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排序方式: 共有7323条查询结果,搜索用时 15 毫秒
1.
Junyu Chen Yuze Li Yuming Jiang Liucheng Mao Mi Lai Lixia Jiang Huihui Liu Zongxiu Nie 《Advanced functional materials》2021,31(52):2106743
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
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针对管道布局、最大允许能耗给定条件下快速热循环注塑成形(RHCM)注塑模具型腔表面快速均匀加热的问题,提出以单根加热棒热流密度为设计变量,以模具型腔表面升温效率和温度分布均匀性为目标,结合有限元模拟、响应面设计以及多目标粒子群优化技术来优化RHCM模具电加热系统。与优化前相比,加热系统优化后,模具型腔表面最大温差降低63.4%,加热系统总能耗降低9%。对比了不同注塑成形工艺条件下成形的平板塑件表面质量,结果表明,相对传统注塑成形(CIM)工艺,RHCM工艺将制品表面粗糙度Ra从320 nm降低到118 nm,并有效抑制了制品表面熔接痕、缩痕等缺陷;发现制品表面粗糙度与型腔表面对应点温度成负相关,说明优化后的型腔表面温度分布更有利于提升制品表面质量。 相似文献
4.
Ronen Gottesman Angang Song Igal Levine Maximilian Krause A. T. M. Nazmul Islam Daniel Abou‐Ras Thomas Dittrich Roel van de Krol Abdelkrim Chemseddine 《Advanced functional materials》2020,30(21)
A new method for enhancing the charge separation and photo‐electrochemical stability of CuBi2O4 photoelectrodes by sequentially depositing Bi2O3 and CuO layers on fluorine‐doped tin oxide substrates with pulsed laser deposition (PLD), followed by rapid thermal processing (RTP), resulting in phase‐pure, highly crystalline films after 10 min at 650 °C, is reported. Conventional furnace annealing of similar films for 72 h at 500 °C do not result in phase‐pure CuBi2O4. The combined PLD and RTP approach allow excellent control of the Bi:Cu stoichiometry and results in photoelectrodes with superior electronic properties compared to photoelectrodes fabricated through spray pyrolysis. The low photocurrents of the CuBi2O4 photocathodes fabricated through PLD/RTP in this study are primarily attributed to their low specific surface area, lack of CuO impurities, and limited, slow charge transport in the undoped films. Bare (without protection layers) CuBi2O4 photoelectrodes made with PLD/RTP shows a photocurrent decrease of only 26% after 5 h, which represents the highest stability reported to date for this material. The PLD/RTP fabrication approach offers new possibilities of fabricating complex metal oxides photoelectrodes with a high degree of crystallinity and good electronic properties at higher temperatures than the thermal stability of glass‐based transparent conductive substrates would allow. 相似文献
5.
Ismail Seçkin Çardaklı Ali Kalkanlı 《International Journal of Cast Metals Research》2019,32(3):145-153
In this study, as alternative methods to conventional production methods involving thin section copper permanent mould casting (fast solidification) and water atomization (rapid solidification) of AISI DC 53 cold work tool steel have been investigated. Thin slabs obtained by copper mould casting was homogenized at 1150 °C for one hour and then hot rolling was be applied. After hot rolling, conventional heat treatment have been applied to thin slabs. The same heat treatment procedure have been performed for a commercially available AISI DC 53 which is manufactured by thick section ingot casting and rolling. In order to investigate also the effect of rapid solidification on AISI DC 53 tool steel, steel powder was produced by water atomization technique. Experiments have revealed that thin steel slabs in permanent copper mould and rapidly solidified tool steel powder by water atomization have a more refined primary M7C3 carbides than commercially available steel. 相似文献
6.
Casein in fluid milk determines cheese yield and affects cheese quality. Traditional methods of measuring casein in milk involve lengthy sample preparations with labor-intensive nitrogen-based protein quantifications. The objective of this study was to quantify casein in fluid milk with different casein-to-crude-protein ratios using front-face fluorescence spectroscopy (FFFS) and chemometrics. We constructed calibration samples by mixing microfiltration and ultrafiltration retentate and permeate in different ratios to obtain different casein concentrations and casein-to-crude-protein ratios. We developed partial least squares regression and elastic net regression models for casein prediction in fluid milk using FFFS tryptophan emission spectra and reference casein contents. We used a set of 20 validation samples (including raw, skim, and ultrafiltered milk) to optimize and validate model performance. We externally tested another independent set of 20 test samples (including raw, skim, and ultrafiltered milk) by root mean square error of prediction (RMSEP), residual prediction deviation (RPD), and relative prediction error (RPE). The RMSEP for casein content quantification in raw, skim, and ultrafiltered milk ranged from 0.12 to 0.13%, and the RPD ranged from 3.2 to 3.4. The externally validated error of prediction was comparable to the existing rapid method and showed practical model performance for quality-control purposes. This FFFS-based method can be implemented as a routine quality-control tool in the dairy industry, providing rapid quantification of casein content in fluid milk intended for cheese manufacturing. 相似文献
7.
快循环同步加速器(RCS)是中国散裂中子源(CSNS)的重要组成部分。负氢粒子束经直线加速器加速至80 MeV,剥离成质子束注入至RCS环并加速累积至1.6 GeV引出打靶。束流通过安装在RCS环的壁电流探测器(WCM)感应得到束流的强度信息,环高频与环主二极磁铁的失配会导致束流的实际振荡偏离理论预测。本文通过对WCM的数据进行分析得到了纵向工作点、束流的实际振荡频率、束团的电荷量、束团的形状变化等信息,方便了加速器的调束,并对参数测量中的测量误差进行了分析。 相似文献
8.
随着煤矿开采强度的增大,采掘接替紧张问题已经成为限制煤炭产量进一步提升的障碍。要想缓解采掘接替紧张的情况,就要实现巷道的快速掘进。虽然煤巷的快速掘进问题已经解决,但是,岩巷的快速掘进是难点。简要阐述了目前常用的几种岩巷掘进技术,在此基础上分析了实现岩巷快速掘进的方法,以期为采矿掘进技术人员日后工作的顺利进行提供参考。 相似文献
9.
反应堆堆芯核设计涉及大量方案的搜索与详细计算,缩短方案搜索时间有利于提高核设计效率。数据挖掘技术通过对大量数据进行学习与模式识别,可实现核设计方案物理参数的快速预测,更快地筛选出可行的备选堆芯方案。本文基于数据挖掘的决策树4种算法:C4.5、RepTree、Random Forest及Random Tree,在计算时以燃料富集度、含可燃毒物燃料棒数量及含量作为自变量,以寿期内keff不均匀系数偏差(KUCD)、径向功率不均匀系数偏差(RPNCD)、径向中子通量不均匀系数偏差(RFNCD)、堆芯寿期(CL)作为目标函数,构成目标函数符合度(CPF),利用大量已知核设计参数的组件及堆芯设计方案作为数据挖掘训练集,构建数据挖掘模型,并用于对未知核设计参数的组件方案集合(测试集)进行CPF快速预测。结果表明,4种算法利用训练集构建数据挖掘模型的时间在0.6 s以内,各算法的交叉验证精度均在0.7以上,其中C4.5算法对CPF预测精度最高;对测试集方案的核设计参数预测中,单个方案的预测时间均在0.9 s以内,而Random Forest算法对CPF等于4的预测效果最好。 相似文献
10.
针对郴州某复杂硫化铅锌矿资源的性质特点,采用铅快速浮选后尾矿再磨再选的阶磨阶选工艺,较好地实现了铅锌的高效浮选回收。研究了磨矿方式、捕收剂和调整剂种类及用量等因素对该矿石浮选的影响,确定了最佳浮选条件,通过小型闭路浮选试验,得到了铅品位60.05%、回收率89.63%的铅精矿和锌品位47.01%、回收率88.14%的锌精矿。 相似文献