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891.
The possibility of producing blended yarn by using one spinneret is analyzed theoretically, especially the formation of differences
in linear density and shrinkage between the monofils. Under the same spinning pressure, the die-spinning nozzles with different
diameters are used to produce the differences in the flow of the melt. According to the hagen-poseuille equation for streamline
flow in cylinder pipe, the volumetric flow rate and the mean melt speed of die-spinning nozzles increase with the increase
of diameters. Under the conditions that the winding speeds are the same, so that the effective draw ratios decrease with the
increase of the die-spinning nozzles diameters. Then, the filament formed through the die-spinning nozzle with large diameter
is coarse and have a low birefringence. On the contrary, the filament formed through the die-spinning nozzle with small diameter
is fine and have a high birefringence. The differences between the filament in structure and property could be acquired by
one spinneret. 相似文献
892.
C. W. Kan 《Fibers and Polymers》2006,7(3):262-269
In this paper, the effects of low temperature plasma (LTP) treatment on the dyeing properties of the wool fiber were studied.
The wool fibers were treated with oxygen plasma and three types of dye that commonly used for wool dyeing, namely: (i) acid
dye, (ii) chrome dye and (iii) reactive dye, were used in the dyeing process. For acid dyeing, the dyeing rate of the LTP-treated
wool fiber was greatly increased but the final dyeing exhaustion equilibrium did not show any significant change. For chrome
dyeing, the dyeing rate of the LTP-treated wool fiber was also increased but the final dyeing exhaustion equilibrium was only
increased to a small extent. In addition, the rate of afterchroming process was similar to the chrome dyeing process. For
the reactive dyeing, the dyeing rate of the LTP-treated wool fiber was greatly increased and also the final dyeing exhaustion
equilibrium was increased significantly. As a result, it could conclude that the LTP treatment could improve the dyeing behavior
of wool fiber in different dyeing systems. 相似文献
893.
Masaki Onoyama Takeshi Tsuka Tomohiro Imagawa Tomohiro Osaki Saburo Minami Kazuo Azuma Kazuhiko Kawashima Hiroshi Ishi Takahiro Takayama Nobuhiko Ogawa Yoshiharu Okamoto 《Journal of veterinary science (Suw?n-si, Korea)》2014,15(1):117-123
Sixteen cases of malignant soft tissue sarcoma (STS; 10 canines and six felines) were treated with a novel triple therapy that combined photodynamic therapy, hyperthermia using indocyanine green with a broadband light source, and local chemotherapy after surgical tumor resection. This triple therapy was called photodynamic hyperthermal chemotherapy (PHCT). In all cases, the surgical margin was insufficient. In one feline case, PHCT was performed without surgical resection. PHCT was performed over an interval of 1 to 2 weeks and was repeated three to 21 times. No severe side effects, including severe skin burns, necrosis, or skin suture rupture, were observed in any of the animals. No disease recurrence was observed in seven out of 10 (70.0%) dogs and three out of six (50.0%) cats over the follow-up periods ranging from 238 to 1901 days. These results suggest that PHCT decreases the risk of STS recurrence. PHCT should therefore be considered an adjuvant therapy for treating companion animals with STS in veterinary medicine. 相似文献
894.
Landraces of daikon, Japanese radish, Raphanus sativus var. hortensis, are grown and used traditionally in Kyushu, Japan.
These landraces are maintained by seeds harvested from selected plants which are transplanted as dormant tap roots or are
retained in a portion of field. Seeds kept in intact siliquas on the stems are harvested and stored until use, by hanging
the dried stems. Although the relatively small number of plants used in a patch for seed production might be expected to result
in a narrow base of genetic diversity of a farmers' lot in a landrace, addition of a few plants with contrasting features,
pollen exchange between household patches, and contamination from other cultivars and feral forms may save the landraces from
the rapid loss of diversity and deterioration caused by inbreeding depression. The seed production by transplanting described
in medieval Japanese literature is relatively similar to the current practice. The factors responsible for maintenance of
the landrace together with the cultural and climatic diversity of Japan may have contributed to a high diversity of landraces
of the daikon.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
895.
This study investigates the use of atmospheric pressure plasma (APP) treatment for improving surface hydrophobicity of polyurethane (PU) synthetic leather with hydrophobic organosilane precursor. The precursor was deposited on the synthetic leather surface by means of APP treatment regarded as an effective, simple, and single-step low pollution method. The result showed that under a particular combination of the experimental parameters, a hydrophobic surface was achieved on the APP treated sample with contact angle of 94 °. Moreover, the hydrophobic surface is stable for at least 30 days after APP treatment. 相似文献
896.
Shibata K Nakamura T Matsumoto T Otsuji K Okamoto TJ Nishizuka N Kawate T Watanabe H Nagata S Ueno S Kitai R Nozawa S Tsuneta S Suematsu Y Ichimoto K Shimizu T Katsukawa Y Tarbell TD Berger TE Lites BW Shine RA Title AM 《Science (New York, N.Y.)》2007,318(5856):1591-1594
The heating of the solar chromosphere and corona is a long-standing puzzle in solar physics. Hinode observations show the ubiquitous presence of chromospheric anemone jets outside sunspots in active regions. They are typically 3 to 7 arc seconds = 2000 to 5000 kilometers long and 0.2 to 0.4 arc second = 150 to 300 kilometers wide, and their velocity is 10 to 20 kilometers per second. These small jets have an inverted Y-shape, similar to the shape of x-ray anemone jets in the corona. These features imply that magnetic reconnection similar to that in the corona is occurring at a much smaller spatial scale throughout the chromosphere and suggest that the heating of the solar chromosphere and corona may be related to small-scale ubiquitous reconnection. 相似文献
897.
高校实验室是高校履行人才培养、科学研究和社会服务等职能的重要场所,高校实验室安全管理体系建设在保障师生生命安全和学校财产安全、为“双一流建设”保驾护航方面发挥着重要作用。系统分析目前高校实验室安全管理中存在的问题,并从实验室安全管理的组织体系、制度体系、防护体系、教育培训和巡查整改等维度提出新时期加强实验室安全管理体系建设的策略。 相似文献
898.
有螺滩地林农复合生态系统的建立及其效果分析 总被引:9,自引:0,他引:9
对有螺滩地林农复合生态系统的作用及其应用效果作了分析,结果表明:应用林农间种、窄株宽行、低坝高拦发展水产等技术建立的林农渔复合生态系统,不利于钉螺孳生,灭螺防病效果明显,经济效益显著。 相似文献
899.
Algae have acquired plastids by developing an endosymbiotic relationship with either a cyanobacterium (primary endosymbiosis) or other eukaryotic algae (secondary endosymbiosis). We report a protist, which we tentatively refer to as Hatena, that hosts an endosymbiotic green algal partner but inherits it unevenly. The endosymbiosis causes drastic morphological changes to both the symbiont and the host cell architecture. This type of life cycle, in which endosymbiont integration has only partially converted the host from predator to autotroph, may represent an early stage of plastid acquisition through secondary symbiosis. 相似文献
900.
The initiation of X-chromosome inactivation is thought to be tightly correlated with early differentiation events during mouse development. Here, we show that although initially active, the paternal X chromosome undergoes imprinted inactivation from the cleavage stages, well before cellular differentiation. A reversal of the inactive state, with a loss of epigenetic marks such as histone modifications and polycomb proteins, subsequently occurs in cells of the inner cell mass (ICM), which give rise to the embryo-proper in which random X inactivation is known to occur. This reveals the remarkable plasticity of the X-inactivation process during preimplantation development and underlines the importance of the ICM in global reprogramming of epigenetic marks in the early embryo. 相似文献