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11.
A. W. MacGregor 《Journal of the Institute of Brewing》1996,102(2):97-102
Molecular technologies have been developed for the transformation of barley. These technologies complement current methods of barley breeding. In addition, they offer the potential of altering specific components in barley that affect malting quality and of introducing foreign genes, controlling desirable traits, into barley. Application of genetic engineering to improving malt quality factors such as cell wall degradation, protein modification, starch hydrolysis and flavour stability, is discussed. Limitations to the use of this technology for improving malt-related functional properties of barley components such as cell walls and starch granules are also evaluated. Some possible constraints to the utilization of genetic engineering for malt quality improvements are identified. 相似文献
12.
Yuelei Zhao Sheng Yang Kai Wu Shuang Li Yang Gao Hongyuan Hao Xichao Zhang Shouguo Wang Qingfang Liu Senfu Zhang Zhiqin Chu Johan Åkerman Yan Zhou 《Advanced functional materials》2023,33(49):2303133
Synthetic antiferromagnetic (SAF) skyrmions are emerging as novel information carriers due to their high mobility and lack of a skyrmion Hall effect. However, distinguishing SAF skyrmions from their ferromagnetic counterparts using imaging techniques like magneto-optical microscopy remains challenging. While the suppressed intrinsic skyrmion Hall effect (SkHE) has been commonly used to identify SAF skyrmions, it is important to note that other factors such as defect pinning and dipolar interaction can also lead to a suppressed SkHE. Therefore, there is an urgent need for a universal identification method that can reliably differentiate SAF skyrmions from ferromagnetic ones. In this study, the generation of a SAF skyrmion within a standard SAF stack is demonstrated and its motion with almost no SkHE is investigated. Furthermore, a universal identification method is proposed wherein the application of an out-of-plane field allows the SAF skyrmion to be decoupled into two domains, which can either expand or contract with the application of an electric current. By expediting the development of a reliable means of identifying SAF skyrmions, these findings will accelerate the realization of practical applications based on these unique information carriers. 相似文献
13.
Mathias Schröder Alexander Haußmann Andreas Thiessen Elisabeth Soergel Theo Woike Lukas M. Eng 《Advanced functional materials》2012,22(18):3936-3944
Ferroic materials play an increasingly important role in novel (nano)electronic devices. Recently, research on domain walls (DWs) receives a big boost by the discovery of DW conductivity (DWC) in BiFeO3 and Pb(ZrxTi1‐x)O3 ferroic thin films. Here, it is demonstrated that DWC is not restricted to thin films, but equally applies to millimeter‐thick wide‐bandgap, ferroic single crystals, such as LiNbO3. In this material transport along DWs can be switched by super‐bandgap illumination and tuned by engineering the tilting angle of DWs with respect to the polar axis. The results are consistently obtained using conductive atomic force microscopy to locally map the DWC and macroscopic contacts, thereby in addition investigating the temperature dependence, DW transport activation energies, and relaxation behavior. 相似文献
14.
Tae Heon Kim Byung Chul Jeon Taeyoon Min Sang Mo Yang Daesu Lee Yong Su Kim Seung‐Hyub Baek Wittawat Saenrang Chang‐Beom Eom Tae Kwon Song Jong‐Gul Yoon Tae Won Noh 《Advanced functional materials》2012,22(23):4962-4968
It is demonstrated that electric transport in Bi‐deficient Bi1‐δFeO3 ferroelectric thin films, which act as a p‐type semiconductor, can be continuously and reversibly controlled by manipulating ferroelectric domains. Ferroelectric domain configuration is modified by applying a weak voltage stress to Pt/Bi1‐δFeO3/SrRuO3 thin‐film capacitors. This results in diode behavior in macroscopic charge‐transport properties as well as shrinkage of polarization‐voltage hysteresis loops. The forward current density depends on the voltage stress time controlling the domain configuration in the Bi1‐δFeO3 film. Piezoresponse force microscopy shows that the density of head‐to‐head/tail‐to‐tail unpenetrating local domains created by the voltage stress is directly related to the continuous modification of the charge transport and the diode effect. The control of charge transport is discussed in conjunction with polarization‐dependent interfacial barriers and charge trapping at the non‐neutral domain walls of unpenetrating tail‐to‐tail domains. Because domain walls in Bi1‐δFeO3 act as local conducting paths for charge transport, the domain‐wall‐mediated charge transport can be extended to ferroelectric resistive nonvolatile memories and nanochannel field‐effect transistors with high performances conceptually. 相似文献
15.
Okokon U Etokakpan 《Journal of the science of food and agriculture》1993,61(4):389-393
β-(1·3)(1·4)-Glucans are the major components of isolated endosperm cell walls of both sorghum and barley grains and the concentration declines from 75% in unmalted barley walls to 32% in those of the 6-day malts. In sorghums over the same period, the reduction was from 72 and 68% to 54 and 62% in varieties L187 and SK5912, respectively. Following germination wall pentosans, while enhanced in barley, decreased in sorghum. The enzymes which were unable to hydrolyse the walls of sorghum to release sugars (unlike those of barley) did so after the walls had been solubilised in alkali. Cellobiose accounted for 43% of the hydrolysates of the alkali-solubilised walls when incubated with sorghum malt enzymes and 79% when barley enzymes were used. Laminaribiose was not detected in either case which indicates that the polysaccharide of the sorghum walls is largely of a ‘cellulosic’ nature. Preliminary evidence suggests that fuco-xyloglucan may contribute to the resistance of the sorghum endosperm cell walls to enzymic attack during germination. 相似文献
16.
邹定华 《土木与环境工程学报》2011,33(6):124-128
建筑外墙传热性能现场检测是建筑节能检验的重点与难点,目前的检测方法难以得出较为准确的结果。针对以上问题,提出了采用热箱加热流计的检测方法以及该方法的误差评价方法,并运用计算机模拟的手段分析了热箱尺寸、温度制度、墙体构造、墙体厚度对该方法检测结果误差的影响,指出影响误差的主要因素是热箱尺寸和墙体厚度。根据模拟试验结果进行了现场检测试验,证明热箱加热流计的检测结果有良好的精度。 相似文献
17.
18.
我国油田正面临井网的三次加密,开采对象是一次加密和二次加密未动用的所有油层,二次加密后的剩余油决定了三次加密的不均匀性,且在层系上不具有独立性。聚合物驱的井网开发过后,还有相当一部分油层未能进行三次采油,有必要进一步开发。分析了三次加密和三次采油单独开采的缺陷,介绍二者结合的可能方法,并通过数模对各种可能的结合方法进行模拟,结果证明三次加密与三次采油相结合是可行的,更有利于提高油田的采收率和开发效果。 相似文献
19.
20.
本文给出了一种能够传输均匀场的介质壁矩形波导,在数值计算的基础上得出了其结构参数;并进一步分析了加载工作物质对其场型的影响。 相似文献