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31.
针对在煤气回收和放散调试过程中发现的问题,通过改进转炉煤气回收和放散控制系统,增加气动三通阀控制联锁信号,保证放散的高度可靠性和煤气自动回收的高度安全性。  相似文献   
32.
The purpose of this article is to present an evolutionary model of the enablers and inhibitors affecting the implementation and sustainability of continuous improvement. With this aim, a qualitative study using the grounded theory was carried out. Interviews were conducted with managers responsible for continuous improvement in first‐tier suppliers in the automotive sector. As a result, two existing lines of research in the continuous improvement literature are synthesized: on one hand, the literature concerning the enablers and barriers associated with continuous improvement sustainability; and on the other, the literature concerning the evolutionary model. © 2011 Wiley Periodicals, Inc.  相似文献   
33.
对FK6-600牵伸加弹机主传动中"格里森"制圆弧螺旋齿轮的失效情况进行了考察和研究。通过对德国DIN867和我国JB110标准的分析,采用了等顶隙收缩齿并对其进行了合理改进,同时在现场安装工作中采取了必要措施,取得了较好的技术经济效果。  相似文献   
34.
D. T. Cambell and D. W. Fiske (1959) made the now-obvious statement that measures of the same variable made by different methods should agree (converge) and certainly should agree better than measures of different variables made by those several methods. Almost everyone accepted that statement, yet the multitrait–multimethod matrices published today show little or no improvement over the published examples cited in 1959. The article raised the conceptual problem of how a variable and its measurement should be linked and the methodological problem of clarifying the nature of methods and their effects. Given these unresolved problems, it is perhaps not surprising that the question of the appropriate statistical analysis of these matrices has also no consensual answer. Perhaps methods and traits or contents are so thoroughly intertwined that their interaction cannot be adequately analyzed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
35.
Tomato is one of the major vegetable crops consumed worldwide. Tomato yellow leaf curl virus (TYLCV) and fungal Oidium sp. are devastating pathogens causing yellow leaf curl disease and powdery mildew. Such viral and fungal pathogens reduce tomato crop yields and cause substantial economic losses every year. Several commercial tomato varieties include Ty-5 (SlPelo) and Mildew resistance locus o 1 (SlMlo1) locus that carries the susceptibility (S-gene) factors for TYLCV and powdery mildew, respectively. The clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated protein (Cas) is a valuable genome editing tool to develop disease-resistant crop varieties. In this regard, targeting susceptibility factors encoded by the host plant genome instead of the viral genome is a promising approach to achieve pathogen resistance without the need for stable inheritance of CRISPR components. In this study, the CRISPR/Cas9 system was employed to target the SlPelo and SlMlo1 for trait introgression in elite tomato cultivar BN-86 to confer host-mediated immunity against pathogens. SlPelo-knockout lines were successfully generated, carrying the biallelic indel mutations. The pathogen resistance assays in SlPelo mutant lines confirmed the suppressed accumulation of TYLCV and restricted the spread to non-inoculated plant parts. Generated knockout lines for the SlMlo1 showed complete resistance to powdery mildew fungus. Overall, our results demonstrate the efficiency of the CRISPR/Cas9 system to introduce targeted mutagenesis for the rapid development of pathogen-resistant varieties in tomato.  相似文献   
36.
Introduction of C4 photosynthetic traits into C3 crops is an important strategy for improving photosynthetic capacity and productivity. Here, we report the research results of a variant line of sorghum–rice (SR) plant with big panicle and high spikelet density by introducing sorghum genome DNA into rice by spike-stalk injection. The whole-genome resequencing showed that a few sorghum genes could be integrated into the rice genome. Gene expression was confirmed for two C4 photosynthetic enzymes containing pyruvate, orthophosphate dikinase and phosphoenolpyruvate carboxykinase. Exogenous sorghum DNA integration induced a series of key traits associated with the C4 pathway called “proto-Kranz” anatomy, including leaf thickness, bundle sheath number and size, and chloroplast size in bundle sheath cells. Significantly, transgenic plants exhibited enhanced photosynthetic capacity resulting from both photosynthetic CO2-concentrating effect and improved energy balance, which led to an increase in carbohydrate levels and productivity. Furthermore, such rice plant exhibited delayed leaf senescence. In summary, this study provides a proof for the feasibility of inducing the transition from C3 leaf anatomy to proto-Kranz by spike-stalk injection to achieve efficient photosynthesis and increase productivity.  相似文献   
37.
Artificial domestication and improvement of the majority of crops began approximately 10,000 years ago, in different parts of the world, to achieve high productivity, good quality, and widespread adaptability. It was initiated from a phenotype-based selection by local farmers and developed to current biotechnology-based breeding to feed over 7 billion people. For most cereal crops, yield relates to grain production, which could be enhanced by increasing grain number and weight. Grain number is typically determined during inflorescence development. Many mutants and genes for inflorescence development have already been characterized in cereal crops. Therefore, optimization of such genes could fine-tune yield-related traits, such as grain number. With the rapidly advancing genome-editing technologies and understanding of yield-related traits, knowledge-driven breeding by design is becoming a reality. This review introduces knowledge about inflorescence yield-related traits in cereal crops, focusing on rice, maize, and wheat. Next, emerging genome-editing technologies and recent studies that apply this technology to engineer crop yield improvement by targeting inflorescence development are reviewed. These approaches promise to usher in a new era of breeding practice.  相似文献   
38.
文章结合HARDINGE数控车床实例,介绍了如何利用FANUC18T数控系统中提供的计数器跟踪刀具加工的次数,通过新增一个刀具寿命管理功能模块的PMC子程序,为用户提供一个友好、可视、便捷的刀具寿命管理功能。对今后类似的设备功能设计和改进都具有实际的指导意义和参考价值。  相似文献   
39.
黄海生  胡剑斌 《轧钢》2007,37(4):78-80
针对采用带头与卷取机芯轴橡胶套筒定位区动态接触的传统自动定位技术控制效果不好而带来带头印缺陷的问题,对其产生原因进行了分析,这是因为不同规格、钢种带钢的工艺参数不同,带钢穿带过程中在传送辊上的打滑量不同,在传输通道上的下垂量不同,带头到达卷取机芯轴定位区时计算带头位置与实际带头位置存在不稳定的偏差,因此带头定位精度不稳定。为此,开发了双动态自动定位技术,穿带过程中预留了足够的带钢打滑及下垂富余量,且带头与定位区中心线在助卷皮带咬入口静止状态下接触,消除了影响带头定位精度的主要因素,带头定位精度能稳定在±15 mm的误差范围内。实际应用效果表明,该方法可行、实用。  相似文献   
40.
何晓波  田文  李庆伟  罗卫萍 《轧钢》2002,19(5):57-58
为提高型材矫直质量,防止矫后变形,对安钢小型厂300机组采取改进矫直工艺,增设矫后整形装置,改造矫直辊轴套,增设冷却水管路等措施,明显提高了角钢、槽钢的矫直质量。  相似文献   
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