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Detection of the End Point Temperature of Thermal Denatured Protein in Fish and Chicken Meat Through SDS-PAGE Electrophoresis 被引量:4
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作者 GAO Hongwei MAO Mao +2 位作者 LIANG Chengzhu LIN Chao XIANG Jianhai 《Journal of Ocean University of China》 SCIE CAS 2009年第1期95-99,共5页
Sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) was applied in the detection of the end point temperature (EPT) of thermal denatured protein in fish and meat in this study. It was also used in stu... Sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) was applied in the detection of the end point temperature (EPT) of thermal denatured protein in fish and meat in this study. It was also used in studying the thermal denatured temperature range of proteins in salmon and chicken meat. The results show that the temperature ranges of denatured proteins were from 65 ℃ to 75 ℃ , and these temperature ranges were influenced by the processing methods. Through SDS-PAGE, the features of repeated heating thermal denatured proteins under the same temperature and processing time were studied. The electrophoresis patterns of thermal denatured proteins determined through repeated heating at the same temperature did not exhibit any change. For the detection of cooked fish and meat samples, they were subjected to applying the SDS-PAGE method, which revealed an EPT ranging from 60 ℃ to 80 ℃ . 展开更多
关键词 end point temperature DETECTION SDS-PAGE electrophoresis
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Quark Number Susceptibility around the Chiral Critical End Point
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作者 蒋宇 侯丰尧 +1 位作者 罗翠柏 宗红石 《Chinese Physics Letters》 SCIE CAS CSCD 2015年第2期39-42,共4页
We calculate the quark number susceptibility (QNS) around the chiral critical end point (CEP). The CEP is found to be located at (μc,Tc)= (80 MeV, 148 MeV) where μc and Tc are the critical chemical potential... We calculate the quark number susceptibility (QNS) around the chiral critical end point (CEP). The CEP is found to be located at (μc,Tc)= (80 MeV, 148 MeV) where μc and Tc are the critical chemical potential and temperature, respectively. The QNS is found to have the highest and sharpest peak at the CEP. It is also found that, when the chemical potential μ is in the range of 60MeV≤ μ ≤ 110MeV, the QNS near the transition temperature is larger than the free field result, which indicates that the space-like damping mode dominates the degree of freedom of motion near the CEP. 展开更多
关键词 CEP QCD Quark Number Susceptibility around the Chiral Critical end point
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End points of clinical trials in metastatic castration-resistant prostate cancer:A systematic review
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作者 Giuseppe Colloca Antonella Venturino 《World Journal of Methodology》 2014年第2期123-132,共10页
AIM: To review the defnition and performance of the commonly used end points in trials of systemic thera-pies in metastatic castration-resistant prostate cancer patients. METHODS: A literature search was undertaken... AIM: To review the defnition and performance of the commonly used end points in trials of systemic thera-pies in metastatic castration-resistant prostate cancer patients. METHODS: A literature search was undertaken on PubMed database to identify studies meeting estab-lished criteria, with the aim of selecting randomized clinical trials and study definition and performance of their end points. The end points were grouped into three categories: overall survival (OS), time-to-event end points, and response end points. A special analysis was performed for secondary end points of the studies which documented a beneft in OS in the experimental arm. Finally, publishes analyses for surrogacy of the in-cluded end points were also reported. RESULTS: OS, time-to-event and response end points in 31 selected trials were analyzed. OS was the pri-mary end point in 14 trials, and the secondary end point in 17. A time-to-event end point was the primaryend point in 8 studies, and the secondary end point in 22; the most reported time-to-event end points were composite end points, and the events changed among trials. A response end point was the primary end point in 9 studies, in 3 it was prostate-specifc antigen (PSA)-related, in 3 pain-related and in 3 mixed. A response end point was the secondary end point in 19 studies: PSA response and radiologic response were the most frequently used secondary end points in 19 and 11 tri-als, respectively, while pain response was used in 5 studies.CONCLUSION: A homogeneous defnition of progres-sion in future trials is mandatory. Among response end points, pain-response and PSA-response appear to be the most reliable. 展开更多
关键词 METASTATIC CASTRATION-RESISTANT PROSTATE cancer end points Progression-free survival Prostate-specifc ANTIGEN Chemotherapy PALLIATIVE response
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Locating the QCD critical end point through peaked baryon number susceptibilities along the freeze-out line 被引量:1
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作者 李志镔 陈亦点 +1 位作者 李丹凝 黄梅 《Chinese Physics C》 SCIE CAS CSCD 2018年第1期32-37,共6页
We investigate the baryon number susceptibilities up to fourth order along different freeze-out lines in a holographic QCD model with a critical end point(CEP), and we propose that the peaked baryon number susceptib... We investigate the baryon number susceptibilities up to fourth order along different freeze-out lines in a holographic QCD model with a critical end point(CEP), and we propose that the peaked baryon number susceptibilities along the freeze-out line can be used as a clean signature to locate the CEP in the QCD phase diagram.On the temperature and baryon chemical potential plane, the cumulant ratio of the baryon number susceptibilities(up to fourth order) forms a ridge along the phase boundary, and develops a sword-shaped "mountain" standing upright around the CEP in a narrow and oblate region. The measurement of baryon number susceptibilities from heavy-ion collision experiments is along the freeze-out line. If the freeze-out line crosses the foot of the CEP mountain, then one can observe the peaked baryon number susceptibilities along the freeze-out line, and the kurtosis of the baryon number distributions has the highest magnitude. The data from the first phase of the beam energy scan program at the Relativistic Heavy Ion Collider indicates that there should be a peak of the kurtosis of the baryon number distribution at a collision energy of around 5 Ge V, which suggests that the freeze-out line crosses the foot of the CEP mountain and the summit of the CEP should be located nearby, around a collision energy of 3–7 GeV. 展开更多
关键词 QCD baryon number susceptibilities critical end point phase transition
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The entanglement properties of holographic QCD model with a critical end point
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作者 Zhibin Li Kun Xu Mei Huang 《Chinese Physics C》 SCIE CAS CSCD 2021年第1期175-186,共12页
We investigated different entanglement properties of a holographic QCD(hQCD)model with a critical end point at the finite baryon density.Firstly,we considered the holographic entanglement entropy(HEE)of this hQCD mode... We investigated different entanglement properties of a holographic QCD(hQCD)model with a critical end point at the finite baryon density.Firstly,we considered the holographic entanglement entropy(HEE)of this hQCD model in a spherical shaped region and a strip shaped region.It was determined that the HEE of this hQCD model in both regions can reflect QCD phase transition.Moreover,although the area formulas and minimal area equations of the two regions were quite different,the HEE exhibited a similar behavior on the QCD phase diagram.Therefore,we assert that the behavior of the HEE on the QCD phase diagram is independent of the shape of the subregions.However,the HEE is not an ideal parameter for the characterization of the entanglement between different subregions of a thermal system.As such,we investigated the mutual information(MI),conditional mutual information(CMI),and the entanglement of purification(Ep)in different strip shaped regions.We determined that the three entanglement quantities exhibited some universal behavior;their values did not change significantly in the hadronic matter phase but increased rapidly with the increase in T andμin the QGP phase.Near the phase boundary,these three entanglement quantities changed smoothly in the crossover region and continuously but not smoothly at CEP;they exhibited discontinuous behavior in the first phase transition region.These properties can be used to distinguish between the different phases of strongly coupled matter. 展开更多
关键词 holographic QCD critical end point entanglement properties
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A MAXIMUM PRINCIPLE FOR DISTRIBUTED PARAMETER SYSTEMS WITH MIXED PHASE-CONTROL CONSTRAINTS ANDENDPOINT CONSTRAINTS
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作者 张平健 《Acta Mathematica Scientia》 SCIE CSCD 1997年第2期151-158,共8页
This paper considered the optimal control problem for distributed parameter systems with mixed phase-control constraints and end-point constraints. Pontryagin's maximum principle for optimal control are derived vi... This paper considered the optimal control problem for distributed parameter systems with mixed phase-control constraints and end-point constraints. Pontryagin's maximum principle for optimal control are derived via Duboviskij-Milujin theorem. 展开更多
关键词 maximum principle distributed parameter systems end-point constraints Duboviskij-Milujin theorem additive vector measure
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Robust Speech Endpoint Detection in Airplane Cockpit Voice Background
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作者 Hongbing CHENG Ming LEI +1 位作者 Guorong HUANG Yan XIA 《Wireless Sensor Network》 2009年第5期489-495,共7页
A method of robust speech endpoint detection in airplane cockpit voice background is presented. Based on the analysis of background noise character, a complex Laplacian distribution model directly aiming at noisy spee... A method of robust speech endpoint detection in airplane cockpit voice background is presented. Based on the analysis of background noise character, a complex Laplacian distribution model directly aiming at noisy speech is established. Then the likelihood ratio test based on binary hypothesis test is carried out. The decision criterion of conventional maximum a posterior incorporating the inter-frame correlation leads to two separate thresholds. Speech endpoint detection decision is finally made depend on the previous frame and the observed spectrum, and the speech endpoint is searched based on the decision. Compared with the typical algorithms, the proposed method operates robust in the airplane cockpit voice background. 展开更多
关键词 Complex LAPLACIAN Model Maximum A POSTERIOR Criterion LIKELIHOOD Ratio Test Speech end- point Detection AIRPLANE COCKPIT VOICE
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恢刺肌肉起止点治疗脑卒中后上肢痉挛性瘫痪:随机对照试验
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作者 尚凯 李洪艳 +3 位作者 郭和东 攸泰然 郭航天 顿华帅 《中国针灸》 北大核心 2026年第1期9-15,共7页
目的:观察恢刺肌肉起止点治疗脑卒中后上肢痉挛性瘫痪的临床疗效。方法:将62例脑卒中后上肢痉挛性瘫痪患者随机分为观察组和对照组,每组31例。两组均予基础治疗,观察组予针刺健侧顶颞前斜线、百会、印堂、双侧风池,恢刺选取患侧上肢肱... 目的:观察恢刺肌肉起止点治疗脑卒中后上肢痉挛性瘫痪的临床疗效。方法:将62例脑卒中后上肢痉挛性瘫痪患者随机分为观察组和对照组,每组31例。两组均予基础治疗,观察组予针刺健侧顶颞前斜线、百会、印堂、双侧风池,恢刺选取患侧上肢肱二头肌起止点、尺侧腕屈肌起止点和桡侧腕屈肌起止点;对照组予常规针刺,穴取健侧顶颞前斜线、百会、印堂、水沟、双侧风池和患侧极泉、尺泽等。两组针刺均每日1次,每周5次,连续治疗4周。分别于治疗前后观察两组患者患侧上肢改良Ashworth痉挛评定量表(MAS)评级、Fugl-Meyer上肢运动功能评定(FMA-UE)评分和改良Barthel指数(MBI)评分,并于治疗后评定两组临床疗效。结果:治疗后,两组患者患侧上肢MAS评级均较治疗前降低(P<0.001,P<0.05),患侧FMA-UE、上肢MBI评分均较治疗前升高(P<0.001);观察组患者患侧FMA-UE、上肢MBI评分高于对照组(P<0.01)。观察组临床疗效优于对照组(P<0.05)。结论:恢刺肌肉起止点可有效改善脑卒中后上肢痉挛性瘫痪,降低肌张力,改善运动功能,提高生活质量。 展开更多
关键词 脑卒中 上肢痉挛性瘫痪 针刺 恢刺 肌肉起止点 随机对照试验
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英国职业技能评估有效性的制度建设与行动路径
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作者 王佳昕 《中国高教研究》 北大核心 2026年第2期75-82,共8页
“有证无能”是长期制约世界各国职业教育人才培养质量和职业资格证书公信力的核心痼疾,其背后折射出技能评估有效性不足的深层结构性矛盾。英国的现代学徒制作为职业教育与产业深度融合的典范之一,建立了“三级质量保证”评估管理体制... “有证无能”是长期制约世界各国职业教育人才培养质量和职业资格证书公信力的核心痼疾,其背后折射出技能评估有效性不足的深层结构性矛盾。英国的现代学徒制作为职业教育与产业深度融合的典范之一,建立了“三级质量保证”评估管理体制,并以终点评估计划为主要实施手段对学徒进行全方位职业技能评估,构建起一个以雇主信用背书为核心、以证据化治理为手段、以动态适配产业系统为追求的技能可信认证生态。基于此,在我国职业技能评估工作中,应构建“行业出题、多元答题”的评估信用体系、推行“基于证据链”的智能化技能评估范式和建立“数据驱动、持续迭代”的质量保证闭环系统。 展开更多
关键词 三级质量保证 技能评估有效性 终点评估计划
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基于激光雷达采集数据的车辆防碰撞预警研究
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作者 杨俊亭 李发国 张少华 《电子设计工程》 2026年第2期188-191,196,共5页
在电磁干扰和天气条件影响下,为实时更新车辆周围三维环境信息,提升驾驶员行驶的安全性,设计基于激光雷达采集数据的车辆防碰撞预警方法。采集车辆运行环境三维点云数据、目标车辆角度与距离点云数据;对三维点云数据进行聚类处理,得到... 在电磁干扰和天气条件影响下,为实时更新车辆周围三维环境信息,提升驾驶员行驶的安全性,设计基于激光雷达采集数据的车辆防碰撞预警方法。采集车辆运行环境三维点云数据、目标车辆角度与距离点云数据;对三维点云数据进行聚类处理,得到障碍物聚类簇;拟合聚类簇的边界特征,完成前车目标检测;对比分析前车点云数据以及角度与距离点云数据,保存吻合点云数据;建立前向安全距离模型,确定车辆行驶安全距离;当与前车距离小于安全距离时,发出警报,避免碰撞发生。实验证明,该方法可有效采集并聚类处理车辆运行环境三维点云数据,计算目标车辆1的运行速度在57~59 km/h之间,目标车辆2的运行速度在60~62 km/h之间,可确定安全距离。 展开更多
关键词 激光雷达 数据采集 车辆防碰撞 密度聚类算法 迭代终点拟合 安全距离模型
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Trends of Shoreline Position: An Approach to Future Prediction for Balasore Shoreline, Odisha, India
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作者 Nilay Kanti Barman Soumendu Chatterjee Ansar Khan 《Open Journal of Marine Science》 2015年第1期13-25,共13页
The present study aims to analyze the shift in shoreline due to coastal processes and formulate available for best estimate of future shoreline positions based on precedent shorelines. Information on rates and trends ... The present study aims to analyze the shift in shoreline due to coastal processes and formulate available for best estimate of future shoreline positions based on precedent shorelines. Information on rates and trends of shoreline change can be used to improve the understanding of the underlying causes and potential effects of coastal erosion which can support informed coastal management decisions. In this paper, researchers go over the changes in the recent positions of the shoreline of the Balasore coast for the 38 years from 1975 through 2013. The study area includes the Balasore coastal region from Rasalpur to Udaypur together with Chandipur, Choumukh, Chandrabali as well as Bichitrapur. Transects wise shoreline data base were developed for approximately 67 kilometers of shoreline and erosional/accretional scenario has also been analysed by delineating the shoreline from Landsat imageries of 1975, 1980, 1990, 1995, 2000, 2005, 2010 and 2013. A simple Linear Regression Model and End Point Rate (EPR) have been adopted to take out the rate of change of shoreline and its future positions, based on empirical observations at 67 transects along the Balasore coast. It is found that the north eastern part of Balasore coast in the vicinity of Subarnarekha estuary and Chandrabali beach undergo high rates of shore line shift. The shoreline data were integrated for long- (about 17 years) and short-term (about 7 years) shift rates analysis to comprehend the shoreline change and prediction. For the prediction of future shoreline, the model has been validated with the present shoreline position (2013). The rate of shoreline movement calculated from the fixed base line to shoreline position of 1975, 1980, 1990, 1995, 2000, 2005 and 2010 and based on this, the estimated shoreline of 2013 was calculated. The estimated shoreline was compared with the actual shoreline delineated from satellite imagery of 2013. The model error or positional shift at each sample point is observed. The positional error varies from??4.82 m to 212.41 m. It has been found that model prediction error is higher in the left hand side of river Subarnarekha. The overall error for the entire predicted shoreline was found to be 41.88 m by Root Mean Square Error (RMSE). In addition, it was tested by means difference between actual and predicted shoreline positions using “t” test and it has been found that predicted shore line is not significantly different from actual shoreline position at (t132 = 0.278) p < 0.01. 展开更多
关键词 Linear Regression Model end point Rate ROOT Mean SQUARE Error SHORELINE Change SHORELINE PREDICTION
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基于图像匹配的钢丝绳芯输送带接头抽动自动检测 被引量:1
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作者 李现国 郭宽宽 苗长云 《天津工业大学学报》 北大核心 2025年第2期78-83,共6页
针对钢丝绳芯输送带接头抽动检测有效性和准确性差的问题,提出一种基于图像匹配的钢丝绳芯输送带接头抽动自动检测方法。首先进行图像预处理,提高图像质量;然后使用自动阈值提取钢丝绳端头点;再利用改进的ORB算法进行图像匹配,将待检测... 针对钢丝绳芯输送带接头抽动检测有效性和准确性差的问题,提出一种基于图像匹配的钢丝绳芯输送带接头抽动自动检测方法。首先进行图像预处理,提高图像质量;然后使用自动阈值提取钢丝绳端头点;再利用改进的ORB算法进行图像匹配,将待检测图像和基准图像中的钢丝绳端头点一一对应;最后采用基于钢丝绳端头基准点集的接头抽动测量方法计算接头抽动量并进行故障定位。实验结果表明:本文方法能够自动检测并标识出钢丝绳芯输送带接头处的钢丝绳端头点,准确得到钢丝绳端头点的匹配点对,计算出单个钢丝绳端头抽动量、钢丝绳上(下)端头平均抽动量和接头整体抽动量,检测并标识出异常钢丝绳端头的位置和变化量,实现了对接头抽动的自动检测和综合判断。 展开更多
关键词 钢丝绳芯输送带 接头抽动 图像匹配 钢丝绳端头点提取 ORB算法
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Binary self-assembly of highly symmetric DNA nanocages via sticky-end engineering
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作者 Xiao-Rong Wu Chen-Wei Wu +4 位作者 Fei Ding Cheng Tian Wen Jiang Cheng-De Mao Chuan Zhang 《Chinese Chemical Letters》 SCIE CAS CSCD 2017年第4期851-856,共6页
Discrete and symmetric three-dimensional(3D) DNA nanocages have been revoked as excellent candidates for various applications,such as vip component encapsulation and organization(e.g.dye molecules,proteins,inorga... Discrete and symmetric three-dimensional(3D) DNA nanocages have been revoked as excellent candidates for various applications,such as vip component encapsulation and organization(e.g.dye molecules,proteins,inorganic nanoparticles,etc.) to construct new materials and devices.To date,a large variety of DNA nanocages has been synthesized through assembling small individual DNA motifs into predesigned structures in a bottom-up fashion.Most of them rely on the assembly using multiple copies of single type of motifs and a few sophisticated nanostructures have been engineered by co-assembling multi-types of DNA tiles simultaneously.However,the availability of complex DNA nanocages is still limited.Herein,we demonstrate that highly symmetric DNA nanocages consisted of binary DNA pointstar motifs can be easily assembled by deliberately engineering the sticky-end interaction between the component building blocks.As such,DNA nanocages with new geometries,including elongated tetrahedron(E-TET),rhombic dodecahedron(R-DOD),and rhombic triacontahedron(R-TRI) are successfully synthesized.Moreover,their design principle,assembly process,and structural features are revealed by polyacryalmide gel electrophoresis(PAGE),atomic force microscope(AFM) imaging,and cryogenic transmission electron microscope imaging(cryo-TEM) associated with single particle reconstruction. 展开更多
关键词 DNA nanotechnology Self-assembly Nanocage point-star motif Sticky-end
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基于1∶1型滴定分析中化学计量点是突跃范围中点的证明
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作者 季桂娟 许文辉 周屹博 《广州化工》 2025年第23期194-197,共4页
在滴定分析中需要讨论滴定突跃范围和终点误差。滴定突跃范围即滴定化学计量点(sp)前0.1%(-0.1%)到化学计量点后0.1%(+0.1%)的范围。终点误差是滴定终点(ep)和化学计量点不一致而产生的误差。利用林邦误差公式计算终点误差需要知道滴定... 在滴定分析中需要讨论滴定突跃范围和终点误差。滴定突跃范围即滴定化学计量点(sp)前0.1%(-0.1%)到化学计量点后0.1%(+0.1%)的范围。终点误差是滴定终点(ep)和化学计量点不一致而产生的误差。利用林邦误差公式计算终点误差需要知道滴定终点与化学计量点之间的范围。本文将证明1∶1型的四大滴定分析中化学计量点是滴定突跃范围中点,也就是滴定终点与化学计量点之间的范围是滴定突跃范围的二分之一。据此,当已知滴定突跃范围时,即可确定滴定终点与化学计量点之间的范围。 展开更多
关键词 滴定分析 滴定突跃范围 终点误差 化学计量点
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银氨离子配位数测定实验的思考与讨论
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作者 杨耀彬 王清华 +2 位作者 陈艳 王秀平 于子游 《吉林化工学院学报》 2025年第2期23-26,共4页
“银氨离子配位数的测定”是大学“无机化学实验”中的基础实验之一,此实验是以配位平衡和沉淀溶解平衡两大平衡原理为基础,主要通过滴定法实验操作和坐标法数据处理来完成的测定实验。实验构思巧妙,易操作,但在操作和数据处理过程中仍... “银氨离子配位数的测定”是大学“无机化学实验”中的基础实验之一,此实验是以配位平衡和沉淀溶解平衡两大平衡原理为基础,主要通过滴定法实验操作和坐标法数据处理来完成的测定实验。实验构思巧妙,易操作,但在操作和数据处理过程中仍存在一些值得思考的问题,如操作时滴定剂种类的选择、滴定终点的确定、实验过程中补水问题以及后期的数据处理问题等。针对以上问题进行思考、讨论,能使学生对实验的理解更加透彻,操作更加熟练,实验准确性更高。 展开更多
关键词 配位数测定 银氨离子 滴定剂 滴定终点 补水问题
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病毒感染性检测方法研究进展 被引量:2
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作者 叶永丽 李梓暄 +2 位作者 刘丽娟 孙秀兰 纪剑 《病毒学报》 北大核心 2025年第1期202-210,共9页
病毒感染性分析是病毒类生物医药、环境监测、食品安全监管等领域的重要内容,明确病毒感染性对于病毒污染水平与传播能力分析、污染预警、降低危害和损失至关重要。近年来,除传统的空斑形成单位法、终点稀释法和病灶形成单位测定法外,... 病毒感染性分析是病毒类生物医药、环境监测、食品安全监管等领域的重要内容,明确病毒感染性对于病毒污染水平与传播能力分析、污染预警、降低危害和损失至关重要。近年来,除传统的空斑形成单位法、终点稀释法和病灶形成单位测定法外,结合计算机和生物信息学等学科知识及技术开发了系列高性能的感染性病毒检测新方法,包括激光力细胞学法、细胞生物传感法、间接聚合酶链式反应(Polymerase chain reaction,PCR)法、无细胞荧光原位杂交法以及基于传统方法的改良技术等。这些新方法、新技术在缩短试验周期、提高检测灵敏度、准确度和特异性、可实现自动化等方面具有显著的优势。本文对病毒感染宿主细胞系的选择以及感染性病毒分析方法的原理、应用、性能等方面进行综述,以期为病毒污染防控特别是食源性病毒的监管策略制定提供参考依据。 展开更多
关键词 病毒 感染能力 空斑形成单位 终点稀释法 滴度
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酸种类及终点pH值对垃圾焚烧飞灰重金属浸出行为的影响 被引量:1
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作者 李锰 芦静 +8 位作者 孙英杰 王福浩 李卫华 张庆建 龙吉生 李寿辉 纪勇 王华伟 卞荣星 《中国无机分析化学》 北大核心 2025年第4期458-468,共11页
为探究垃圾焚烧飞灰酸洗脱毒工艺中酸添加及终点pH值控制对其重金属浸出行为的影响,采用具有浓度梯度的四种酸对飞灰进行酸洗处理,探究终点pH值对飞灰酸洗过程中重金属浸出行为及环境风险,以及飞灰残渣赋存重金属化学形态及矿物组成变... 为探究垃圾焚烧飞灰酸洗脱毒工艺中酸添加及终点pH值控制对其重金属浸出行为的影响,采用具有浓度梯度的四种酸对飞灰进行酸洗处理,探究终点pH值对飞灰酸洗过程中重金属浸出行为及环境风险,以及飞灰残渣赋存重金属化学形态及矿物组成变化的影响。结果表明:Pb、Cu和Cr的浸出量表现出醋酸>硝酸>硫酸>磷酸的趋势;Pb、Zn、Cu和Cr的浸出液pH值分别在9<pH<11、10<pH<11、pH≈11和6<pH<8时呈现最低浸出量;浸出重金属的综合环境风险(RI值)完全受Cd浸出液浓度的主导,且pH≈11时,浸出液RI值最小。总体上,磷酸酸洗环境下飞灰浸出液重金属环境风险最低,且酸洗飞灰残渣中各重金属赋存化学形态更为稳定;而醋酸酸洗环境下的浸出液重金属环境风险最高,主要是因为其对弱酸提取态重金属具体较高的浸出效率。研究结果可为飞灰的酸洗脱毒工艺比选及参数优化,以及酸洗液重金属环境风险管控等提供理论参考。 展开更多
关键词 垃圾焚烧飞灰 酸洗 终点pH值 重金属浸出 环境风险
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基于火焰特征提取和PSO-ELM算法的转炉碳温预测 被引量:1
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作者 张强 杨勇 +2 位作者 戴雨翔 赵博 林路 《钢铁研究学报》 北大核心 2025年第2期141-150,共10页
转炉炉口火焰的颜色和纹理与转炉碳含量及温度存在密切的联系,通过火焰特征提取和神经网络模型预测转炉碳温为转炉终点控制提供了新的思路。基于转炉炉口火焰光谱数据集以及PSO-ELM神经网络建立了转炉碳含量及温度预测模型。针对原始光... 转炉炉口火焰的颜色和纹理与转炉碳含量及温度存在密切的联系,通过火焰特征提取和神经网络模型预测转炉碳温为转炉终点控制提供了新的思路。基于转炉炉口火焰光谱数据集以及PSO-ELM神经网络建立了转炉碳含量及温度预测模型。针对原始光谱中含有较多的噪声、杂散光等问题,采用小波算法对光谱数据集进行降噪处理。由于炉口火焰光谱数据量大,冗余信息较多,采用Skowron差别矩阵的属性约简算法从给定的2048维波长数据中找到对决策结果具有显著影响的8个特征指标。通过计算8个特征指标的MIC系数,证明所选指标具有独立性与非共线性,避免了因为指标之间高度相关导致建模不稳定以及过拟合的风险。基于PSO-ELM算法建立了预测模型,针对ELM在初始化时随机产生输入权值和隐含层阈值的缺陷,采用粒子群算法进行了优化。通过将PSO-ELM模型应用到转炉碳温的预测中,实例验证表明该模型在碳温预测上的精度较高,预测效果良好,适用于转炉碳温预测,有较好的工程应用前景。 展开更多
关键词 转炉冶炼 终点控制 机理模型 炉口火焰识别 ELM神经网络
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代谢综合征对于社区2型糖尿病的影响研究 被引量:1
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作者 张宁 周育松 +2 位作者 胡洁 刘薇 袁申元 《中国医药指南》 2025年第1期116-118,共3页
目的评估北京市朝阳区垡头社区2型糖尿病(T2DM)标准化管理对血压、血糖、血脂控制的效果,探讨代谢综合征(MS)对社区T2DM患者终点事件的影响。方法纳入2012年8月至2012年10月北京市朝阳区垡头社区卫生服务中心北京社区糖尿病研究(BCDS)... 目的评估北京市朝阳区垡头社区2型糖尿病(T2DM)标准化管理对血压、血糖、血脂控制的效果,探讨代谢综合征(MS)对社区T2DM患者终点事件的影响。方法纳入2012年8月至2012年10月北京市朝阳区垡头社区卫生服务中心北京社区糖尿病研究(BCDS)项目中的201例T2DM患者,随访6年,期间31例失访,最终对170例进行分析。所有患者接受规范化管理,根据是否合并MS分为T2DM组(n=66)和T2DM+MS组(n=104),比较两组联合达标率,并分析终点事件。结果本中心T2DM+MS患病率为61.18%;两组联合达标率均有所提升但对比差异无统计学意义(均P>0.05)。共发生90例(52.94%)终点事件,T2DM+MS组冠心病、颈动脉狭窄和微血管病变主要终点事件的发生率高于T2DM组(均P<0.05)。结论MS的存在显著增加了社区T2DM患者的冠心病、颈动脉狭窄和微血管病变的风险。 展开更多
关键词 代谢综合征 2型糖尿病 社区管理 终点事件
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基于数据挖掘的电弧炉炼钢终点温度预测研究 被引量:1
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作者 胡航 邹雨池 +3 位作者 魏光升 李冠男 郭宇峰 杨凌志 《中南大学学报(自然科学版)》 北大核心 2025年第9期3627-3639,共13页
提出一种基于异常检测、特征选择和机器学习算法的电弧炉炼钢终点温度预测的数据挖掘策略,并通过包含31-1输入-输出对的1 235炉实际生产数据验证该策略的有效性。采用逻辑回归、k近邻、决策树、极端梯度增强这4种监督学习算法开发预测模... 提出一种基于异常检测、特征选择和机器学习算法的电弧炉炼钢终点温度预测的数据挖掘策略,并通过包含31-1输入-输出对的1 235炉实际生产数据验证该策略的有效性。采用逻辑回归、k近邻、决策树、极端梯度增强这4种监督学习算法开发预测模型,综合考察数据量、无监督学习异常检测算法、特征选择方法和监督学习建模算法对预测精度的影响。研究结果表明:极端梯度增强算法的预测效果优于其他3种,在±5、±10和±15℃的温度误差范围内,极端梯度增强算法的命中率分别超过40%、80%和95%;数据质量和数据量都会影响监督学习预测算法模型的预测效果,无监督学习算法自编码器能大幅度提高数据质量和预测精度,排列重要度特征选择可以简化模型结构,需要从数据、特征和算法等多个角度对预测问题进行全面分析。 展开更多
关键词 电弧炉炼钢 终点温度 预测模型 数据挖掘 机器学习 异常检测
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