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51.
李林 《能源与节能》2021,(1):205-206,209
以井下防灭火中液态CO2应用为对象开展探究,在分析概述液态CO2防灭火技术的基础上,结合工程实际,对相关技术在煤矿井下生产中的具体应用做出分析探究,并对其应用效果进行总结.结果表明,该技术能够有效控制采空区火灾,对于提升矿井作业安全意义重大.  相似文献   
52.
基于在紫外光照下可变形的液晶高弹体与铁电驻极体材料,设计了一种光电转换器模型器件。该模型器件能实现在紫外光照射下的电信号输出功能。建立了光电耦合分析模型,并分析了紫外光光强对产生感应电荷的影响。结果表明,该模型器件可指导开发一种能够测量一定光强范围内紫外光强度的光电传感器。  相似文献   
53.
Using the interfacial jamming of cellulose nanocrystal (CNC) surfactants, a new concept, termed all‐liquid molding, is introduced to produce all‐liquid objects that retain the shape and details of the mold with high fidelity, yet remain all liquid and are responsive to external stimuli. This simple process, where the viscosity of the CNC dispersion can range from that of water to a crosslinked gel, opens tremendous opportunities for encapsulation, delivery systems, and unique microfluidic devices. The process described is generally applicable to any functionalized nanoparticles dispersed in one liquid and polymer ligands having complementary functionality dissolved in a second immiscible liquid. Such sculpted liquids retain all the characteristics of the liquids but retain shape indefinitely, very much like a solid, and provide a new platform for next‐generation soft materials.  相似文献   
54.
The goal of this study was application of corn starch and ground walnut shells in various amounts by weight as biofillers of natural rubber (NR) biocomposites. Additionally, ionic liquid 1-butyl-3-methylimidazolium chloride (BmiCl) and (3-aminopropyl)-triethoxysilane (APTES) were used to increase the activity of biofillers and to improve the curing characteristics of NR composites. The effect of biofillers used and their modification with aminosilane or ionic liquid on the curing characteristics of NR composites and their functional properties, including crosslink density, mechanical properties in static and dynamic conditions, hardness, thermal stability and resistance to thermo-oxidative aging were investigated. Starch and ground walnut shells were classified as inactive fillers, which can be used alternatively to commercial inactive fillers, e.g., chalk. BmiCl and APTES were successfully used to support the vulcanization and to improve the dispersion of biofillers in NR elastomer matrix. Vulcanizates with starch, especially those containing APTES and BmiCl, exhibited improved tensile properties due to the higher crosslink density and homogenous dispersion of starch, which resulted from BmiCl addition. NR filled with ground walnut shells demonstrated improved resistance to thermo-oxidative aging. It resulted from lignin present in walnut shells, the components of which belong to polyphenols, that have an antioxidant activity.  相似文献   
55.
56.
Endometrial cancer (EC) is the 4th most common neoplasm of the female genital tract, with 15–20% of patients being of high risk of recurrence which leads to a significant decrease in patient survival. Current therapeutic options for patients with EC are poor, being the combined therapy of carboplatin and paclitaxel the standard of care, with limited efficacy. Therefore, new therapeutic options and better monitoring tools are needed to improve the management of the disease. In the current case report, we showcase the value of liquid biopsy analyses in a microsatellite instability EC patient with initially good prognosis that however underwent rapid progression disease within 6 months post-surgery; through the study of plasma cfDNA/ctDNA dynamics to assess the tumour evolution during treatment, as well as the study of the uterine aspirate as a valuable sample that captures the intra-tumour heterogeneity that allows a comprehensive genomic profiling of the disease to identify potential therapeutic options. Furthermore, preclinical models were generated at the time of tumour progression to assess the efficacy of the identified targeted therapies.  相似文献   
57.
The field of single-cell analysis has advanced rapidly in the last decade and is providing new insights into the characterization of intercellular genetic heterogeneity and complexity, especially in human cancer. In this regard, analyzing single circulating tumor cells (CTCs) is becoming particularly attractive due to the easy access to CTCs from simple blood samples called “liquid biopsies”. Analysis of multiple single CTCs has the potential to allow the identification and characterization of cancer heterogeneity to guide best therapy and predict therapeutic response. However, single-CTC analysis is restricted by the low amounts of DNA in a single cell genome. Whole genome amplification (WGA) techniques have emerged as a key step, enabling single-cell downstream molecular analysis. Here, we provide an overview of recent advances in WGA and their applications in the genetic analysis of single CTCs, along with prospective views towards clinical applications. First, we focus on the technical challenges of isolating and recovering single CTCs and then explore different WGA methodologies and recent developments which have been utilized to amplify single cell genomes for further downstream analysis. Lastly, we list a portfolio of CTC studies which employ WGA and single-cell analysis for genetic heterogeneity and biomarker detection.  相似文献   
58.
在室温下,通过酸诱导液相沉积的方法,制备出了二氧化锗(GeO2)颗粒。制得的GeO2颗粒通过扫描电子显微镜(SEM),透射电子显微镜(TEM)和X射线衍射(XRD)进行表征。实验结果表明,向前驱液中加入酸,可以诱导锗酸根离子转化成立方体型的GeO2颗粒析出。而向反应液中再加入少量的聚乙烯吡咯烷酮(PVP)后,会析出纺锤体型的GeO2晶体颗粒。  相似文献   
59.
杨佳  刘保国 《电气技术》2008,(9):140-141
设计了一种新型电动油脂润滑泵的结构组成及工作原理,该泵采用微控制器自动控制润滑油脂定时定量输送至各润滑点,并配以液位开关实现低油位报警,大大减少了电机损耗,节省所需的油脂及电力,具有良好的应用前景.  相似文献   
60.
高放废液中^126Sn的放化分析   总被引:2,自引:1,他引:2  
以甲基异丁基酮(MIBK)萃取为主要步骤,放化分离高放废液中的~(126)Sn。全流程化学回收率约为60%。以SnO_2形式制成测量源,用HPGe γ谱仪测取γ谱图,由~(126)Sn的子体特征γ能峰面积,经化学回收率、探测效率校正后,计算得到高放废液中~(126)Sn的含量为371±29 Bq/ml。~(126)Sn的放射性活度约为高放废液总活度的4×10~(-7)。  相似文献   
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