多种型式的,用于涂料,净化水及啤酒等工业上的筒式过滤机,这些过滤机,揭开了过滤行业的新纪元,促进了工业的发展。  相似文献   

8.
氨液浸出催化氧化制备硫酸铜晶体的方法探讨   总被引:1,自引:1,他引:1  
探讨了氨液浸出催化氧化制备硫酸铜的方法,并从热力学,动力学等角度进行了分析,对其反应可能性进行了论证,从多方面对反应机理进行了探讨。同时,将氨液浸出法与高温焙烧法作了对比,对其工业生产可能性作了分析,在多次实验的基础上,得出了较为合理的工艺条件。  相似文献   

9.
魏刚  陈建寿 《中国氯碱》2003,(10):16-18,24
通过改进工艺流程,科学确定加热面积的配比,合理选择采盐泵等技术改进措施,提高了生产强度,满足了高气压的生产条件,延长了洗效周期,减少了设备的腐蚀,提高了成品碱的质量,满足了生产联二脲的要求并降低了汽耗和电耗,年可节约ll0万元。  相似文献   

10.
利用橡胶和辉绿岩胶泥对混酸槽进行了复合衬里,该方法防腐败效果明显,降低了原材料的消耗,杜绝了跑,冒,滴,漏现象,这种方法简单易行,耗资少,使混酸槽的使用寿命延长,提高了经济效益。  相似文献   

11.
何丹辉 《中国塑料》2016,30(9):93-96
基于模外装饰工艺原理,对模外装饰自动换膜机构进行了详细设计,其中包含抚平轮和夹紧轮部分、机构固定部分、机架部分和裁刀部分。抚平轮和夹紧轮部分由抚平轮、夹紧轮、轴承、轴承套和摇杆等组成;机构固定部分由电机、压块、压块杆、轴承盖和摇杆等组成,机架部分由滚动导轨副、底板、滚珠丝杆副、步进电机、滚筒支架等组成;裁刀部分由侧板、导向杆、滑块和驱动电机组成。该套模外装饰自动换膜机构能够满足设计要求和实际需要。  相似文献   

12.
Carotenoids can be effective singlet oxygen quenchers and inhibit free-radical induced lipid peroxidation. A remarkable property of β-carotene ( 1a ) is the change from an antioxidant to a prooxidant depending on oxygen pressure and concentration. In the present study a considerable number of carotenoids ( 1a , 2c , 2d , 2e , 3a , 4a , 5a , 6a , 7a , 8a , 8h , 8i , 8j , 9f , 10a , 11a , 12g ) was investigated using two independent approaches: 1. Comparison of their effects on inhibition of the free-radical oxidation of methyl linoleate, and 2. The direct study of the effect of oxygen partial pressure upon their rates of oxidation. It is shown that some carotenoids ( 7a , 8a ) are even more effective than the well-known compounds β-carotene ( 1a ) and astaxanthin ( 5a ) and are powerful antioxidants without any prooxidative property. Different carotenoids display different behaviour depending on chain length and end groups. The influence of these functional groups on the antioxidative reactivity is discussed.  相似文献   

13.
Using a chronically placed jugular catheter and a silver electrode, it was possible to monitor short-term changes in the plasma concentration of cortisol and catecholamine in the marsupial sugar glider (Petaurus breviceps) and to monitor both heart and respiration rates. Males judged to be low in the social hierarchy of a particular group were exposed to the whole-body odor of a dominant male from the same social group, a foreign dominant male, or a castrate male. While there was no evidence of a change in any of the physiological parameters when a male was exposed to either a castrate male or a female, a rapid increase occurred in heart rate and plasma concentrations of cortisol, glucose and catecholamine when the donor was a dominant male from the same or a different social group.  相似文献   

14.
国内外己内酰胺生产现状及市场分析   总被引:2,自引:0,他引:2  
世界上最大的5家己内酰胺生产商是德国BASF公司,生产能力为55.5万T/a;荷兰DSM公司,生产能力为42.0万t/a;美国Allied-Signal公司,生产能力为32.7万t/a;日本宇部兴产公司,生产能力为26.8万t/a;日本东丽公司,生产能力为17.0万t/a。这5家公司的已内酰胺生产能力合计为174万t/a,约占世界总产量的50%。中国目前有4套己内酰胺生产装置,岳阳巴陵鹰山石化厂,2000年生产能力为7万t/a;南京东方公司,生产能力为6万t/a;石家庄化纤公司,生产能力为5万t/a;浙江巨化公司锦纶厂,生产能力为0.45万t/a,全国合计年生产能力为18.45万t/a。国外己内酰胺的主要消费领域为纤维、工程塑料和食品包装膜;国内已内酰胺的主要消费领域为帘子布、民用丝、工程塑料,所占比例分别为70%、28%、2%。国内己内酰胺需求一直大于国内产量,但由于技术力量薄弱、资金有限及下游产品结构不合理等原因制约了己内酰胺的应用,目前国内的已内酰胺主要应用在中低档产品中,高档产品所需己内酰胺仍要依靠进口。  相似文献   

15.
Examination of the receptive field structure of the retina suggested looking at small graphic figures of special forms. The luminance distribution called the “Mexican hat function” was approximated by a black dot with a small white dot at its center, called a “tip,” and the inverse function was approximated by a white dot with a small black dot at its center, called a “pit.” Such figures were given the generic name “tippit.” On a dark‐blue ground, tips looked yellow, and on a bright‐yellow ground, pits looked blue. Similarly, a black line with a white center, on a blue ground, and a white line with a black center, on a yellow ground, elicited these effects. On yellow and blue grounds, simple, small colored dots looked more like the color of the ground than when seen as large spots on a neutral gray ground, an effect here called “microspreading.” This effect may be attributable to scattering and blurring, but these processes do not account for the tippit effects. The visual system exaggerates contrast between a large spot and ground, and diminishes contrast between a small dot and ground, but exhibits neither effect on a figure of some intermediate size. Chromatic pit lines exhibit effects obeying laws of additive mixture. It appears that perceptions of these effects are normally repressed. No causal link was sought or established between receptive field theory and the observed effects. © 2003 Wiley Periodicals, Inc. Col Res Appl, 28, 242–250, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/col.10159  相似文献   

16.
气固流化床固体浓度分布的冷模研究   总被引:1,自引:0,他引:1  
在内径0.284 m、高6.0 m的气固流化床冷模装置中进行了气固流化实验,采用PC6 D型颗粒浓度测试仪检测固体浓度. 分别采用枝条型(开孔率a=5‰和2.5‰)和环形(a=5‰)气体分布器,以直径154~180 mm、密度2550 kg/m3的砂子为颗粒,在静床高H0=0.6~1.5 m、表观气速u=0.3~0.6 m/s的情况下,考察了时均固体浓度1-e在空间的分布. 结果表明,增加u使密相区的1-e减小,分布器形状对1-e影响不大. 采用较低a的分布器时1-e的变化较大,且其值均较低. H0=0.6 m, 轴向位置H=0.4 m, u=0.3 m/s, 径向位置r=0~0.142 m时,1-e由0.410上升到0.494;H0=0.6 m, H=0.4~0.95 m, u=0.3 m/s, r=0时,1-e从0.410减小到0;H0=1.5 m, H=0.4~1.3 m, u=0.3 m/s, r=0时,1-e从0.397先下降到0.372,再上升到0.424,最后下降到0.328.  相似文献   

17.
《Ceramics International》2020,46(17):27126-27133
As is well known, a way to obtain a high color resolution and saturation of a liquid crystal display and thereby obtain a higher visual accuracy and comfort in the coming 5G era remains an urgent challenge. In the present study, a new type of phosphor composite material doped with Ln3+ ions provides a promising alternative to the color filters used in White light-emitting diodes (WLEDs), achieving a better performance regarding the realization of a wider color gamut. The advantages of this composite material are illustrated through an abundant phase and morphology analysis along with a discussion regarding the X-ray photoelectron spectroscopy of the valence bond of Ce ions, which maintain the luminescence properties of the phosphor while providing a stable and solid amorphous environment. An improved spectral performance was obtained through color filtering at 580 nm along with the regulating effects of red, green, and blue emissions according to the doped Ln3+ ions. Notably, we fabricated a high-performance WLED based on a Ln3+-doped PiG with a correlated color temperature of 5037 K, color rendering index of 72.8, and high color gamut of 91.97%, providing a new choice for the development of luminescence materials with a high color resolution and saturation.  相似文献   

18.
目的分析1例新生儿血小板减少性紫癜(NAIT)血清中免疫抗体的特异性。方法采用固相凝集法检测患儿及其母亲血清中是否存在抗父亲/抗丈夫血小板抗体,用PAK12试剂盒鉴定血清中的抗体是抗-HLA还是抗-HPA,用ELISA法(PRA)鉴定HLA抗体的特异性,用SSOP法进行父亲、母亲和患儿HLA-Ⅰ类基因分型,用PCR-SSP法进行父亲、母亲和患儿HPA抗原1-5系统基因分型。结果该例NAIT患儿血清中存在来自母体的HLA-Ⅰ类抗体和HPA抗体;HLA-Ⅰ类抗体为抗-Bw6;父亲和患儿的HLA-B位点的宽特异性均为Bw4,Bw6,母亲为Bw4;患儿HPA抗原1-5系统基因型与父亲相同,有3a,母亲没有3a。结论在对NAIT患儿进行实验室诊断时,除注意HPA抗体的作用外,也应重视HLA-Ⅰ类抗体的作用。  相似文献   

19.
Chlorophyll pigments present in canola seed, meal and crude and degummed oils were analyzed by high-performance liquid chromatography (HPLC) with a fluorescence detector. Chlorophylls a and b, low levels of pheophytin a, and occasionally traces of pheophorbide and its methyl ester were present in canola seed. Meals and oils contained magnesium-deficient chlorophyll pigments such as pheophorbide a, methylpheophorbide a, pheophytins a and b, and pyropheophytins a and b but not chlorophyll a or b. The amounts of chlorophyll pigments were oil > seed >> meal. Both crude and degummed oils contained pheophytin a and pyropheophytin a as main components, but the ratio of pyropheophytin a to pheophytin a was markedly higher in degummed oils. No pheophorbides were detected in degummed oils. These results suggest that oil processing steps such as extraction and degumming affect the composition of chlorophyll pigments. Publication No. 678 Canadian Grain Commission.  相似文献   

20.
A stress distribution model for a liquid-solid circulating moving bed reactor that consists of a bottom reaction chamber, a top regeneration chamber, a coupling standpipe, a particle transportation system, and a bottom standpipe is established based on the equations of continuity and momentum balance. Simulations show that the stress concentration regions are at the bottom of the regeneration chamber and the coupling standpipe. To reduce the maximal stress and increase the operation flexibility in a reactor for the 2000-ton-per-year production of linear alkylbenzene, the regeneration chamber should have a low height-to-radius ratio (about 9), a suitable half-conical angle between 28° and 35°, and standpipe radius of about 0.05 m.  相似文献   

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