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1.
粘胶在酸浴中成形为粘胶人造丝。硫酸锌是凝固浴的重要组成部分,硫酸锌使纤维具均匀的小晶区结构,而增加纤维强度,在粘胶中添加尿素可部分取代 ZnSO_4的作用。这不仅可降低成本,而且可降低生产废水中 Zn~(2+)浓度,对环境保护有重要意义。  相似文献   

2.
纤维素经过黄化制得的粘胶溶液在溶解与熟成时,其化学和物理化学过程仍在继续进行着,制得的粘胶溶液其可纺性可由熟成度确定,而粘胶的熟成度表示了粘胶的胶态稳定性。本文通过对溶解和熟成初期过程的研究,着重论述了粘胶的胶态稳定性与纤维素黄酸酯的酯化度、溶液中碱的浓度和CS2用量之间的关系。  相似文献   

3.
溶解机是粘胶制备中用来将黄化后的粘胶循环、溶解,并贮存粘胶的搅拌设备。搅拌装置是其重要的组成部分,在搅拌装置中,搅拌轴作为重要的部件其设计结构直接影响着粘胶搅拌溶解效果。本文以我公司溶解机为例简要介绍分析了溶解机搅拌轴的设计.  相似文献   

4.
花板是布袋除尘器的重要部件。本文以某电厂2×300MW机组布袋除尘器花板为研究对象,利用ANSYS有限元分析软件进行了优化分析。对3种结构方案进行了详细计算分析,优化后的加固肋重量下降了30%以上,为布袋除尘器花板设计和工程实践提供了可靠依据。  相似文献   

5.
袋式除尘器花板等效力学性质分析   总被引:1,自引:0,他引:1  
将均匀化方法与有限元法结合起来,采用单胞法分析周期性分布、含圆孔袋式除尘器花板的等效力学性质,通过对含密集型周期分布圆孔袋式除尘器花板的挠度和模态对比分析,证实了均匀化方法的有效性,进一步研究了花板圆孔半径和圆孔中心距对花板等效弹性常数的影响规律.结果表明:a.在圆孔半径相同情况下,随着圆孔中心距的增大,花板等效弹性模量逐渐增大,但等效泊松比逐渐减小;b.在圆孔中心距相同情况下,随着圆孔半径的增大,花板等效弹性模量逐渐减小,但等效泊松比逐渐增大.  相似文献   

6.
吴激扬 《科技资讯》2013,(8):107-108
花板、滤袋是电袋除尘器重要部件。花板是滤袋安装接口,因此花板的机加工精度和拼装焊接工艺对滤袋除尘效果影响很大,本文着重从花板的形状公差和位置公差、拼装焊接工艺等方面来分析对滤袋除尘的影响。  相似文献   

7.
本文主要探讨在单元液流流出喷丝头,丝条成形过程断头的诸多原因;单元纤维的凝固速度和成形过程的稳定性与酸浴浓度的关系。研究丝条断头原因和如何防止此现象发生一直是粘纤厂比较紧迫的课题。生产中丝条断头会带来诸多不便,造成纺丝溶液损失,增加更换喷丝头次数,恶化凝固浴,降低设备生产能力,在此有必要对纺丝断头原因加以探讨。  相似文献   

8.
油浴/干式组合空滤器在格尔发上的应用与分析   总被引:1,自引:0,他引:1  
文章分析了空气滤清器在格尔发重卡上的应用现状,介绍了油浴/干式组合空气滤清器的内部结构、工作原理和组合形式,根据重卡某车型发动机的理论要求,通过经验公式和软件工具对油浴/干式组合空气滤清器所需额定空气流量进行设计计算,并通过台架试验进行验证,结果表明该过滤系统应用于我公司重卡此车型上是完全合理的,为其他变型产品的开发提供了基础.  相似文献   

9.
选择气隙高度、凝固浴温度、拉伸速度3种工艺参数作为研究对象,并设计3因素4水平的正交实验来分析制膜条件对纤维素膜力学性能的影响.通过结果分析得出:影响纤维素膜力学性能的主要因素为凝固浴温度,其次为拉伸速度以及气隙高度.最优的制膜条件为:气隙高度32,mm,凝固浴温度20,℃、拉伸速度500,mm/min.最优组合所得纤维素膜拉伸强度为13.68,MPa、断裂伸长率为79.37%.对最优组合、正交表中综合评分最高值与最低值3种试样进行结晶度与断面结构的对比,结晶度分别为63.27%、72.7%、54.74%,在膜断面结构方面,最优组合膜较另外两者呈现出更均匀且致密的断面结构.  相似文献   

10.
大麻碱氧一浴一步法短流程脱胶漂白工艺参数的优化   总被引:5,自引:0,他引:5  
大麻碱氧一浴脱胶漂白工艺流程短,去除木质素效果好。通过三因子二次通用旋转组合回归优化设计方法进行了大麻碱氧-浴脱胶漂白工艺探索,讨论了各工艺因素对精干麻残胶率、残余木质素量、精干麻强力和白度的影响,经过优化实验、计算与分析,得到了最优工艺参数。  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.  相似文献   

13.
王慧 《科技信息》2008,(10):240-240
Wuthering Heights, Emily Bronte's only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.  相似文献   

14.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

15.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

16.
Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.  相似文献   

17.
以AC-13级配为基础,将橡胶颗粒代替部分集料掺入混合料中,以低温弯曲试验为评价方法对不同橡胶颗粒掺量下沥青混合料的低温抗裂性进行研究,并引入应变能密度值对混合料的低温抗裂性进行综合评价.试验结果表明:橡胶颗粒沥青混合料试件的破坏微应变均超过2 300,满足冬寒区的技术指标;无论是否掺加橡胶颗粒,随着温度的下降,沥青混合料破坏时的最大弯拉强度增大,弯拉应变降低,劲度模量增大;弯曲应变能密度在胶粒掺量为1%左右时具有较大的弯曲应变能密度值,此时橡胶颗粒沥青混合料具有较好的低温抗裂性.  相似文献   

18.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

19.
Quality traits in wheat (Triticum aestirum L.) were studied by quantitative trait locus (QTL) analysis in a recombinant inbred line (RIL) population, a set of 131 lines derived from Chuan 35050 × Shannong 483 cross (ChSh). Grains from RILs were assayed for 21 quality traits related to protein and starch. A total of 35 putative QTLs for 19 traits with a single QTL explaining 7.99-40.52% of phenotypic variations were detected on 10 chromosomes, 1D, 2A, 2D, 3B, 3D, 5A, 6A, 6B, 6D, and 7B. The additive effects of 30 QTLs were positive, contributed by Chuan 35050, the remaining 5 QTLs were negative with the additive effect contributed by Shannong 483. For protein traits, 15 QTLs were obtained and most of them were located on chromosomes 1 D, 3B and 6D, while 20 QTLs for starch traits were detected and most of them were located on chromosomes 3D, 6B and 7B. Only 7 QTLs for protein and starch traits were co-located in three regions on chromosomes 1D, 2A and 2D. These protein and starch trait QTLs showed a distinct distribution pattern in certain regions and chromosomes. Twenty-two QTLs were clustered in 6 regions of 5 chromosomes. Two QTL clusters for protein traits were located on chromosomes 1D and 3B, respectively, three clusters for starch traits on chromosomes 3D, 6B and 7B, and one cluster including protein and starch traits on chromosome 1D.  相似文献   

20.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

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