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31.
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Yong Pan Chen Zhu Wen Bin Zeng Pei Fu Chi Chen Bao Ming Xu Zhong Feng Gao 《Chembiochem : a European journal of chemical biology》2021,22(24):3431-3436
Rapid and sensitive point-of-care testing (POCT) is an extremely critical mission in practical applications, especially for rigorous military medicine, home health care, and in the third world. Here, we report a visual POCT method for adenosine triphosphate (ATP) detection based on Taylor rising in the corner of quadratic geometries between two rod surfaces. We discuss the principle of Taylor rising, demonstrating that it is significantly influenced by contact angle, surface tension, and density of the sample, which are controlled by ATP-dependent rolling circle amplification (RCA). In the presence of ATP, RCA reaction effectively suppresses Taylor-rising behavior, due to the increased contact angle, density, and decreased surface tension. Without addition of ATP, untriggered RCA reaction is favorable for Taylor rising, resulting in a significant height. With this proposed method, visual sensitive detection of ATP without the aid of other instruments is realized with only a 5 μL droplet, which has good selectivity and a low detection limit (17 nM). Importantly, this visual method provides a promising POCT tool for user-friendly molecular diagnostics. 相似文献
33.
Zhen Wu Jing Yao Pengfei Zhu Fusheng Yang Xiangyu Meng Sandra Kurko Zaoxiao Zhang 《International Journal of Hydrogen Energy》2021,46(19):11183-11198
Advanced biogas power generation technology has been attracting attentions, which contributes to the waste disposal and the mitigation of greenhouse gas emissions. This work proposes and models a novel biogas-fed hybrid power generation system consisting of solid oxide fuel cell, water gas shift reaction, thermal swing adsorption and proton exchange membrane fuel cell (SOFC-WGS-TSA-PEMFC). The thermodynamic, exergetic, and thermo-economic analyses of this hybrid system for power generation were conducted to comprehensively evaluate its performance. It was found that the novel biogas-fed hybrid system has a gross energy conversion efficiency of 68.63% and exergy efficiency of 65.36%, indicating high efficiency for this kind of hybrid power technology. The market sensitivity analysis showed that the hybrid system also has a low sensitivity to market price fluctuation. Under the current subsidy level for the distributed biogas power plant, the levelized cost of energy can be lowered to 0.02942 $/kWh for a 1 MW scale system. Accordingly, the payback period and annual return on investment can reach 1.4 year and about 20%, respectively. These results reveal that the proposed hybrid system is promising and economically feasible as a distributed power plant, especially for the small power scale (no more than 2 MW). 相似文献
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The support flux was first investigated as a separate influencing factor for its effect on performances of ceramic filtration membranes. Three pre-membranes were prepared by tape-casting and then transfer-coated to supports to form dual-layer ceramic membranes after sintering. Experiments demonstrated that membrane layers with almost the same properties were obtained despite the huge difference in support flux. When the support flux increases from 3.120 to 97.53 m3m?2h?1, the flux of these three membrane series have increased by 75%, 186% and 228%, respectively. Experimental rules can provide structural design and evaluation from the perspective of permeability. The limit membrane flux of a certain system was derived according to the resistance distribution law of internal membrane structure and the Darcy's theorem. On this basis, a method for designing support flux was proposed. Furthermore, we present a criterion to quickly and easily evaluate the match between the support and the top layer, which is the ratio of membrane resistance to total resistance. Finally, the filtration resistance of penetration caused by suction of membrane particles into the support was measured for the first time, taking the advantage of the transfer-coating method that inherently free of penetration. Our works are expected to deepen the understanding of the ceramic membrane structure and provided guidance for its rational design and optimization. 相似文献
35.
Tingen Zhu Wenping Li Qiqing Wang Yanbo Hu Kaifang Fan Jiafa Du 《Mine Water and the Environment》2020,39(1):57-67
A method to calculate the height of a water-conducting fractured zone (HWCFZ) was developed based on the plate and shell theory, and the development of the HWCFZ in bedrock and Q2l loess strata is discussed in detail. First, the subsidence-deflection curve equation of the overlying stratum is theoretically derived, and then the ultimate deflection and free space height of rock strata are calculated. Moreover, the strata tensile strain is calculated by using integral calculus. In addition, the failure state of the rock is analyzed by comparing the theoretically calculated tensile strain with the experimentally measured yield tensile strain, allowing one to attain the maximum value of HWCFZ. This approach was tested at the Jinjitan coal mine; the theoretically predicted, experimentally measured, and numerically computed maximum HWCFZ values were 189.5, 187.3, and 188.5 m, respectively, demonstrating the accuracy of the proposed method. These results are highly significant for safe and environment-friendly coal mining in northwest Shaanxi, China. 相似文献
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The red grape berry pigments, anthocyanins, were characterized in the early 20th century, but investigations of wine pigments were stymied during that era. The question of their identity was a major challenge for wine chemists. A number of techniques showed that the pigments were polymeric in nature. Some structures were postulated by mid-century based on reactions between anthocyanins and condensed tannin, and later postulated wine pigments were observed in model reactions. Some related compounds were then observed in wine. By the end of the 20th century, the ionization of non-volatiles for mass spectrometry opened the door to these compounds. In addition, a new class of compounds was observed, the pyranoanthocyanins, a product of fermentation and aging metabolites with anthocyanins. These compounds possess the pigment stability to SO2 and pH change that is characteristic of aged red wine. Aging experiments show a dynamic situation with shifts in the population of pigment classes over time. The very large number of diverse pigments explains why it has been so difficult to answer the century-old question of the structure of wine pigments. Our current understanding is founded on the use of mass spectral analysis using electrospray and related ionization techniques over the last 25 years. Future progress will rely on more sophisticated analysis of this very complex mixture of substances. © 2019 Society of Chemical Industry 相似文献
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CO2激光治疗皮肤基底细胞癌14例临床观察 总被引:4,自引:0,他引:4
目的 :探求一种简单 ,安全 ,效果好的基底细胞癌的治疗方法。方法 :对 1 4例基底细胞癌患者在局麻下用CO2 激光行基底细胞癌切除术或切除 +气化术。结果 :患者术中、术后出血少 ,伤口恢复快 ,愈合良好 ,疤痕表浅 ,随访未见复发。结论 :CO2 激光用于治疗基底细胞癌效果良好 ,无明显副作用 ,操作简单值得推广。 相似文献
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