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991.
A201D型精梳机是国内目前精梳主要机型,我公司1984年至1998年先后购进14套(56台)使用至今。使用中发现曲线斜管牙结合件———上圈条盘(A201C-5300A-8B)内弧形管连接处挂花较为普遍,严重影响条干CV值及纱线质量。观察发现,上圈条盘与弧形管固定连接处的夹层是由尼龙充塞平磨而成,经过多年的使用尼龙充塞夹炽老化、收缩,造成尼龙层与上盘铸铁件形成一定的间隙,使上圈条盘运动时形成一处或多处挂花,从而形成并条、粗纱纱疵,影响条干,并增加挡车工的劳动强度。为此,采取了两种简便处理方法:a)清理上圈条内弧形管与上圈条盘间尼龙夹层,清理… 相似文献
992.
993.
Tingfang Hu Jinpeng Chen Haiyan Wang Jun Min Wei 《Petroleum Science and Technology》2006,24(12):1477-1484
Etherification reaction of FCC light gasoline over Hβ zeolite was investigated to decrease the light olefins in motor gasoline while enhancing octane. Etherification activity of several molecular sieve catalysts for FCC light gasoline was studied in a fixed-bed reactor. The influence of pore-enlarging agent (PEG) with different molecular weight, binder (γ-Al2O3), and peptizing agent (HNO3) in the shaping process on etherification activity of Hβ zeolite was studied. The impregnating ways of precursor of oxides and the order of extruding and impregnating were also investigated. The results show that the activity of extruded Hβ zeolite before impregnating precursor of oxides is higher than the reverse order. The best shaping condition obtained was PEG-4000 10%, γ-Al2O3 20%, and HNO3 10%. At the optimal reaction condition, the conversion of tert-olefins reached the peak. 62.93%, the yield of TAME, is also high and the technology can be applied to industry as well. 相似文献
994.
航空放射性遥感系统采用航空γ能谱仪,在空中飞行探测地表放射性,能够快速进行大面积环境放射性调查。结合已经开始进行的首次大面积航空放射性遥感调查工作,简要介绍了航空放射性遥感系统构成、核探测γ能谱测量和数据处理技术。对系统转换因子刻度和剥离系数刻度方法进行了讨论,并对初步应用情况进行了总结。 相似文献
995.
Woo Yong Sung Seung Min Lee Wal Jun Kim Jong Girl Ok Ho Young Lee Yong Hyup Kim 《Diamond and Related Materials》2008,17(6):1003-1007
Complementary electroplating combined with electrophoresis enhanced the field emission characteristics of emitters by improving the adhesions between CNT emitters and substrate. The emitting current of the CNT emitters prepared by our combined method increased nine times higher than that of CNT emitters prepared by electrophoresis only, since electroplating improved the adhesion of CNT emitters. During the life-time measurement for 10 h, the emitting current of CNT emitters fabricated by electrophoresis only was drastically decreased to 13% of the initial current, while that prepared by the combination of electrophoresis and successive electroplating decreased to 64% of the initial current. We suggest that our method is a promising approach for the efficient fabrication of reliable CNT emitters. 相似文献
996.
Chun Lin Ma Qing Feng Wang Rufen Zhang Jikun Li 《Journal of Inorganic and Organometallic Polymers and Materials》2008,18(2):229-235
Six triorganotin(IV) complexes of the type {(R3Sn)2[C3S3(COO)2]}n (R = C6H5 1; n-Bu 2; PhCH2 4; p-F-PhCH2 5; o-F-PhCH2 6) and {(R3Sn)2[C3S3(COO)2]}n·[EtOH] (R = Me 3) have been synthesized by the reaction of bis(carboxymethyl)trithiocarbonate with triorganotin(IV) chloride
in the presence of sodium ethoxide. All complexes were characterized by elemental analysis IR, 1H, 13C and 119Sn NMR spectroscopy. Except for 4–6, all complexes were also characterized by X-ray crystallography. The X-ray date revealed
that complexes 1–3 show two-dimensional network polymeric structure in which the geometries of tin atoms are trigonal bipyramid
with the axial positions occupied by carboxylic oxygen atoms. 相似文献
997.
In electrophotographic printing, a periodic clustered-dot halftone pattern is preferred for a smooth and stable result. In addition, the screen frequency should be high enough to minimize the visibility of the halftone textures and to ensure good detail rendition. However, at these frequencies, the halftone cell may contain too few pixels to provide a sufficient number of distinct gray levels. This will result in contouring and posterization. The traditional solution is to grow the clusters asynchronously within a repeating block of clusters known as a supercell. The growth of each individual cluster is governed by a microscreen. The order in which the clusters grow within the supercell is determined by a macroscreen. Typically, the macroscreen is a recursive pattern due to Bayer. In highlights and shadows, this ordering results in visible artifacts. Replacing the Bayer screen by a stochastic macroscreen eliminates these artifacts, but results in new artifacts. In this paper, we propose a new composite screen architecture that employs multiple microscreens and multiple macroscreens in the highlights and shadows. These screens are jointly designed by using the direct binary search (DBS) algorithm. 相似文献
998.
To apply wavelet transformation to CAD surface model composed of multiple surface patches, an algorithm called wavelet signal separation to preserve geometric constraints during wavelet transformation is proposed. The algorithm divides the B-spline control points into those associated and those unassociated with the geometric constraints. Through preserving the signal information associated with the constraint control points, the geometric constraints can be automatically preserved after wavelet transformation. This paper also briefly investigates two types of the detail feature propagation technique in wavelet-based multiresolution CAD system. One is detail feature motion. The other is detail feature repetition. Finally, a comprehensive example is presented to illustrate the effects of the combination of those techniques. 相似文献
999.
1000.
Qi Gong Wei Lin 《Automatic Control, IEEE Transactions on》2003,48(6):1049-1054
This note shows how the adaptive control method developed recently for nonlinearly parameterized systems can be used to solve the problem of global output regulation, for nonlinear systems in the so-called output-feedback form with unknown parameters and exogenous signals belonging to a compact set whose bound is also unknown. 相似文献