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1.
本文对PEW(PEW)在溶剂中的溶解度和溶解时间进行了测定,研究了PEW分子量、溶解温度对溶解度和溶解时间的影响。采用溶解方法对灰色PEW进行了脱色试验,通过白度、原子吸收分光光度分析证明,PEW中的有色杂质被有效去除,并初步认定有色杂质可能来自于聚合体系中的引发剂。  相似文献   

2.
通过高温索氏提取法采用混合溶剂(V正庚烷∶V二甲苯=1∶4)对土壤中的可降解聚乙烯(PE)残余物(PEW,Mw=5 000)进行分离提取,分别考察了提取时间和土壤类型对PEW提取率及结构和热性质的影响,同时做根窖实验并进行相对分子质量的测定。结果表明,对PEW的提取率随提取时间的增加而增大,2.5h后达最大(92.5%);提取时间对PEW的分子结构无明显影响,但对PEW的结晶有一定影响,使得熔融温度和结晶温度分别升高1~3℃;提取时间对PEW的平均相对分子质量无明显影响,但会导致相对分子质量分布变窄;土壤类型对PEW的提取率基本没有影响;根窖实验结果表明该提取方法可以用于实际土壤中PEW残余物的降解测试评价,长期跟踪下去还可以评估PE完全降解所需时间。  相似文献   

3.
研究了聚乙烯蜡(PEW)与马来酸酐(MAH)熔融接枝反应,在PEW分子链上引入了极性基团。采用红外光谱(IR)和核磁共振谱(NMR)表征了接枝物的结构,采用滴定法测得接枝物的酸值在25~60mgKOH/g之间。研究了接枝单体MAH、引发剂过氧化二异丙苯(DCP)和抗氧剂1010用量对接枝物酸值的影响。结果表明,在一定条件下接枝产物的综合性能较好。  相似文献   

4.
催化裂化汽油中乙腈萃取脱硫的研究   总被引:3,自引:0,他引:3  
以乙腈为萃取剂,在正辛烷中加入少量噻吩构成汽油模拟体系,考察了稀释剂含量、剂油比、温度对脱硫率和分配系数的影响.实验结果表明:采用溶剂乙腈脱除催化裂化(FCC)汽油中的硫化物是可行的,乙腈是一种较好的萃取剂.建立了在模拟体系中噻吩的萃取动力学方程:r表现=56.1×e(-16.1/T)CA以及不同温度和不同稀释剂含量下的萃取平衡线.模拟体系萃取脱硫适宜的条件为稀释剂体积含量1%~3%,剂油质量比0.8~1.2,萃取温度为常温.在该条件下对催化裂化汽油进行萃取精制,精制汽油硫含量达到欧Ⅳ标准.  相似文献   

5.
糠醛精制润滑油及其人工神经网络的平衡模拟和预测   总被引:1,自引:1,他引:0  
实验研究糠醛精制润滑油过程中温度、醛油比对精制结果的影响.把油品的四个质量指标(折光率、酸值、碱性氮、苯胺点)虚拟成四个组分,对糠醛精制过程建立平衡衡算关系.用人工神经网络算法建立多变量体系的平衡计算.应用该平衡计算结合原油的质量指标预测一定温度和醛油比下精制油的质量指标和收率,得到满意的结果.  相似文献   

6.
利用体质测量和体成分分析仪检测356名50~70岁南阳市的汉族女性的体质指标和体成分指标,对肝脏进行B超检查.从人体组成学的角度探讨绝经前后女性非酒精性脂肪性肝病(NAFLD)与体成分变化之间的关系.结果显示:绝经前(PEW)、绝经5年(AM5)和绝经10年(AM10)的肥胖率分别为24.5%、31.4%和28.4%.肥胖女性的身体脂肪、内脏脂肪和脂肪比均高于同期健康女性人群(P0.01);PEW、AM5和AM10的肥胖群体NAFLD患病率分别为26.9%、51.4%和34.2%,高于健康群体患病率(P0.01),肥胖是绝经期女性NAFLD患病率的危险因素;与PEW相比,AM5和AM10的腰臀比(Waist to Hip Ratio,WHR)升高,NAFLD患病率与腰围(Waist,WC)和WHR的相关性最高,绝经女性NAFLD患病率高于未绝经女性,WC和WHR可以作为预测NAFLD患病率的可靠指标.  相似文献   

7.
为得到高纯度的凝胶多糖,采用分级膜(30 ku,100 ku)超滤同时耦合溶析结晶的方法——循环超滤-溶析结晶(CUSOC)法对凝胶多糖粗品进行了分级纯化,制备出了纯度分别达96.5%和93.3%的凝胶多糖产品,并对100 ku膜截留液所精制的多糖(CUD3)的组成进行了初步分析.结果表明,整个工艺过程的多糖截留率都在95%以上,多糖聚合物总收率约为93.10%.紫外光谱和纸层析鉴定表明,CUSOC方法能有效除去大部分小分子色素及核酸类杂质,凝胶多糖的水解物为单一葡萄糖.红外光谱分析表明,该多糖属β-D-糖苷键构型.  相似文献   

8.
为了对化工企业存在的风险进行分级管控,采用层次分析法构建了化工企业风险分级管控体系评价指标,该评价体系指标包括风险分析与分级、隐患排查与治理、管理水平,措施保障、应急管理、职业健康6个二级指标因素和28个三级指标因素,并运用MATLAB软件对各指标权重进行计算。采用模糊综合评价法确定了4个评价等级,根据隶属度原则得出风险分级管控等级。以某化工企业为例,运用AHP-模糊综合评价法对该化工企业的风险进行分级评价,得出该化工企业风险分级管控总依得分  相似文献   

9.
对天然矿石蜡进行了脱树脂及氧化精制研究,探索国产矿石蜡能否通过精制后满足合成改性浅色蜡如O蜡、E蜡、OP蜡的使用要求。实验结果表明,该天然矿石蜡很难制成完全的乳白色蜡。研究了一种用浓H2SO4 K2Cr2O7对其进行氧化精制的优化方法,并讨论了该天然矿石蜡不能完全脱色的主要原因。  相似文献   

10.
转盘塔内糠醛精制润滑油过程研究   总被引:2,自引:0,他引:2  
针对糠醛、润滑油体系的特点,研究了转盘转速,溶剂比和精制温度对润滑油精制结果的影响,得出了优化的操作组合条件,通过对实验数据的关联拟合,得出了润滑油粘度指数和收率随操作因素变化的无因次关联式。  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.
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   

15.
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   

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.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

19.
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   

20.
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   

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