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许勤勤  杜红党 《轴承》2007,(8):16-17
传统的星形套外球面的磨加工工艺采用正向磨削法,其属于断续磨削且由于磨削力突变易造成振动,针对这种现象提出了斜向磨削法,提高了表面质量和加工精度。  相似文献   
2.
A strain isolated from the fruiting body of a fungus parasitized on Elaphomyces was identified as Cordyceps ophioglossoides based on the morphological characteristics and the analysis of ITS-5.8s rDNA sequence. The optimal medium composition (g•L-1), containing sucrose 66.0, yeast powder 10.0, silkworm chrysalises digest 30.0, MgSO4•7H2O 0.4, and KH2PO4 0.4, was found using fractional factorial design and a central composite design, and the optimization of cultural conditions obtained a result of seed age 6 days, inoculum size 6% (by volume), initial pH 5.6, temperature 24°C, shaking speed 160 r•min-1 by one-factor-at-a-time method. The maximum biomass reached about 20.2 g•L-1 after 90 hours culture under the optimal conditions. Elementary pharmacological activities showed that mycelia of C. ophioglossoides L2 from submerged culture promoted uterus growth in estrogen- depleted mice. In the 15-litre scale-up fermentation, the mycelial biomass was around 19.1 g•L-1, indicating a promising prospect for this biotechnology and the potency to develop its medical value.  相似文献   
3.
许勤勤  赵修同  冯万寿 《轴承》2006,(8):16-16,30
在滚道凸度插补修整技术的基础上,开发了由伺服电机通过弹性联轴器带动滚珠丝杠,由滚珠丝杠螺母带动整个金刚笔座运动的凸度插补修整微进给机构。修整微进给的刚度和精度得到了保证,同时也避免了爬行,修整器的最小进给量能稳定保持在3μm以下。  相似文献   
4.
Cordyceps ophioglossoides is a valuable traditional medicinal material.We have found that intracellular polysaccharide(IPS) is the major biologically active ingredient in Cordyceps ophioglossoides.This study is the first time to optimize the yield of IPS from Cordyceps ophioglossoides.The optimal medium for IPS production consists of glucose 54.50 g·L·1,yeast powder 25.50 g·L·1,NaH2PO4 0.4 g·L·1 and K2HPO4 0.4 g·L·1.The suggested culture conditions are 24 ℃,initial pH 4.5 with a rotary speed of 120 r·min·1 for 168 h.The yield of IPS is 737.93 mg·L·1,which is 50% higher than the yield under the conditions prior to optimization.The anti-oxidative activities of IPS in Cordyceps ophioglossoides L2 are also characterized using various in vitro assay.The anti-oxidative activity may explain the reason why IPS from Cordyceps ophioglossoides can be used to fight against neurodegenerative dis-eases and menopausal symptoms.  相似文献   
5.
A neutral metalloprotease was purified from the cultured mycelia of Laccocephalum mylittae, an effective medicinal fungus widely used in anthelmintic therapy. The protease was purified to homogeneity with 31.85-fold purification and a final yield of 21.76%. The subunit molecular weight of the protease is about 40000 estimated by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). The optimum reaction pH and temperature are 7.5 and 50ºC, respectively. The protease activity is largely enhanced by Ca2+, but highly inhibited by tetrasodium ethylenediaminetetraacetate (EDTA), a metal-chelator, suggesting that the enzyme is a metalloprotease. The Michaelis-Menten constan Km and Vmax value for casein substrate are 6.09 mg&;#8226;ml-1 and 21.32 μg&;#8226;min-1&;#8226;ml-1, respectively. In vitro anthelmintic tests of the protease exhibit distinct lethal effects on the third stage larvae (L3) of Ascaris suum. Scanning electron microscopy and SDS-PAGE analysis indicates that the proteolysis of larvae proteins caused by this protease may relate to the anthelmintic activity of L. mylittae.  相似文献   
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