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A Successive Shift Box-Counting Method for Calculating Fractal Dimensions and Its Application in Identification of Faults 被引量:1
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作者 沈晓华 邹乐君 +2 位作者 李宏升 沈忠悦 杨树峰 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2002年第2期257-263,共7页
Fractal dimensions of a terrain quantitatively describe the self-organizedstructure of the terrain geometry. However, the local topographic variation cannot be illustrated bythe conventional box-counting method. This ... Fractal dimensions of a terrain quantitatively describe the self-organizedstructure of the terrain geometry. However, the local topographic variation cannot be illustrated bythe conventional box-counting method. This paper proposes a successive shift box-counting method,in which the studied object is divided into small sub-objects that are composed of a series of gridsaccording to its characteristic scaling. The terrain fractal dimensions in the grids are calculatedwith the successive shift box-counting method and the scattered points with values of fractaldimensions are obtained. The present research shows that the planar variation of fractal dimensionsis well consistent with fault traces and geological boundaries. 展开更多
关键词 TERRAIN fractal dimension successive shift box-counting method identification of faults
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Improved Data Processing of Loading Spectrum for Applications of Rainflow Counting Method
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作者 吕志强 彭卫文 黄洪钟 《Journal of Donghua University(English Edition)》 EI CAS 2015年第6期919-922,共4页
The rainflow counting method is a reasonable cyclecounting procedure for fatigue life calculation and simulation testing of structures.It defines cycles as closed stress /strain hysteresis loops.Application of the rai... The rainflow counting method is a reasonable cyclecounting procedure for fatigue life calculation and simulation testing of structures.It defines cycles as closed stress /strain hysteresis loops.Application of the rainflow counting method requires a data processing of the loading spectrum,which consists of the elimination of non-peak value data points,load time histories adjustment and loop extraction.In the data processing of the loading spectrum,if a stress point is neither the peak nor the valley,it will be identified and eliminated from the loading spectrum.Generally,the loading process is idealized as a single peak-valley straight line.But in actually,there are polylines or nearly straight lines between peaks and valleys which can't be ignored.Therefore,in the process of eliminating such data points,it will produce error in method itself.To reduce the error produced by the traditional method itself,a new method which can well simplify the polylines in data processing of loading spectrum is proposed in this paper.Comparing with the original approximation method,the proposed method has higher precision. 展开更多
关键词 fatigue life rainflow counting method loading spectrum LOOP peaks and valleys
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The Study on Taxonomic Status of Trimeresurus stejnegeri chenbihuii Based on Scale Counting Method
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作者 Xiangjun WANG Wen CHEN +3 位作者 Haili TANG Yu DU Chixian LIN Wenjin CHEN 《Agricultural Biotechnology》 CAS 2020年第2期56-59,81,共5页
[Objectives] This study was conducted to further investigate the taxonomic status of Hainan population of Trimeresurus stejnegeri from the morphological point of view.[Methods]The difference coefficients between diffe... [Objectives] This study was conducted to further investigate the taxonomic status of Hainan population of Trimeresurus stejnegeri from the morphological point of view.[Methods]The difference coefficients between different populations were compared using the 75% law,and the relationship between scales and latitudes was analyzed.[Results] The scales(abdominal and subcaudal) of 325 Trimeresurus individuals were counted according to China Animal Fauna,including156 T.stejnegeri individuals.Some difference coefficients between the Hainan population and others were greater than 1.28,and there was no correlation between the number of scales and latitude.It conforms to subclassification criteria.[Conclusions]The view about the subspecies status of T.stejnegeri chenbihuii should be supported. 展开更多
关键词 TRIMERESURUS T.stejnegeri HAINAN SUBSPECIES Population SCALE counting method 75%law LATITUDE
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Research and application of uniform material counting method based on machine vision
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作者 XIAO Suhua QIAO Mingjuan +3 位作者 WANG Zhiyong WANG Wei FU Youzhi GUO Shusen 《Optoelectronics Letters》 EI 2023年第2期123-128,共6页
Manufacturing and agricultural industries use manual methods to count materials. This leads to low accuracy and inefficiency. This paper proposes a secondary counting method that combines main and differential countin... Manufacturing and agricultural industries use manual methods to count materials. This leads to low accuracy and inefficiency. This paper proposes a secondary counting method that combines main and differential counting. The area-fill identification algorithm is applied to mark the counted materials. To verify the effectiveness of the proposed counting algorithm, numbers of countings are conducted for different materials, such as the screws, hole gaskets, beans, jujube, etc. The results show that the counting accuracy reaches 98% for materials with size of 2—20 mm. The method has delivered a high-efficiency and high-accuracy automatic intelligent counting, with a wide range of application prospects and reference value. 展开更多
关键词 uniform material counting method machine vision
原文传递
ON THE LATTICE PATH METHOD IN CONVOLUTION-TYPE COMBINATORIAL IDENTITIES(Ⅱ)—THE WEIGHTED COUNTING FUNCTION METHOD ON LATTICE PATHS
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作者 初文吕 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1989年第12期1131-1135,共5页
An independent method for paper [10] is presented. Weighted lattice paths are enumerated by counting function which is a natural extension of Gaussian multinomial coefficient in the case of unrestricted paths. Convolu... An independent method for paper [10] is presented. Weighted lattice paths are enumerated by counting function which is a natural extension of Gaussian multinomial coefficient in the case of unrestricted paths. Convolutions for path counts are investigated, which yields some Vandcrmondc-type identities for multinomial and q-multinomial coefficients. 展开更多
关键词 THE WEIGHTED counting FUNCTION method ON LATTICE PATHS ON THE LATTICE PATH method IN CONVOLUTION-TYPE COMBINATORIAL IDENTITIES
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Fatigue Safety Assessment of Concrete Continuous Rigid Frame Bridge Based on Rain Flow Counting Method and Health Monitoring Data
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作者 Yinghua Li Junyong He +1 位作者 Xiaoqing Zeng Yanxing Tang 《Journal of Architectural Environment & Structural Engineering Research》 2023年第3期31-40,共10页
The fatigue of concrete structures will gradually appear after being subjected to alternating loads for a long time,and the accidents caused by fatigue failure of bridge structures also appear from time to time.Aiming... The fatigue of concrete structures will gradually appear after being subjected to alternating loads for a long time,and the accidents caused by fatigue failure of bridge structures also appear from time to time.Aiming at the problem of degradation of long-span continuous rigid frame bridges due to fatigue and environmental effects,this paper suggests a method to analyze the fatigue degradation mechanism of this type of bridge,which combines long-term in-site monitoring data collected by the health monitoring system(HMS)and fatigue theory.In the paper,the authors mainly carry out the research work in the following aspects:First of all,a long-span continuous rigid frame bridge installed with HMS is used as an example,and a large amount of health monitoring data have been acquired,which can provide efficient information for fatigue in terms of equivalent stress range and cumulative number of stress cycles;next,for calculating the cumulative fatigue damage of the bridge structure,fatigue stress spectrum got by rain flow counting method,S-N curves and damage criteria are used for fatigue damage analysis.Moreover,it was considered a linear accumulation damage through the Palmgren-Miner rule for the counting of stress cycles.The health monitoring data are adopted to obtain fatigue stress data and the rain flow counting method is used to count the amplitude varying fatigue stress.The proposed fatigue reliability approach in the paper can estimate the fatigue damage degree and its evolution law of bridge structures well,and also can help bridge engineers do the assessment of future service duration. 展开更多
关键词 Long-span continuous rigid frame bridge Rain flow counting method Fatigue performance Health monitoring system Strain monitoring data
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A Count Sketch Maximal Weighted Residual Kaczmarz Method with Oblique Projection for Highly Overdetermined Linear Systems 被引量:2
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作者 Peng Zhang Longyan Li Pingping Zhang 《Advances in Pure Mathematics》 2022年第4期260-270,共11页
Motivated by the count sketch maximal weighted residual Kaczmarz (CS-MWRK) method presented by Zhang and Li (Appl. Math. Comput., 410, 126486), we combine the count sketch tech with the maximal weighted residual Kaczm... Motivated by the count sketch maximal weighted residual Kaczmarz (CS-MWRK) method presented by Zhang and Li (Appl. Math. Comput., 410, 126486), we combine the count sketch tech with the maximal weighted residual Kaczmarz Method with Oblique Projection (MWRKO) constructed by Wang, Li, Bao and Liu (arXiv: 2106.13606) to develop a new method for solving highly overdetermined linear systems. The convergence rate of the new method is analyzed. Numerical results demonstrate that our method performs better in computing time compared with the CS-MWRK and MWRKO methods. 展开更多
关键词 count Sketch Oblique Projection Kaczmarz method Linear System
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Sensitivity of diagnosis of spontaneous bacterial peritonitis is higher with the automated cell count method 被引量:1
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作者 Juan G Acevedo-Haro Waddah Mohamed +8 位作者 Prebashan Moodley Oliver Bendall Kris Bennett Nigel Keelty Sally Chan Sam Waddy Joanne Hosking Wayne Thomas Robert Tilley 《World Journal of Hepatology》 2024年第11期1265-1281,共17页
BACKGROUND Spontaneous bacterial peritonitis(SBP)is one of the most important complications of patients with liver cirrhosis entailing high morbidity and mortality.Making an accurate early diagnosis of this infection ... BACKGROUND Spontaneous bacterial peritonitis(SBP)is one of the most important complications of patients with liver cirrhosis entailing high morbidity and mortality.Making an accurate early diagnosis of this infection is key in the outcome of these patients.The current definition of SBP is based on studies performed more than 40 years ago using a manual technique to count the number of polymorphs in ascitic fluid(AF).There is a lack of data comparing the traditional cell count method with a current automated cell counter.Moreover,current international guidelines do not mention the type of cell count method to be employed and around half of the centers still rely on the traditional manual method.AIM To compare the accuracy of polymorph count on AF to diagnose SBP between the traditional manual cell count method and a modern automated cell counter against SBP cases fulfilling gold standard criteria:Positive AF culture and signs/symptoms of peritonitis.METHODS Retrospective analysis including two cohorts:Cross-sectional(cohort 1)and case-control(cohort 2),of patients with decompensated cirrhosis and ascites.Both cell count methods were conducted simultaneously.Positive SBP cases had a pathogenic bacteria isolated on AF and signs/symptoms of peritonitis.RESULTS A total of 137 cases with 5 positive-SBP,and 85 cases with 33 positive-SBP were included in cohort 1 and 2,respectively.Positive-SBP cases had worse liver function in both cohorts.The automated method showed higher sensitivity than the manual cell count:80%vs 52%,P=0.02,in cohort 2.Both methods showed very good specificity(>95%).The best cutoff using the automated cell counter was polymorph≥0.2 cells×10^(9)/L(equivalent to 200 cells/mm^(3))in AF as it has the higher sensitivity keeping a good specificity.CONCLUSION The automated cell count method should be preferred over the manual method to diagnose SBP because of its higher sensitivity.SBP definition,using the automated method,as polymorph cell count≥0.2 cells×10^(9)/L in AF would need to be considered in patients admitted with decompensated cirrhosis. 展开更多
关键词 Spontaneous bacterial peritonitis DIAGNOSIS CIRRHOSIS Bacterial infection Automated cell count method Manual cell count method Ascitic fluid
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Comparative Study on the Correction of Lipemia Interference in Complete Blood Count
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作者 Lirong He 《Journal of Advances in Medicine Science》 2025年第1期1-5,共5页
Background:Lipemia,characterized by elevated triglyceride levels in blood samples,is a prevalent preanalytical interferent in clinical hematology.It leads to erroneous measurements of key complete blood count(CBC)para... Background:Lipemia,characterized by elevated triglyceride levels in blood samples,is a prevalent preanalytical interferent in clinical hematology.It leads to erroneous measurements of key complete blood count(CBC)parameters,including falsely elevated hemoglobin(Hgb)and platelet(PLT)counts.These inaccuracies can compromise diagnostic reliability and patient management.Objective:This review systematically evaluates existing correction methods for lipemic interference in CBC analysis,comparing their efficacy,limitations,and applicability in clinical settings.Methods:We analyze saline replacement,formula-based correction,instrument-specific algorithms,and emerging technologies,supported by experimental and clinical validation data.Conclusion:An optimized,context-dependent strategy is proposed,integrating multiple correction approaches based on lipemia severity.Future research directions,including artificial intelligence(AI)-enhanced corrections and standardized protocols,are discussed to advance hematology testing accuracy. 展开更多
关键词 Lipemic samples Hemoglobin interference Platelet counting Correction methods Hematology analyzers Optimization strategies
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Time-to-Count测量方法的应用研究 被引量:4
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作者 周伟 方方 +2 位作者 李扬红 李琳琳 黄洪全 《铀矿冶》 CAS 2009年第4期209-212,共4页
Time-to-Count方法是一种通过计算时间差来测量辐射强度的方法。通过控制加到探测元件上的高压,首先测量加上高压后到产生第一个脉冲计数之间的计数时间差,再根据计数时间差进一步计算出辐射强度。这种方法可以消除死时间、饱和电流和... Time-to-Count方法是一种通过计算时间差来测量辐射强度的方法。通过控制加到探测元件上的高压,首先测量加上高压后到产生第一个脉冲计数之间的计数时间差,再根据计数时间差进一步计算出辐射强度。这种方法可以消除死时间、饱和电流和高端脉冲重叠等因素的影响,提高探测效率。利用蒙特卡罗方法对Time-to-Count测量方法进行计算机模拟,进一步证明Time-to-Count测量方法的可行性。 展开更多
关键词 Time-to-count方法 计数时间差 辐射检测 蒙特卡罗模拟
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Time-to-Count方法扩展GM计数管量程的实验研究 被引量:9
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作者 龚军军 邵贝贝 +1 位作者 夏文明 陈君军 《原子能科学技术》 EI CAS CSCD 北大核心 2013年第4期674-678,共5页
GM计数管是一种应用广泛的核辐射探测器,但其线性量程范围较窄。本文分析了采用死时间模型和函数拟合修正方法扩展量程存在的不足,介绍了Time-to-Count方法的工作原理,给出了基于该方法的试验装置设计方案,对实现Time-to-Count方法的脉... GM计数管是一种应用广泛的核辐射探测器,但其线性量程范围较窄。本文分析了采用死时间模型和函数拟合修正方法扩展量程存在的不足,介绍了Time-to-Count方法的工作原理,给出了基于该方法的试验装置设计方案,对实现Time-to-Count方法的脉控高压驱动、时间间隔测量等进行了讨论。在国防科技工业电离辐射一级计量站的校准试验数据表明,试验装置采用单支G1220计数管,量程可扩展至5个数量级,全量程范围线性优于10%。 展开更多
关键词 量程扩展 Time-to-count方法 脉控高压驱动 时间间隔测量
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抽水蓄能电站钢蜗壳低周疲劳载荷谱编制方式研究
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作者 胡蕾 简敏 +2 位作者 张启灵 高晓峰 郭永成 《长江科学院院报》 北大核心 2026年第1期136-143,共8页
抽水蓄能电站机组在反复启停和变负荷运行状态下,钢蜗壳结构承受的静水压力会大幅度变化,长期作用下蜗壳可能发生低周疲劳破坏。以某抽水蓄能电站为例,在ABAQUS中完成了钢蜗壳结构的有限元仿真分析,再基于2016年全年水位监测数据编制不... 抽水蓄能电站机组在反复启停和变负荷运行状态下,钢蜗壳结构承受的静水压力会大幅度变化,长期作用下蜗壳可能发生低周疲劳破坏。以某抽水蓄能电站为例,在ABAQUS中完成了钢蜗壳结构的有限元仿真分析,再基于2016年全年水位监测数据编制不同时间长度的原型载荷谱,并在nCode Designlife平台利用雨流计数法对其处理计算,对比了原型载荷谱、处理后的载荷谱及几种极端情况下载荷谱计算得到的疲劳寿命。结果表明:(1)抽水蓄能电站充水保压蜗壳与混凝土间的间隙闭合存在一定的滞后性,与常规电站大直径充水保压蜗壳的间隙闭合规律相似,可能对抗疲劳性能不利。(2)低周疲劳载荷谱可采用雨流计数或常幅值简化编制方式,但对水位消落深度较大的电站,还需要进一步探索可靠的输入方式。(3)在电站运行期内,钢蜗壳无低周疲劳失效风险。研究结果可对钢蜗壳抗疲劳设计载荷的选取提供帮助。 展开更多
关键词 抽水蓄能电站 钢蜗壳结构 低周疲劳 载荷谱 雨流计数法
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基于直接计数法和动力学模型的横浪中破损船舶倾覆概率计算研究
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作者 段建文 马宁 史琪琪 《中国舰船研究》 北大核心 2026年第1期63-70,共8页
[目的]旨在基于直接计数法和动力学模型对横浪瘫船状态下破损船舶的倾覆概率进行计算分析,进而改进现行破损船舶稳性评估规范中,基于剩余稳性参数对倾覆概率进行保守估计的方法。[方法]根据所建动力学模型综合考虑波浪−船体−进舱水的耦... [目的]旨在基于直接计数法和动力学模型对横浪瘫船状态下破损船舶的倾覆概率进行计算分析,进而改进现行破损船舶稳性评估规范中,基于剩余稳性参数对倾覆概率进行保守估计的方法。[方法]根据所建动力学模型综合考虑波浪−船体−进舱水的耦合效应。对于波浪−船体耦合,采用瞬时湿表面压力积分方法计算非线性船体回复力和Froude−Krylov力;通过STF方法和脉冲响应函数法计算辐射力和绕射力;结合试验获得的破损船舶横摇阻尼,考虑流体黏性的影响。对于波浪−进舱水耦合效应,采用修正的伯努利方程,计算破口处的水体流入流出速率。对于船体−进舱水耦合,采用集中质量法计算进水晃荡力,同时通过瞬时湿表面压力积分方法考虑进水对船体的静压力。对于进水的黏性耗散作用,采用半经验公式进行近似计算。基于IMO规范和上述动力学模型,采用直接计数法计算破损船舶倾覆概率,并将其表示为时间的边际概率函数。[结果]将模型应用于破损船舶标准模型DTMB 5415,开展横摇运动响应和倾覆概率计算,主要结果如下:1)基于动力学模型计算得到的横摇运动响应结果,与试验结果对比显示,峰值对应周期附近的相对误差均在20%以内;2)该破损船模在30 min内的倾覆概率随有义波高的增大而升高,当波浪跨零周期接近船舶破损后的横摇固有周期时,倾覆概率达到最大值。[结论]研究表明,对于横浪中破损船舶倾覆概率,采用所提方法计算能够得到较为客观准确的结果。 展开更多
关键词 破损船舶 稳性 倾覆概率 动力学模型 直接计数法 边际概率函数 横浪 耦合效应
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流式细胞术定量检测后生元中灭活菌体的方法研究
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作者 李娇 李斌 +5 位作者 陈红贺 王徐萍 陈楠楠 路江浩 孟镇 刘明 《食品与发酵工业》 北大核心 2026年第4期361-367,共7页
该研究旨在建立一种利用流式细胞仪结合荧光染料SYTO 9与碘化丙啶(propidium iodide,PI)快速定量后生元样品中具有完整形态的灭活菌体数量的检测方法,以提升后生元产品质量控制技术。首先制备不同比例的益生菌活菌和灭活菌悬液进行流式... 该研究旨在建立一种利用流式细胞仪结合荧光染料SYTO 9与碘化丙啶(propidium iodide,PI)快速定量后生元样品中具有完整形态的灭活菌体数量的检测方法,以提升后生元产品质量控制技术。首先制备不同比例的益生菌活菌和灭活菌悬液进行流式检测,结果显示测定数据与添加比例基本一致,活菌和灭活菌线性回归系数分别为0.9979和0.9963。对益生菌活菌和灭活菌进行流式检测,并与平板计数法检测的活菌数比较,三者检测的菌体数基本一致(R^(2)=0.9955、0.9943、0.9902),验证了流式细胞术定量检测灭活菌体的可行性。将不同比例灭活菌悬液与后生元样品液混合后流式检测,检测比值与样品添加比例线性相关性良好(R^(2)=0.9951),验证了该方法定量检测后生元样品中灭活菌体的可行性。最后对8种后生元样品中的灭活菌体进行流式细胞术计数,检测值与商品标识值基本一致。该研究成功建立了一种针对后生元样品中具有完整菌体形态的灭活菌体的快速定量检测技术,对后生元产业健康发展具有重要意义。 展开更多
关键词 流式细胞术 后生元 灭活菌体 快速定量检测 平板计数法
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口罩过滤效率检测仪检测方法比较研究及分析
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作者 马子嘉 李腾 +3 位作者 孟盈 黄莎 简艳 石曙光 《计量与测试技术》 2026年第1期181-184,共4页
随着口罩需求的大幅度增长,其性能的检测成为重点。其中,颗粒物的过滤效率是检测的核心指标之一,目前在生产质检中的检测仪器主要采用光度计法和粒子计数器法。本文依据相关国家标准和行业标准,分析国内不同技术标准对检测条件的要求,... 随着口罩需求的大幅度增长,其性能的检测成为重点。其中,颗粒物的过滤效率是检测的核心指标之一,目前在生产质检中的检测仪器主要采用光度计法和粒子计数器法。本文依据相关国家标准和行业标准,分析国内不同技术标准对检测条件的要求,并根据扫描电迁移率粒径谱仪中过滤材料上下游气溶胶的粒径谱分布数据,对比两种方法对测定结果的影响,从而优化检测方法,为保障检测质量、更好地服务于医疗和个人防护提供技术支撑。 展开更多
关键词 口罩过滤效率 粒子计数法 光度计法 扫描电迁移率粒径谱仪
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循环水浴降温法对白细胞滤除效果和凝血因子Ⅷ质量的影响
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作者 康美艳 罗曼华 +1 位作者 刘福发 李津 《医疗装备》 2026年第1期1-3,7,共4页
目的探讨循环水浴降温法对白细胞滤除效果和凝血因子Ⅷ(FⅧ)质量的影响。方法选取2024年1月至2025年3月血站献血点正常采集的60袋400 ml全血(保存液为ACD-B,温度20~30℃),以随机数字表法分为对照组和试验组,每组30袋。对照组将全血袋平... 目的探讨循环水浴降温法对白细胞滤除效果和凝血因子Ⅷ(FⅧ)质量的影响。方法选取2024年1月至2025年3月血站献血点正常采集的60袋400 ml全血(保存液为ACD-B,温度20~30℃),以随机数字表法分为对照组和试验组,每组30袋。对照组将全血袋平铺放入2~6℃冰箱降温至2~6℃,试验组将全血袋放入2~6℃水浴箱循环水浴降温至2~6℃。比较两组降温用时、去白细胞全血的白细胞残留量、新鲜冰冻血浆的FⅧ含量及合格率。结果试验组降温用时短于对照组(P<0.05);两组去白细胞全血的白细胞残留量比较,差异无统计学意义(P>0.05);试验组新鲜冰冻血浆的FⅧ含量高于对照组(P<0.05);两组新鲜冰冻血浆FⅧ含量合格率比较,差异无统计学意义(P>0.05)。结论相比传统冰箱降温法,循环水浴降温法可缩短全血降温用时,提升新鲜冰冻血浆的FⅧ含量,且不影响去白细胞全血的白细胞残留量与新鲜冰冻血浆FⅧ含量合格率。 展开更多
关键词 循环水浴降温法 白细胞残留量 凝血因子Ⅷ含量
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一种复合季铵盐消毒剂对微生物实验室的消毒效果验证
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作者 周映佑 滕钰 +1 位作者 杨爽 薛咏兰 《中国消毒学杂志》 2026年第1期14-17,共4页
目的验证一种复合季铵盐消毒剂(有效成份含量)对微生物实验室的消毒效果。方法采用悬液定量杀菌试验和载体定量杀菌试验方法,对该复合季铵盐消毒剂的杀菌效果进行验证。结果该复合季铵盐消毒剂在微生物计数法中,采用含3%聚山梨酯80和0.3... 目的验证一种复合季铵盐消毒剂(有效成份含量)对微生物实验室的消毒效果。方法采用悬液定量杀菌试验和载体定量杀菌试验方法,对该复合季铵盐消毒剂的杀菌效果进行验证。结果该复合季铵盐消毒剂在微生物计数法中,采用含3%聚山梨酯80和0.3%卵磷脂的pH7.0无菌氯化钠–蛋白胨缓冲液作为稀释液,稀释级别为1:10,接种量为1 mL/皿时,5株标准菌的回收率均能达到0.5~2的要求。在消毒剂杀菌效果验证试验中,采用悬液法时,对金黄色葡萄球菌、铜绿假单胞菌和大肠埃希菌的杀灭对数值均>5.00,对白色念珠菌和黑曲霉的杀灭对数值均≥4.00,对环境微生物的杀灭对数值均≥3.00;采用载体定量杀菌试验法时,几种材质载体上标准菌株和环境微生物的杀灭对数值均≥3.00。结论该复合季铵盐消毒剂对标准菌株和环境微生物均具有较好的杀灭效果,可用于药品微生物实验室的消毒。 展开更多
关键词 复合季铵盐消毒剂 环境微生物 微生物计数法 杀灭对数值
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四象限铅栅模体法对SPECT固有空间分辨力和线性影响研究
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作者 洪浩 李静 +1 位作者 王雪鹃 耿建华 《中国医学装备》 2026年第1期28-33,共6页
目的:探索四象限铅栅方位、计数和源距的四象限铅栅模体法对单光子发射计算机断层成像(SPECT)固有空间分辨力和线性影响,为SPECT质量控制与性能检测方法提供参考。方法:依据国家卫生行业标准《伽玛照相机、单光子发射断层成像设备(SPECT... 目的:探索四象限铅栅方位、计数和源距的四象限铅栅模体法对单光子发射计算机断层成像(SPECT)固有空间分辨力和线性影响,为SPECT质量控制与性能检测方法提供参考。方法:依据国家卫生行业标准《伽玛照相机、单光子发射断层成像设备(SPECT)质量控制检测规范》(WS523-2019),将点源放置在距探头铅栅模体表面1.5、1.7、1.9、2.1和2.3 m(1.5~2.3 m),使用四象限铅栅模体法对北京协和医学院肿瘤医院在用的两台SPECT设备双探头所获取的图像固有空间分辨力和线性进行检测,每个点源位置分别采集安装四象限铅栅模体后的计数(60、100、200、300、500、600和1000 k),基于目测判断可分辨的四象限铅栅模体最小象限公式定量计算线源图像的半高宽及目测不同象限线性的畸变程度,检测获取两台SPECT设备双探头的固有空间分辨力和固有空间线性,并分析四象限铅栅不同方位图像可分辨最小象限和线性的一致性。结果:源距固定,当四象限铅栅模体采集计数依次为60 k、100 k、200~300 k、500~1000 k时,获取两台SPECT设备双探头四象限铅栅不同方位图像,四象限铅栅8个方位目测可分辨的最小象限即固有空间分辨力同时依次为4种情况,即四象限铅栅各象限不可分辨、第四象限(6.125 mm)、第三象限(5.25 mm)、第二象限(4.375 mm);固有空间线性均为不可分辨、无线性畸变。四象限铅栅模体检测图像采集计数固定,检测源距1.5~2.3 m时,两台SPECT设备双探头固有空间分辨力和线性检测结果相同。结论:四象限铅栅模体法可完成对SPECT设备固有空间分辨力和线性检测。检测源距在1.5~2.3 m内变化不会对检测结果产生影响。检测时应将每帧图像采集计数≥200 k,铅栅摆放方位优化为正面或反面4个位置。 展开更多
关键词 四象限铅栅法 方位 计数 源距 固有空间分辨力 固有空间线性
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一种快速检测环境中放射性物质的新方法
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作者 沈嘉钰 《粘接》 2026年第2期479-482,共4页
为提高水体中放射性物质的检测灵敏度,建立了一种基于电感耦合等离子体质谱法与液体闪烁计数法的镭-226的快速检测方法。结果表明,该方法镭-226的载体回收率平均为73.15%,检出限为0.02~0.05Bq/L,定量限为0.06~0.15 Bq/L,且回归方程R^(2)... 为提高水体中放射性物质的检测灵敏度,建立了一种基于电感耦合等离子体质谱法与液体闪烁计数法的镭-226的快速检测方法。结果表明,该方法镭-226的载体回收率平均为73.15%,检出限为0.02~0.05Bq/L,定量限为0.06~0.15 Bq/L,且回归方程R^(2)≥0.999 0,表明该方法具有较高的灵敏度和准确性;精密度均低于5%,平均为2.76%,表明该方法可重复性好;加标回收率为95.28%~98.75%,相对标准偏差为1.92%~3.15%;在实际样品检测中,镭-226的载体回收率为58.43%~84.26%,进一步验证了方法的适用性。本研究为水体中放射性物质的快速监测提供技术支撑,并为相关标准的制定奠定了科学基础。 展开更多
关键词 放射性物质 镭-226 冠醚树脂 电感耦合等离子体质谱法 液体闪烁计数法
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基于整车综合耐久试验的汽车座椅交变通用试验谱研究
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作者 施之瑄 邱宇 《汽车零部件》 2026年第1期77-82,共6页
针对汽车座椅耐久试验因“一车一谱”导致的研发成本高、周期长的问题,提出一种基于整车综合耐久试验的交变通用试验谱设计方法。通过采集紧凑型轿车、运动型多功能汽车(SUV)和多功能汽车(MPV)3种车型在多种工况下的座椅振动信号,采用... 针对汽车座椅耐久试验因“一车一谱”导致的研发成本高、周期长的问题,提出一种基于整车综合耐久试验的交变通用试验谱设计方法。通过采集紧凑型轿车、运动型多功能汽车(SUV)和多功能汽车(MPV)3种车型在多种工况下的座椅振动信号,采用雨流计数法进行载荷统计,结合S-N曲线与Miner线性累积损伤准则进行伪损伤计算,进而设计出5级交变通用试验谱。台架对比试验表明,交变通用试验谱与“一车一谱”的测试误差小于5%,试验时间节约约15%,能够有效覆盖不同车型的座椅耐久考核需求,表明该方法具备良好的工程适用性与经济性。 展开更多
关键词 汽车座椅 整车综合耐久试验 交变通用试验谱 雨流计数法 台架验证
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