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991.
用灰色关联分析影响转杯纺纱品质指标的因素 总被引:5,自引:0,他引:5
采用棉纤维的 H V I指标,应用灰色关联分析法指出在棉纤维的各项 H V I指标中,纤维强力是与转杯纱的品质指标密切相关的,用高强力、低马克隆值的原棉可以获得高品质指标的转杯纱。 相似文献
992.
The conductivity of polypyrrole films has been enhanced by electrochemical post-deposition doping with various anions. The change of conductivity was found to depend on the type and concentration of the anion. Results for the polypyrrole films doped with anions of H_2SO_4,,(C_2H_5)_4, N(O_3 SC_6H_4CH_3), KI,CH_3 C_6H_4 SO_3 H·H_2O(p-Toluene Sulfonic acid Monohydydrate), AlCl_3, KBrO_3 and HNO_3 showed that in the case of H_2 SO_4, (C_2H_5)_4 N(O_3SC_6 H_4 CH_3)and CH_3C_6H_4SO_3H·H_2O the conductivity can be enhanced by up to a factor of two, from a value of 67 sem~(-1) up to 165, 102 and 95 s cm~(-1), respectively. Doping with I~- had a negligible effect on the conductivity which was about 71 s cm~(-1), while in the case of AlCl_3, KBrO_3 and HNO_3 the conductivity of the polypyrrole decreased significantly for certain anion concentrations. 相似文献
993.
994.
995.
HANS J R 《中国科学:技术科学》2010,(4)
The anisotropic plastic deformation behavior of as-extruded ZK60 magnesium alloy at room temperature(RT)was investigated by compressive and tensile testing in different directions,i.e.the loading axis oriented at 0°,45°and 90°to the extrusion direction.The relationship between texture and plastic deformation behavior were examined.The results show that the extruded ZK60 alloy exhibits a strong ring fiber texture.The mechanical properties are strongly orientation dependent.In tension testing,the 0°specimen exhibited higher yield strength and lower elongation.In compression testing,however,ZK60 alloy exhibited almost the same yield strength in three directions.The anisotropic plastic deformation behavior is due to strong fiber texture and the lower symmetry of the hexagonal close packed(hcp)structure of ZK60 alloy. The correlation between texture and mechanical behaviour offers the possibility to improve the mechanical properties of magnesium alloy by optimization of the material production process. 相似文献
996.
Synthesis and Characterization of Quaternary Complexes Ln(CH_2ClCOO)_2 (NO_3) (phen) 总被引:4,自引:0,他引:4
Many binary lanthanide complexes have been studied. However, few mixed anion complexes with bidentate heterocyclic amines were synthesized. We synthesized mixed anion complexes Ln ( CH2 ClCOO )2 (NO3 ) ( phen) which was determined by elemental analyses . The IR spectra analyses indicate that NO3- , CH2 ClCOO- and phen are coordinated with Ln . The molar conductances of the complexes at 10-3 mol · L-1 were founded to be between 32.4 and 35.8 S·cm2· mol-1 , suggesting the nonelectrolytes in N-Dimethylformamide. And we determined the fluorescent spectra Eu(CH2ClCOO)2(NO3) ( phen ) and ESR spectra of Gd ( CH2 ClCOO )2 ( NO3) ( phen) . 相似文献
997.
Intheserialreports[1,2]ofskincoldsensitivedifference ofhumanbodysectionsunderclothing,thepatternofskin temperature smaximumchangesanddynamicchanging processonhumanbodysectionsstimulatedbythesame intensivecoldunderclothingisreported.Atthesame time,bodysectionsaffectedbythesamecoldstimulus resultsinwearers psychologicalperceptiondifference,whichcouldberesearchedintheaspectofsenseand consciousness.Traditionally,senseandconsciousnessbelongto psychologycategory.Tostudysenseandconsciousnessrelated t… 相似文献
998.
研究了用红外光谱法分析 AN/VAc/MAS的共聚物组成及序列分布,比较了 AN/VAc与 AN/MA共聚物质序列分布。研究表明:共聚物中VAC含量低于10%时,大分子主键上VAc-VAc键接的可能性很小,说明了 VAc单元比较均匀地分布在大分子主键上,这对于纤维性能的均一稳定非常有利。第二单体VAc代替MA完全可行。 相似文献
999.
Automatic Measurement for Fabric Surface Shapes with Two-Dimen-sional Fourier Transform Profilometry
Two- dimensional Fourier transform profilometry (2 -D FTP) for data acquisition of fabric surface shapes isproposed. Phase unwrapping technique based on digitalweighted filter and reliability mask are employed. Ex-perimentai results of shape measurement for several fab-ric appearances are given. From the measured results, itis shown that this method can make up for not only thedisadvantage of the gray level image analysis which isonly suitable for simple structure and solid - pattern fab-ric, but also the low speed and high cost of laser dotscanning technique. 相似文献
1000.
Adsorption isotherms for SF cellulase from Trichoderma pseudokoningii on cotton, flax and viscose yarns were investigated to provide information about cellulase-cellulose binding on different types of cellulosic fibres. The half-saturation constants and maximum adsorption constants suggest that SF cellulase has greater affinity for viscose than for cotton and greater affinity for cotton than for flax. It is suggested that this is related to the different crystallinities and microporous structures of these fibre types. The fraction of adsorbable protein in the total cellulase was found to be the same for each of the three cellulase substrates. 相似文献