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排序方式: 共有356条查询结果,搜索用时 15 毫秒
91.
Helena Rudge de Moraes Barros Tânia Aparecida Pinto de Castro Ferreira Maria Inés Genovese 《Food chemistry》2012
Four Citrus species (C. sinensis, cvs. Pera and Lima; C. latifolia Tanaka cv. Tahiti; C. limettioides Tanaka cv. Sweet lime and C. reticulate, cv. Ponkan) grown in Brazil were characterised in relation to contents of minerals, ascorbic acid, total polyphenols and antioxidant capacity of pulps and peels. In general, the peels demonstrated significantly higher contents of all compounds than the pulps (p < 0.05), with the exception of the Pera orange pulp that presented the highest acid ascorbic content (68 mg/100 ml), while the Tahiti lime peel presented the lowest (8 mg/100 g). Citrus showed high levels of potassium, calcium and magnesium, and the peels were considered sources of these minerals. The Ponkan mandarin peel presented the highest antioxidant capacity. The antioxidant capacity of citrus was correlated both to vitamin C and phenolics. Aside from citrus pulps, the peels are also good sources of bioactive compounds and minerals, and can be explored for their health promoting values in food products. 相似文献
92.
Full‐field optical measurements like digital image correlation or the grid method have brought a paradigm shift in the experimental mechanics community. While inverse identification techniques like finite element model updating or the virtual fields method have been the object of significant developments, current test methods, inherited from the age of strain gauges or linear variable displacement transducers, are generally not well adapted to the rich information provided by these new measurement tools. This paper provides a review of the research dealing with the design and optimization of heterogeneous mechanical tests for the identification of material parameters from full‐field measurements, christened here Material Testing 2.0 (MT2.0). 相似文献
93.
Quantitative Analysis of Multiple Proteins of Different Invasive Tumor Cell Lines at the Same Single‐Cell Level
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Xiangchun Zhang Ru Liu Qingming Shu Qing Yuan Gengmei Xing Xueyun Gao 《Small (Weinheim an der Bergstrasse, Germany)》2018,14(17)
Tumor cell invasion is pivotal to the development, metastasis, and prognosis of tumors. It is reported that the invasive ability of tumor cells is mainly dependent on the expression levels of membrane type‐1 matrix metalloproteinase (MT1‐MMP) and integrin αVβ3 proteins on cell membranes. To precisely distinguish between tumor cells with different invasive abilities, it is important to establish a highly sensitive and precise quantification method to differentiate the expression levels of MT1‐MMP and integrin αVβ3 in the same single tumor cell at the same time. Herein, two functional peptides to construct red‐emissive Au26 clusters and green‐emissive Ag12 clusters are reported. Moreover, the Au26 clusters and Ag12 clusters have the ability to specifically target MT1‐MMP and integrin αVβ3, respectively, in the same single cell at the same time. By utilizing the fluorescent properties and metallic compositions of metal clusters, the MT1‐MMP and integrin αVβ3 levels of the more invasive SiHa cells or the less invasive HeLa cells are simultaneously and quantitatively differentiated via laser ablation inductively coupled plasma mass spectrometry. This method of quantitatively detecting multiple invasive proteins on the same cell is of great value for accurately diagnosing aggressive tumors and monitoring the invasiveness of these tumors. 相似文献
94.
介绍了以单片机AT89S52和DTMF信令解码芯片MT8870为核心,通过PSTN电话网络远程遥控煤矿井下安全警示系统的工作原理。从硬件接口和软件设计两方面阐述了铃流检测、模拟摘挂机、DTMF信令解码、密码检测、输入信号分析处理等功能的实现方法。 相似文献
95.
介绍数字式CMOS摄像头MT9M011的工作方式;提出MT9M011在基于HCS12单片机的智能车控制系统中的应用方案,针对采集图像时遇到的问题给出了相应的解决方法;分析数字式CMOS摄像头相对于模拟摄像头的优势和不足。 相似文献
96.
MT及CSAMT方法在城市地热资源勘探中的应用 总被引:1,自引:0,他引:1
城市地热资源勘探的过程中诸多干扰因素的存在,严重制约了各种物探方法的应用,选择既能抗干扰又能保证勘探深度的方法是解决问题的关键.CSAMT抗干扰能力较强,对浅部不均匀体有较细致的刻画,MT方法对深部构造有较高的分辨率,利用前者资料对后者曲线首支进行解释并做综合反演,能较好地解决这一难题.结合某开发区地热资源勘探的实例,说明在电磁干扰较大的城区通过两种方法联合勘探,并利用其综合反演成果来推断以低阻为表现特征的热储层深度是行之有效的。 相似文献
97.
98.
根据电话监测与监管的要求,通过反复的实验和分析,设计了基于MT8888的电话监测系统,系统利用MT8888实现监听并线电话的主叫号码,并进行主叫状态的检测,另外,上位机还可以发送控制指令拔打指定号码。该监测系统改进了DTMF输出信号耦合电路,通过高效的软件控制,并结合摘挂机检测与模拟摘挂机电路,使系统在拨号之后能快速有效地进行回铃、忙音等主叫状态的检测。 相似文献
99.
地铁列车乘客紧急报警系统设计 总被引:1,自引:0,他引:1
赵晓峰 《单片机与嵌入式系统应用》2011,11(6):49-51,55
在地铁列车乘客紧急报警系统的设计过程中,采用AT89C52实现主控制逻辑,报警主机和分机之间的通信使用基于MT8888的DTMF通信,并使用EPM1270实现CRC8算法,提高了通信的安全性和可靠性。该系统具有存储功能,利用自行设计的键盘可实现格式化存储器。 相似文献
100.
In order to analyze the thermal decomposition of MT based pyrolant in nitrogen and air environments,the thermal analysis experiments of MT and MTV pyrolants were carried out by TG-DTA and DSC.The results show that,in nitrogen environment,the spectrum result of Grignard-type reaction~[6] is verified by the decomposition characteristics of MT and MTV pyrolants.8.71% of Mg is consumed in the intermediate reaction of MT at 500-596 ℃ and the heat release of reaction is 31.93 k J/g.The endothermic decomposition of the intermediate product is at 684-740 ℃.In MTV,the intermediate reaction is at 435-595 ℃ and the heat release of reaction are increased by the addition of fluororubber.The intermediate product degrades at 677-745 ℃.In air environment,the decomposition of MT and MTV show the different reaction mechanism from the nitrogen environment.The presence of oxygen is involved in the reaction of Mg,and inhibits the intermediate reaction process of Mg and PTFE. 相似文献