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91.
This article presents the results of investigations on the pulverizing grinding energy requirements for whole and preliminary ground wheat kernels regarding different moisture levels. Four common wheat cultivars (Triticum aestivum, ssp. vulgare) differing in kernel hardness were used for tests. When the moisture of kernels ranged from 14% to 20% w.b. the lower values of average particle size were obtained for preliminary ground wheat. The pulverizing energy requirements expressed by different grinding indices were considerably lower for preliminary ground kernels rather than for whole kernels. The values of specific pulverizing energy ranged from 32.6 to 79.0 kJ kg−1 for whole kernels, whereas the values of total specific grinding energy (the sum of specific grinding energy and specific pulverizing energy) changed from 23.1 to 44.4 kJ kg−1 for the two-stage ground wheat. In addition, the other values of pulverizing indices confirmed that preliminary size reduction significantly reduced the grinding energy requirements.  相似文献   
92.
Highly transparent X2O3 sesquioxide ceramics were obtained from a solid solution of five different oxides (Lu2O3, Y2O3, Yb2O3, Gd2O3, and Dy2O3), mixed in an equal molar ratio according to the principle of high-entropy. The fabricated (Lu, Y, Yb, Gd, Dy)2O3 ceramics achieved 99.97 % of the relative density and exhibited a high degree of optical transparency with the in-line transmittance of almost 80 % in the visible wavelength range. Emissions of Gd3+ (6PJ8S7/2 at 312 nm), Dy3+ (4F9/26H15/2 at 492 nm and 4F9/26H13/2 at 572 nm), and Yb3+ (2F5/22F7/2 at 1031 nm) suggested a potential application of the high-entropy ceramics as multi-wavelength emission phosphor transparent ceramics. High-entropy ceramics also exhibited lower specific heat and thermal conductivity compared to single-element sesquioxide ceramics. This work demonstrated that highly transparent oxide ceramics, with complex chemical compositions and good optical properties, could be obtained using the high-entropy principle.  相似文献   
93.
Opioids are the drugs of choice in severe pain management. Unfortunately, their use involves serious, potentially lethal side effects. Therefore, efforts in opioid drug design turn toward safer and more effective mechanisms, including allosteric modulation. In this study, molecular dynamics simulations in silico and ‘writhing’ tests in vivo were used to characterize potential allosteric mechanism of two previously reported compounds. The results suggest that investigated compounds bind to μ opioid receptor in an allosteric site, augmenting action of morphine at subeffective doses, and exerting antinociceptive effect alone at higher doses. Detailed analysis of in silico calculations suggests that first of the compounds behaves more like allosteric agonist, while the second compound acts mainly as a positive allosteric modulator.  相似文献   
94.
95.
Metallurgical and Materials Transactions A - The reduction of freckle defect in the single-crystal blade root by controlling local cooling conditions was investigated. Application of the IRBs...  相似文献   
96.
Sexually transmitted infections (STIs) caused by Neisseria gonorrhoeae, Chlamydia trachomatis and Mycoplasma genitalium are a common cause of pelvic inflammatory disease (PID) which can lead to tubal factor infertility (TFI). TFI is one of the most common causes of infertility, accounting for 30% of female fertility problems. STIs can also have an impact on pregnancy, leading to adverse pregnancy outcomes. Escalating antibiotic resistance in Neisseria gonorrhoeae and Mycoplasma genitalium represents a significant problem and can be therapeutically challenging. We present a comprehensive review of the current treatment options, as well as the molecular approach to this subject. We have given special attention to molecular epidemiology, molecular diagnostics, current and new treatments, and drug resistance.  相似文献   
97.
Meat is an excellent source of protein with a good balance of amino acids. It is also rich in several minerals, vitamins and bioactive compounds, which play important roles in metabolism and are easily assimilated from meat compared with other foods. The nutritional value of meat is one of the factors that influence consumer acceptance. However, it can be significantly reduced during processing. Moreover, some operations, such as curing, smoking or fermentation, used for processing can lead to the formation of harmful components in meat, and hence, nutritionists associate high consumption of processed meat with an increased risk of several diseases such as cardiovascular disorders and cancers. This review deals with the distinctive aspects of the technological strategies that can be used to improve the nutritional value of meat products, including the incorporation of bioactive components, reduction or elimination of harmful components (e.g. nitrite/nitrate, fat) and alternative technologies (ultrasound).  相似文献   
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99.
This study demonstrates new possibilities in using freeze‐dried buckwheat sourdoughs in the processing of gluten‐free bread (GFB). Fresh and freeze‐dried (at temperatures of 20, 40 and 60 °C) sourdoughs were added in the amounts of 10, 20, 30 and 40% of the total flour content. Significant and beneficial changes in the quality of bread under the influence of different quantities of fresh and freeze‐dried sourdoughs additive were observed. Freeze‐dried buckwheat sourdoughs at the level of 20 and 30% gave the best baking results for GFB. pH of bread significantly changed, which had a positive effect on increasing its suitability for the storage. Buckwheat sourdough dried at 40 °C is the most highly recommended for GFB processing. Higher temperatures (60 °C) caused the least change in bread volume; however, a bitter aftertaste from burning was slightly detectable. Freeze‐dried buckwheat sourdoughs can be used directly in processing, thus eliminating the long fermentation of sourdough.  相似文献   
100.
Multiferroics with negative value of dielectric constant are very promising materials because of their modern applicability. These materials can be used as materials for the construction of electromagnetic radiation shields. The subject of the research is multiferroic BiFeO3–PbFe1/2Nb1/2O3 (BF–PFN) ceramics. For all multiferroic materials the following studies are conducted: SEM, EDS and the temperature dependence of dielectric constant ε′(T). Above a certain temperature (different for different chemical compositions) the value of dielectric constant reaches negative values. Such the behavior of the dielectric constant may indicate that the polarization inside the material has a reverse direction to the external electric field. That is, the electric field inside the material counteracts the applied external electric field. The obtaining materials also show negative dielectric losses. The Axelrod model is used to explain the mechanism that causes negative dielectric loss.  相似文献   
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