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11.
Seery Mark D.; Holman E. Alison; Silver Roxane Cohen 《Canadian Metallurgical Quarterly》2010,99(6):1025
Exposure to adverse life events typically predicts subsequent negative effects on mental health and well-being, such that more adversity predicts worse outcomes. However, adverse experiences may also foster subsequent resilience, with resulting advantages for mental health and well-being. In a multiyear longitudinal study of a national sample, people with a history of some lifetime adversity reported better mental health and well-being outcomes than not only people with a high history of adversity but also than people with no history of adversity. Specifically, U-shaped quadratic relationships indicated that a history of some but nonzero lifetime adversity predicted relatively lower global distress, lower self-rated functional impairment, fewer posttraumatic stress symptoms, and higher life satisfaction over time. Furthermore, people with some prior lifetime adversity were the least affected by recent adverse events. These results suggest that, in moderation, whatever does not kill us may indeed make us stronger. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
12.
Rosa López Isabel López‐Alfaro Ana Rosa Gutiérrez Carmen Tenorio Patrocinio Garijo Lucía González‐Arenzana Pilar Santamaría 《International Journal of Food Science & Technology》2011,46(11):2373-2381
Malolactic fermentation (MLF) of Tempranillo Rioja wines (Spain) inoculated with two lactic acid bacteria (LAB) strains were studied and compared with spontaneous MLF. Inoculation with selected Oenococcus oeni lyophila shortened MLF duration up to 19 days and lead to wines with more fresh and fruity characters, especially when implantation was 100%. We demonstrated modifications in the concentration of volatile and nitrogenous compounds and a good correlation between analytical and sensory attributes was also noted. In addition, the low initial amino acid concentration and the consumption of these compounds by the inoculated yeast strain during alcoholic fermentation resulted in wines with very low biogenic amines levels (under 3.75 mg L?1) after MLF and 3 month storage period in all cases. The results showed the significance of choose the most suitable starter to elaborate quality wines and suggest the control of amino acid content in must and wine to prevent the formation of biogenic amines. 相似文献
13.
In order to obtain an effective and reliable grain refiner for Mg-Al alloys, 1% (mass fraction) Mg3N2 was added into AZ31 Mg alloy. The microstructures of the Mg alloys were studied by optical microscopy, scan electron microscopy and X-ray energy dispersive spectroscopy, and the mechanical properties were determined. The results show that adding a small amount of Mg3N2 to AZ31 Mg alloy can refine the grain size from 103 to 58 μm. The ultimate tensile strength and elongation of AZ31 Mg alloy are 174.1MPa and 8.3%, respectively. After the addition of 1% Mg3N2, the ultimate tensile strength and elongation of AZ31 Mg alloy are increased up to 198.7 MPa and 11.8%, respectively. The grain refinement mechanism is that AIN is formed after Mg3N2 is added. Both AIN and Mg phases are of HCP lattice structure, and the disregistry between Mg phases and AIN along (0001)Mg//(0001)AIN is 3.04%, which is very effective for heterogeneous nucleation. 相似文献
14.
《International Journal of Cast Metals Research》2013,26(4):242-247
AbstractThe viability of grain refining phosphorus deoxidised, high residual phosphorus Cu (DHP-Cu) by particle inoculation through the formation of in situ Zr, Ti, Nb, La, Ce, Gd and Nd oxide particles, additions of WC and NbB2 particles as well as additions of Ti+B, Zr+B, Al+B and Ca+B with the purpose of forming in situ boride particles have been investigated under TP-1 casting conditions. Nominal additions of P in the range of 300–690?wt?ppm and of Ag of 150?wt?ppm have also been explored. In comparison, it appears that it is more difficult to grain refine DHP-Cu by particle inoculation than it is by the combined addition of P+Ag solute elements to a residual content of 396?ppm P and 143?ppm Ag (and having very low contents of Ti, Zr, Al, Ca and B microalloying elements) for the conditions studied. 相似文献
15.
O. O. Olufajo 《Nutrient Cycling in Agroecosystems》1990,25(2):93-100
Field trials were conducted at Samaru, Nigeria over a three-year period (1986–88) to study the effects of N and P fertilization on the response of promiscuously nodulating soybean toBradyrhizobium japonicum inoculation in a ferruginous tropical soil. Phosphorus fertilization enhanced nodulation, while N fertilization had no consistent effect on nodulation. Both N and P increased dry matter production. Seed yields were not influenced by the application of N. However, P increased seed yields in two out of three years. Response of seed yield to P fertilization was significant up to 26.4 kg P ha–1.Bradyrhizobium inoculation consistently enhanced nodulation while it increased seed yield in only one out of three years. Results demonstrate that P is an important nutrient for soybean production in ferruginous tropical soils. The roles of promiscuously nodulating soybean in the maintenance of tropical soil fertility are discussed. 相似文献
16.
介绍了汽车铸件的结构以及技术要求,根据技术要求将球化处理后的化学成分控制在:w(C)3.6%~3.8%,w(Si)2.6%~2.9%,w(Mn)0.25%~0.45,w(P)≤0.030%,w(S)≤0.015%,w(Mg残)0.03%~0.04%,w(RE残)0.01%~0.02%,采用5 t中频炉熔炼,原铁液出炉温度控制在1 480~1 520℃,采用冲入法进行球化处理,选用低RE的FeSiMg6RE2球化剂,粒度为10~25mm,加入量为每包铁液量的1.1%;采用粒度为3~8 mm的CaBa复合孕育剂进行一次孕育,浇注时使用粒度为0.3~1 mm的高CaBa复合孕育剂进行二次随流孕育。最终生产铸件的球化等级控制在2~3级,石墨球大小6级,抗拉强度不低于600MPa,伸长率不低于10%,且珠光体体积分数及力学性能波动均在10%以内。 相似文献
17.
Liu Jincheng 《中国铸造》2014,(4):339-350
The demands for improved engine performance,fuel economy,durability,and lower emissions provide a continual challenge for engine designers.The use of Compacted Graphite Iron(CGI)has been established for successful high volume series production in the passenger vehicle,commercial vehicle and industrial power sectors over the last decade.The increased demand for CGI engine components provides new opportunities for the cast iron foundry industry to establish efficient and robust CGI volume production processes,in China and globally.The production window range for stable CGI is narrow and constantly moving.Therefore,any one step single addition of magnesium alloy and the inoculant cannot ensure a reliable and consistent production process for complicated CGI engine castings.The present paper introduces the SinterCast thermal analysis process control system that provides for the consistent production of CGI with low nodularity and reduced porosity,without risking the formation of flake graphite.The technology is currently being used in high volume Chinese foundry production.The Chinese foundry industry can develop complicated high demand CGI engine castings with the proper process control technology. 相似文献
18.
立式静态固态发酵罐的研制 总被引:1,自引:0,他引:1
介绍了一种新型立式静态固态物料发酵罐的结构特点及工作原理,对灭菌、接种、通气等关键生产工序进行了探讨。经多批次纤维素酶的培养试验,结果表明,立式静态固态物料发酵罐实现了产生蒸气,直接对固态物料进行蒸气灭菌、冷却、接种、发酵、无菌空气的供给,杜绝杂菌污染,降低了设备造价,提高了性价比,提高了产品的产量和质量。 相似文献
19.
Viana F Belloch C Vallés S Manzanares P 《International journal of food microbiology》2011,151(2):235-240
The effect of simultaneous or sequential inoculation of Hanseniaspora vineae CECT 1471 and Saccharomyces cerevisiae T73 in non-sterile must on 2-phenylethyl acetate production has been examined. In both treatments tested, no significant differences in Saccharomyces yeast growth were found, whereas non-Saccharomyces yeast growth was significantly different during all days of fermentation. Independently of the type of inoculation, S. cerevisiae was the predominant species from day 3 till the end of the fermentation. The dynamics of indigenous and inoculated yeast populations showed H. vineae to be the predominant non-Saccharomyces species at the beginning of fermentation in sequentially inoculated wines, whereas the simultaneous inoculation of S. cerevisiae did not permit any non-Saccharomyces species to become predominant. Differences found in non-Saccharomyces yeast growth in both fermentations influenced the analytical profiles of final wines and specifically 2-phenylethyl acetate concentration which was two-fold increased in sequentially inoculated wines in comparison to those co-inoculated. In conclusion we have shown that H. vineae inoculated as part of a sequential mixed starter is able to compete with native yeasts present in non-sterile must and modify the wine aroma profile. 相似文献
20.