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821.
In this work,the effect of dioctadecyl dimethyl ammonium chloride(DDAC,a kind of alkyl ammonium salt) on polar β phase content and the diameter of electrospun PVDF nanofibers was investigated for the first time.Our experimental results show that the diameter of the electrospun PVDF nanofiber could be largely reduced and the content of polar β phase also become dominant immediately by just adding a little amount of DDAC.When the mass fraction of DDAC reached 4%,the content of polar β phase increased by about 39.1% compared with PVDF nanofibers without DDAC.Besides,the crystallinity of PVDF nanofibers also increased with the addition of DDAC.Based on the results,the possible mechanism of cooperative effect between electrospinning and DDAC on fiber diameter and formation of β phase in PVDF was discussed. 相似文献
822.
Song Li Xupeng Cao Yan Wang Zhen Zhu Haowei Zhang Song Xue Jing Tian 《Applied biochemistry and biotechnology》2017,183(3):923-930
With the fast development of microalgal biofuel researches, the proteomics studies of microalgae increased quickly. A filter-aided sample preparation (FASP) method is widely used proteomics sample preparation method since 2009. Here, a method of microalgae proteomics analysis based on modified filter-aided sample preparation (mFASP) was described to meet the characteristics of microalgae cells and eliminate the error caused by over-alkylation. Using Chlamydomonas reinhardtii as the model, the prepared sample was tested by standard LC-MS/MS and compared with the previous reports. The results showed mFASP is suitable for most of occasions of microalgae proteomics studies. 相似文献
823.
Can Cao Li Zhang Jian Gao Hong Xu Feng Xue Weiwei Huang Yan Li 《Applied biochemistry and biotechnology》2017,182(2):687-696
R,R-2,3-butanediol (R,R-2,3-BD) was produced by Paenibacillus polymyxa ZJ-9, which was capable of utilizing inulin without previous hydrolysis. The Jerusalem artichoke pomace (JAP) derived from the conversion of Jerusalem artichoke powder into inulin extract, which was usually used for biorefinery by submerged fermentation (SMF), was utilized in solid state fermentation (SSF) to produce R,R-2,3-BD. In this study, the fermentation parameters of SSF were optimized and determined in flasks. A novel bioreactor was designed and assembled for the laboratory scale-up of SSF, with a maximum yield of R,R-2,3-BD (67.90 g/kg (JAP)). This result is a 36.3% improvement compared with the flasks. Based on the same bath of Jerusalem artichoke powder, the total output of R,R-2,3-BD increased by 38.8% for the SSF of JAP combined with the SMF of inulin extraction. Overall, the utilization of JAP for R,R-2,3-BD production was beneficial to the comprehensive utilization of Jerusalem artichoke tuber. 相似文献
824.
REMARK ON STABILITY OF ISHIKAWA ITERATIVE PROCEDURES 总被引:2,自引:0,他引:2
1 IntroductionandPreliminariesSupposeEisarealBanachspaceandTisaselfmapofE .Supposex0 ∈Eandxn+1=f(T ,xn)definesaniterationprocedurewhichyieldsasequenceofpoints xn ∞n=0 inE .Foranexample ,thefunctioniterationxn+1=f(T ,xn) =Tx0 .SupposeF(T) =x∈E :Tx=x ≠ andthat xn convergess… 相似文献
825.
826.
利用磁性流体被磁场吸附的原理,探讨了氮化铁磁性流体密封装置的设计原理和动作过程,分析并通过试验验证了磁性流体密封承压能力,进而成功地研制了氮化铁磁性流体密封安全阀,基于磁性流体密封安全阀开启压力稳定性、可控性和密封性能测试结果,所研制的样机已正常运行10000h。 相似文献
827.
粘性减阻技术及其应用 总被引:11,自引:1,他引:11
本文综述了几种粘性减阻方法及其减阻的机理,联系了其在水相、油相中节约能源、材料,提高速度和效率等方面的应用 相似文献
828.
829.
Xin Ping Ouyang Pan Zhang Chun Mei Tan Yong Hong Deng Dong Jie Yang Xue Qing Qiu 《中国化学快报》2010,21(12):1479-1481
<正>Lignosulfonate with low polydispersity index of 1.178-1.210 was isolated by gel column chromatography of Sephacryl S-100 eluted with 0.2 mol/L of NaNO_3 aqueous solution,whereas nearly monodisperse ligosulfonate fraction with polydispersity of 1.0(57 can be obtained after chromatographic separation twice.This method provides an available approach to investigate the structure and characteristics of lignosulfonate. 相似文献
830.
<正>A novel polyamide containing xanthene structure and trifluoromethylphenoxy pendent was prepared from 9,9-bis[4-(4- aminophenoxy)phenyl]xanthene,a novel diamine with 2-(4-trifluoromethylphenoxy)terephthaloyl chloride,by the low temperature polycondensation.This new polyamide with the inherent viscosity of 0.95 dL/g was amorphous and readily soluble in polar solvents such as DMAc,m-cresol,etc.This polyamide showed the glass transition temperature(T_g) of 236℃,decomposition temperature (Td) at 5%weight loss of 455℃and char yield of 56%at 800℃in N_2.Transparent,flexible,and tough film of the polymer cast from DMAc solution exhibited tensile strength of 93 MPa,elongation at break of 14%,initial moduli of 2.2 GPa.The electric properties such as the dielectric constant of 3.03(1 MHz) and surface resistance(2.78×10~(14)Ω),and the moisture uptake of 1.36% were also described. 相似文献