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1.
Cancer remains an intractable medical problem. Rapid diagnosis and identification of cancer are critical to differentiate it from nonmalignant diseases. High-throughput biofluid metabolic analysis has potential for cancer diagnosis. Nevertheless, the present metabolite analysis method does not meet the demand for high-throughput screening of diseases. Herein, a high-throughput, cost-effective, and noninvasive urine metabolic profiling method based on TiO2/MXene-assisted laser desorption/ionization mass spectrometry (LDI-MS) is presented for the efficient screening of bladder cancer (BC) and nonmalignant urinary disease. Combined with machine learning, TiO2/MXene-assisted LDI-MS enables high diagnostic accuracy (96.8%) for the classification of patient groups (including 47 BC and 46 ureteral calculus (UC) patients) from healthy controls (113 cases). In addition, BC patients can also be identified from noncancerous UC individuals with an accuracy of 88.3% in the independent test cohort. Furthermore, metabolite variations between BC and UC individuals are investigated based on relative quantification, and related pathways are also discussed. These results suggest that this method, based on urine metabolic patterns, provides a potential tool for rapidly distinguishing urinary diseases and it may pave the way for precision medicine.  相似文献   
2.
对聚丙烯二装置丙烯球罐液位计不锈钢螺栓失效的原因进行了分析,结合锰铬不锈钢(200系列)的性能和国内市场上的现状,分析了锰铬不锈钢在化工生产中应用的风险,提出了应对方法。  相似文献   
3.
电流变材料及其结构设计   总被引:6,自引:1,他引:5  
对各种电流变材料做了较贩综述,并从结构与性能关系的角度进行了简单的分析,以鱼电流变材料的结构设计。  相似文献   
4.
改善晶粒分布的均匀性是获得高性能ZnO压敏陶瓷的重要手段之一.本文主要从平均晶粒尺寸、晶粒分布均匀性以及晶粒形状等角度研究了不同Sb2O3掺杂含量的ZnO压敏陶瓷试样,并应用晶粒尺寸分布不均匀系数ε和形状参数k对晶粒进行量化.结果表明:随着Sb2O3掺杂量的增加,试样的平均晶粒尺寸ε以及k呈现减小的趋势,晶粒尺寸分布均匀性改善,晶粒形状由细长向规整发展,这些结果也可以很好地解释试样电性能得到改善的原因.分析认为Sb2O3掺杂后形成的尖晶石相抑制了晶粒的异向生长,使得晶粒尺寸减小,晶粒分布均匀性以及晶粒形状得到改善,而且尖晶石相对大晶粒区晶粒生长的抑制作用比小晶粒区弱.  相似文献   
5.
温控防裂与横缝工作性态调控是混凝土拱坝施工期面临的两大难题,而冷却通水策略是控制拱坝混凝土安全、横缝开合的关键因素。为此,本文提出了混凝土拱坝温度应力与横缝性态智能控制方法,并综合应用智能化控制理念、仿真分析工具、自动控制技术构建了混凝土拱坝温度应力与横缝性态智能控制系统。分析表明,该系统有效调控了坝体应力与横缝工作性态、充分发挥了混凝土材料性能、大幅提升了温控施工效率,实现了拱坝温控防裂与横缝性态调控的多目标智能优化。  相似文献   
6.
Acrylonitrile–EPDM–styrene (AES) graft copolymers were synthesized by solution graft polymerization of styrene (St) and acrylonitrile (AN) onto EPDM in an n‐hexane/benzene solvent with benzoyl peroxide (BPO) as an initiator. The structure changes were studied by an FTIR spectrophotometer. The grafting parameters were calculated gravimetrically. The influence of the polymerization conditions, such as the reaction time, concentration of the initiator, EPDM content, and weight ratio of St/AN, on the structure of the products was investigated. It was found that a proper initiator concentration and EPDM content will give a high grafting ratio of the AES resin. The thermal property of the copolymer was studied using programmed thermogravimetric analysis (TGA). The results showed that the copolymer has a better heat‐resistant property than that of ABS, especially for the initial decomposition temperature (Tin) and the maximum weight loss rate temperature (Tmax). Also, the mechanism of the graft reaction was discussed. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 428–432, 2002  相似文献   
7.
电力负荷预测是电力系统规划的重要组成部分,也是电力系统经济运行的基础,其对电力系统规划和运行都极其重要。具有精确的预测方法可以保证能源的节约,避免资源的浪费。同时也可以缓解电能短缺所造成的重大影响。论文为了实现更好的电力负荷预测方法,研究了分形理论在电力负荷上的应用。将分形拼贴定理和分形插值法应用到电力负荷预测之中。提出了分形理论电力负荷预测模型,得到了分形插值预测模型。为了证明分形插值法的有效性,论文将分形预测模型与传统的BP神经网络电力负荷预测模型相比较。最后通过仿真算例说明了论文提出的分形插值预测模型预测精度更高,预测相对误差较小。并且分形理论可以很好地应用在电力系统负荷预测中,预测效果要好于BP神经网络预测模型。  相似文献   
8.
The effect of montmorillonite (Cloisite 6A) on the bulk polymerization of styrene initiated by benzoyl peroxide (BPO) was studied by the dilatometric determination of the polymerization rates. The bulk polymerization rates increased as the montmorillonite input quantity increased. The effect became greater when the BPO concentration decreased. Under the assumption that clay participated in the radical initiation reaction of the chains, the reaction orders for clay and BPO were determined to be approximately 1.0 and 0.5, respectively. X‐ray diffraction and thermogravimetric analysis studies showed that the structure and properties of the obtained polystyrene (PS)/montmorillonite nanocomposites were greatly affected by the BPO concentration. With lower BPO concentrations, a larger interlayer distance and a higher extent of delamination for the clay were observed in the obtained PS/montmorillonite nanocomposites. The nanocomposites prepared with lower BPO concentrations also showed higher heat‐decomposition‐resistance temperatures. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 96: 1146–1152, 2005  相似文献   
9.
A series of polyacrylate-graft-poly (vinyl chloride) (ACR-g-PVC) resins were prepared through suspension graft copolymerization. Three kinds of polyacrylate latices were grafted by vinyl chloride using suspension polymerization method at 57 ± 0.1°C, respectively. The dynamic mechanical and rheological properties and the morphology of the resulting ACR-g-PVC resins were investigated. Poly (butyl acrylate)-graft-poly (vinyl chloride) (PBA-g-PVC) resin exhibited better toughness, and the optimized content of PBA in ACR-g-PVC resin was 6–8 wt%. The melt viscosity of ACR-g-PVC resin was much lower than that of pure PVC. The nature of the fracture surfaces of ACR-g-PVC material indicated that it has good toughness. The impact strength of the PBA-g-PVC material was greatly improved compared with that of pure PVC. The Young's modulus of the ACR-g-PVC material containing less than 15 wt% of PBA was comparable to that of pure PVC according to their dynamic mechanical analysis curves. For all of the ACR-g-PVC resins, there were two individual relaxations in the low-temperature range. One was β transition of PVC, and the other was α transition of ACR. The glass transition temperature of PVC in the ACR-g-PVC resin shifted to lower temperature when the content of the PBA was above 50 wt%. POLYM. ENG. SCI., 47:996–1003, 2007. © 2007 Society of Plastics Engineers  相似文献   
10.
碘化钾水溶液中碘在活性炭上的吸附等温线   总被引:1,自引:0,他引:1  
测定了碘化钾水溶液中碘在活性炭上的吸附平衡数据,证明碘在液固两相中的平衡关系可用Freundlich方程式拟合,其平衡方程式为:x/m=0.381C  相似文献   
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