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71.
《Ceramics International》2022,48(8):10885-10894
Lead-free bismuth sodium titanate-strontium titanate (NBT-ST) dielectric ceramic materials have been extensively investigated energy storage materials because of their relaxor characteristics. In this study, four different lanthanide elements were introduced into the ferroelectric NBT-ST ceramic to improve their relaxor properties. The introduction of the lanthanide resulted in an increase in disorder at location A within the perovskite lattice and improved relaxor characteristics, leading to a stored energy density of more than 3.5 J/cm3. In particular, an ultrahigh recoverable stored energy density of 4.94 J/cm3 and efficiency of 88.45% were achieved at 440 kV/cm when the NBT-ST ceramic was modified with neodymium. The modified ceramic also exhibited good thermal stability in the range of 30–120 °C, as well as a fast discharge time of ~153 ns, indicating that Nd-incorporated NBT-ST is a promising candidate for electrical energy storage ceramic. 相似文献
72.
One of the major challenges in wireless body area networks (WBANs) is sensor fault detection. This paper reports a method for the precise identification of faulty sensors, which should help users identify true medical conditions and reduce the rate of false alarms, thereby improving the quality of services offered by WBANs. The proposed sensor fault detection (SFD) algorithm is based on Pearson correlation coefficients and simple statistical methods. The proposed method identifies strongly correlated parameters using Pearson correlation coefficients, and the proposed SFD algorithm detects faulty sensors. We validated the proposed SFD algorithm using two datasets from the Multiparameter Intelligent Monitoring in Intensive Care database and compared the results to those of existing methods. The time complexity of the proposed algorithm was also compared to that of existing methods. The proposed algorithm achieved high detection rates and low false alarm rates with accuracies of 97.23% and 93.99% for Dataset 1 and Dataset 2, respectively. 相似文献
73.
图像纹理增强过程中容易丢失平滑区域纹理细节,而分数阶微分增强虽然能够非线性保留平滑区域纹理细节,但对频率分辨率敏感。针对这个问题,提出一种基于小波变换的分数阶微分纹理增强算法,应用于平扫计算机断层扫描(CT)图像的肝脏肿瘤区域的纹理增强。首先,通过小波变换将图像感兴趣区分解成多个子带分量;其次,基于分数阶微分定义构造一个带补偿参数的分数阶微分掩膜;最后,使用该掩膜与每个高频子带分量进行卷积并利用小波逆变换重组图像感兴趣区。实验结果表明,该方法在使用较大分数阶次显著增强肿瘤区域的高频轮廓信息的同时,有效地保留了低频平滑的纹理细节:增强后的肝细胞癌区域与原区域相比,信息熵平均增加36.56%,平均梯度平均增加321.56%,平均绝对差值平均为9.287;增强后的肝血管瘤区域与原区域相比,信息熵平均增加48.77%,平均梯度平均增加511.26%,平均绝对差值平均为14.097。 相似文献
74.
对赤红球菌的组氨酸激酶基因进行密码子优化,将优化后的组氨酸激酶基因(rhks)构建重组表达质粒pGEX-4T-2-rhks。将此质粒导入到大肠杆菌BL21(DE3)中进行异源表达。在25 ℃和1 mmol/L异丙基-β-D-硫代吡喃半乳糖苷诱导条件下,组氨酸激酶融合蛋白(GST-RHK)获得成功表达,并具有催化活性。经谷胱甘肽琼脂糖亲和层析纯化,获得电泳纯的GST-RHK,其中纯化倍数为3.1,得率为19.5%。该蛋白大小约为72.75 kDa,Km、Vmax和Kcat值分别为20.92 μmol/L、0.17 μmol/(L·min)和1.4 min-1。野生型赤红球菌、组氨酸激酶基因增强株sdrhkE和组氨酸激酶基因敲减株sdrhkD在分别含有苯酚、甲苯、氯苯、异辛烷4 种有机溶剂的培养基中培养,菌株sdrhkD的生长情况都优于野生型赤红球菌,菌株sdrhkE的生长情况都低于野生型赤红球菌。本研究为进一步揭示赤红球菌SD3中组氨酸激酶涉及的信号转导途径与赤红球菌有机溶剂耐受性的关联机制提供一定参考依据。 相似文献
75.
Lorenzo Zallocco Laura Giusti Maurizio Ronci Andrea Mussini Marco Trerotola Maria Rosa Mazzoni Antonio Lucacchini Laura Sebastiani 《International journal of molecular sciences》2021,22(9)
The autonomic nervous system (ANS) plays a crucial role both in acute and chronic psychological stress eliciting changes in many local and systemic physiological and biochemical processes. Salivary secretion is also regulated by ANS. In this study, we explored salivary proteome changes produced in thirty-eight University students by a test stress, which simulated an oral exam. Students underwent a relaxation phase followed by the stress test during which an electrocardiogram was recorded. To evaluate the effect of an olfactory stimulus, half of the students were exposed to a pleasant odor diffused in the room throughout the whole session. Saliva samples were collected after the relaxation phase (T0) and the stress test (T1). State anxiety was also evaluated at T0 and T1. Salivary proteins were separated by two-dimensional electrophoresis, and patterns at different times were compared. Spots differentially expressed were trypsin digested and identified by mass spectrometry. Western blot analysis was used to validate proteomic results. Anxiety scores and heart rate changes indicated that the fake exam induced anxiety. Significant changes of α-amylase, polymeric immunoglobulin receptor (PIGR), and immunoglobulin α chain (IGHA) secretion were observed after the stress test was performed in the two conditions. Moreover, the presence of pleasant odor reduced the acute social stress affecting salivary proteome changes. Therefore, saliva proteomic analysis was a useful approach to evaluate the rapid responses associated to an acute stress test also highlighting known biomarkers. 相似文献
76.
77.
78.
Yumio Yato 《Journal of Nuclear Science and Technology》2019,56(4):311-316
When UF6 is handled in leak tight system, the amount of uranium compound formed on the surface of containers, valves, and others in UF6 handling facilities is not so significant for a short term that special attention has not been given to this problem. The present work was done to throw some more light on this problem based on the recent experiment. We discuss the possibility that the intermolecular transfer of a fluorine atom from UF6 to UF5 may participate in the formation of uranium compound. The discussion includes also the unique features contained in the experimental result, the reaction processes assumed in this problem, and the derivation of a rate equation for expressing the deposition of uranium compound. Furthermore, we propose a new method for determining nonlinear parameters included in a governing differential equation having two variables for expressing the deposition of uranium compound from experimental raw data. 相似文献
79.
以转基因水稻中最常用的CaMV35S启动子、NOS终止子、Cry1Ab/Ac基因、HPT基因及SPS水稻内标基因为研究对象,利用5 种不同的荧光信号(FAM、HEX、Taxas Red、Cy5、Cy5.5)进行多重实时聚合酶链式反应(real-time polymerase chain reaction,real-time PCR)检测方法的研究。通过引物组合筛选、反应体系优化、特异性测试、灵敏度测试、适用性测试等一系列实验,建立了5 重real-time PCR方法,灵敏度可达0.032%。此方法具有灵敏度高、结果准确、通量大等优点,可实现水稻中转基因成分的快速、高效检测。 相似文献
80.
王文宇 《信息安全与通信保密》2021,(2)
个人信息因其自身携带隐私特性,与每个个体息息相关。个人信息保护不当,影响公众权益、企业利益以及社会秩序。在互联网、大数据、5G万物互联的时代,个人信息被广泛收集和使用,必须妥善解决个人信息保护问题,才能保障整个数据产业健康发展。而现有的个人信息保护方法或技术,不足以应对新形势下的保护诉求。基于数据运营安全的个人信息保护,针对当前个人信息保护的新形势和新诉求,提出结合人工智能,通过数据运营安全对结构化、半结构化、非结构化的个人信息流动的保护,涵盖从生产到运维,从采集、传输、存储、处理、分析、共享、销毁全生命周期保护,深入数据运营中内嵌防护,同时与业务解耦,达到保护个人信息安全的目标。 相似文献