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Preliminary study on a quantification method and standardization for aquatic microbial loads based on microbial diversity absolute quantitative sequencing
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作者 Wen Li Jing Libin +4 位作者 Li Xiawei Lu Jing Jin Haowei Yang Yongqi Li Xueling 《China Standardization》 2026年第1期68-73,共6页
This study establishes and validates a method for the precise quantification of aquatic microbial loads using microbial diversity absolute quantitative sequencing.By adding synthetic spike-in DNA to water samples from... This study establishes and validates a method for the precise quantification of aquatic microbial loads using microbial diversity absolute quantitative sequencing.By adding synthetic spike-in DNA to water samples from the Dahei River prior to DNA extraction and 16S rRNA gene sequencing,it generates standard curves to convert sequencing data into absolute microbial copy numbers.The method,which is proved highly accurate(R^(2)>0.99),reveals a clear contrast between the river sites:the upstream community has not only a significantly higher total microbial load but also a completely different makeup of species compared to the downstream site.This approach effectively overcomes the limitations of relative abundance analysis,providing a powerful tool for environmental monitoring,and proposes key steps for future standardization to ensure data comparability and integration. 展开更多
关键词 absolute quantification microbial load 16S rRNA sequencing spike-in STANDARDIZATION aquatic microbes
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Sequential search-based Latin hypercube sampling scheme for digital twin uncertainty quantification with application in EHA 被引量:1
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作者 Dong LIU Shaoping WANG +1 位作者 Jian SHI Di LIU 《Chinese Journal of Aeronautics》 2025年第4期176-192,共17页
For uncertainty quantification of complex models with high-dimensional,nonlinear,multi-component coupling like digital twins,traditional statistical sampling methods,such as random sampling and Latin hypercube samplin... For uncertainty quantification of complex models with high-dimensional,nonlinear,multi-component coupling like digital twins,traditional statistical sampling methods,such as random sampling and Latin hypercube sampling,require a large number of samples,which entails huge computational costs.Therefore,how to construct a small-size sample space has been a hot issue of interest for researchers.To this end,this paper proposes a sequential search-based Latin hypercube sampling scheme to generate efficient and accurate samples for uncertainty quantification.First,the sampling range of the samples is formed by carving the polymorphic uncertainty based on theoretical analysis.Then,the optimal Latin hypercube design is selected using the Latin hypercube sampling method combined with the"space filling"criterion.Finally,the sample selection function is established,and the next most informative sample is optimally selected to obtain the sequential test sample.Compared with the classical sampling method,the generated samples can retain more information on the basis of sparsity.A series of numerical experiments are conducted to demonstrate the superiority of the proposed sequential search-based Latin hypercube sampling scheme,which is a way to provide reliable uncertainty quantification results with small sample sizes. 展开更多
关键词 Digital Twin(DT) Genetic algorithms(GA) Optimal Latin Hypercube Design(Opt LHD) Sequential test Uncertainty quantification(UQ) EHA
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A Gel-Free Budget-Friendly Approach to GFP-Tagged Viruses Quantification in Plant Samples
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作者 Rohith Grandhi Mélodie B.Plourde +1 位作者 Aditi Balasubramani Hugo Germain 《Phyton-International Journal of Experimental Botany》 2025年第5期1497-1504,共8页
Viral diseases are an important threat to crop yield,as they are responsible for losses greater than US$30 billion annually.Thus,understanding the dynamics of virus propagation within plant cells is essential for devi... Viral diseases are an important threat to crop yield,as they are responsible for losses greater than US$30 billion annually.Thus,understanding the dynamics of virus propagation within plant cells is essential for devising effective control strategies.However,viruses are complex to propagate and quantify.Existing methodologies for viral quantification tend to be expensive and time-consuming.Here,we present a rapid cost-effective approach to quantify viral propagation using an engineered virus expressing a fluorescent reporter.Using a microplate reader,we measured viral protein levels and we validated our findings through comparison by western blot analysis of viral coat protein,the most common approach to quantify viral titer.Our proposed methodology provides a practical and accessible approach to studying virus-host interactions and could contribute to enhancing our understanding of plant virology. 展开更多
关键词 Microplate reader CP-PlAMV viruses plant viral quantification green fluorescent protein western blot quantification Nicotiana benthamiana Arabidopsis thaliana Pearson’s correlation
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Quantification of Streptococcus salivarius using the digital polymerase chain reaction as a liver fibrosis marker
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作者 Shuichiro Iwasaki Akira Také +8 位作者 Haruki Uojima Kazue Horio Yoshihiko Sakaguchi Kazuyoshi Gotoh Takashi Satoh Hisashi Hidaka Yasuhito Tanaka Shunji Hayashi Chika Kusano 《World Journal of Hepatology》 2025年第4期53-66,共14页
BACKGROUND The Streptococcus salivarius(S.salivarius)group,which produces the enzyme urease has been identified as a potential contributor to ammonia production in the gut.Researchers have reported that patients with ... BACKGROUND The Streptococcus salivarius(S.salivarius)group,which produces the enzyme urease has been identified as a potential contributor to ammonia production in the gut.Researchers have reported that patients with minimal HE had an increased abundance of the S.salivarius group,which is a specific change in the gut microbiota that distinguishes them from healthy individuals.The correlation between the aggregation of specific bacterial species and fibrosis progression in chronic liver disease(CLD)is yet to be fully elucidated.AIM To quantify S.salivarius using digital PCR(dPCR)as a liver fibrosis marker of CLD.METHODS This study retrospectively analysed 52 patients with CLD.To quantify S.salivarius in patients with CLD using dPCR,we evaluated the specificity and sensitivity of S.salivarius bacterial load using dPCR for a type strain.Next,we evaluated the clinical usefulness of dPCR for S.salivarius load quantification for detecting liver fibrosis in patients with CLD.The liver fibrosis stage was categorized into mild and advanced fibrosis based on pathological findings.RESULTS The dPCR assay revealed that S.salivarius was highly positive for the tnpA gene.The lower limit of quantification for dPCR using the tnpA gene with a 1μL template comprising 1.28×102 CFU/mL was 4.3 copies.After considering the detection range in dPCR,we adjusted the extracted DNA concentration to 5.0×10-4 ng/μL from 200 mg stool samples.The median bacterial loads of S.salivarius in stool sample from patients with mild and advanced fibrosis were 1.9 and 7.4 copies/μL,respectively.The quantification of S.salivarius load was observed more frequently in patients with advanced fibrosis than in those with mild fibrosis(P=0.032).CONCLUSION Quantifying of S.salivarius load using digital PCR is a useful biomarker for liver fibrosis in patients with CLD. 展开更多
关键词 Chronic liver disease Streptococcus salivarius Digital PCR Liver fibrosis Liver cirrhosis quantification
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Fe^(3+) ion quantification with reusable bioinspired nanopores
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作者 Yanqiong Wang Yaqi Hou +1 位作者 Fengwei Huo Xu Hou 《Chinese Chemical Letters》 2025年第2期179-184,共6页
Excessive Fe^(3+) ion concentrations in wastewater pose a long-standing threat to human health.Achieving low-cost,high-efficiency quantification of Fe^(3+) ion concentration in unknown solutions can guide environmenta... Excessive Fe^(3+) ion concentrations in wastewater pose a long-standing threat to human health.Achieving low-cost,high-efficiency quantification of Fe^(3+) ion concentration in unknown solutions can guide environmental management decisions and optimize water treatment processes.In this study,by leveraging the rapid,real-time detection capabilities of nanopores and the specific chemical binding affinity of tannic acid to Fe^(3+),a linear relationship between the ion current and Fe^(3+) ion concentration was established.Utilizing this linear relationship,quantification of Fe^(3+) ion concentration in unknown solutions was achieved.Furthermore,ethylenediaminetetraacetic acid disodium salt was employed to displace Fe^(3+) from the nanopores,allowing them to be restored to their initial conditions and reused for Fe^(3+) ion quantification.The reusable bioinspired nanopores remain functional over 330 days of storage.This recycling capability and the long-term stability of the nanopores contribute to a significant reduction in costs.This study provides a strategy for the quantification of unknown Fe^(3+) concentration using nanopores,with potential applications in environmental assessment,health monitoring,and so forth. 展开更多
关键词 Bioinspired nanopores Fe^(3+)ion quantification Chemical binding affinity Tannic acid REUSABILITY
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Uncertainty Quantification of Dynamic Stall Aerodynamics for Large Mach Number Flow around Pitching Airfoils
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作者 Yizhe Han Guangjing Huang +2 位作者 Fei Xiao Zhiyin Huang Yuting Dai 《Fluid Dynamics & Materials Processing》 2025年第7期1657-1671,共15页
During high-speed forward flight,helicopter rotor blades operate across a wide range of Reynolds and Mach numbers.Under such conditions,their aerodynamic performance is significantly influenced by dynamic stall—a com... During high-speed forward flight,helicopter rotor blades operate across a wide range of Reynolds and Mach numbers.Under such conditions,their aerodynamic performance is significantly influenced by dynamic stall—a complex,unsteady flow phenomenon highly sensitive to inlet conditions such asMach and Reynolds numbers.The key features of three-dimensional blade stall can be effectively represented by the dynamic stall behavior of a pitching airfoil.In this study,we conduct an uncertainty quantification analysis of dynamic stall aerodynamics in high-Mach-number flows over pitching airfoils,accounting for uncertainties in inlet parameters.A computational fluid dynamics(CFD)model based on the compressible unsteady Reynolds-averagedNavier–Stokes(URANS)equations,coupledwith sliding mesh techniques,is developed to simulate the unsteady aerodynamic behavior and associated flow fields.To efficiently capture the aerodynamic responses while maintaining high accuracy,a multi-fidelity Co-Kriging surrogate model is constructed.This model integrates the precision of high-fidelity wind tunnel experiments with the computational efficiency of lower-fidelity URANS simulations.Its accuracy is validated through direct comparison with experimental data.Building upon this surrogate model,we employ interval analysis and the Sobol sensitivity method to quantify the uncertainty and parameter sensitivity of the unsteady aerodynamic forces resulting frominlet condition variability.Both the inlet Mach number and Reynolds number are treated as uncertain inputs,modeled using interval representations.Our results demonstrate that variations inMach number contribute far more significantly to aerodynamic uncertainty than those in Reynolds number.Moreover,the presence of dynamic stall vortices markedly amplifies the aerodynamic sensitivity to Mach number fluctuations. 展开更多
关键词 Dynamic stall uncertainty quantification multi-fidelity surrogate modeling sensitivity analysis
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Research on Quantification Mechanism of Data Source Reliability Based on Trust Evaluation
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作者 Gaoshang Lu Fa Fu Zixiang Tang 《Computers, Materials & Continua》 2025年第6期4239-4256,共18页
In the data transaction process within a data asset trading platform,quantifying the trustworthiness of data source nodes is challenging due to their numerous attributes and complex structures.To address this issue,a ... In the data transaction process within a data asset trading platform,quantifying the trustworthiness of data source nodes is challenging due to their numerous attributes and complex structures.To address this issue,a distributed data source trust assessment management framework,a trust quantification model,and a dynamic adjustment mechanism are proposed.Themodel integrates the Analytic Hierarchy Process(AHP)and Dempster-Shafer(D-S)evidence theory to determine attribute weights and calculate direct trust values,while the PageRank algorithm is employed to derive indirect trust values.Thedirect and indirect trust values are then combined to compute the comprehensive trust value of the data source.Furthermore,a dynamic adjustment mechanism is introduced to continuously update the comprehensive trust value based on historical assessment data.By leveraging the collaborative efforts of multiple nodes in the distributed network,the proposed framework enables a comprehensive,dynamic,and objective evaluation of data source trustworthiness.Extensive experimental analyses demonstrate that the trust quantification model effectively handles large-scale data source trust assessments,exhibiting both strong trust differentiation capability and high robustness. 展开更多
关键词 Trust evaluation data source reliability distributed network quantification mechanism
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MultiJSQ:Direct joint segmentation and quantification of left ventricle with deep multitask-derived regression network
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作者 Xiuquan Du Zheng Pei +3 位作者 Ying Liu Xinzhi Cao Lei Li Shuo Li 《CAAI Transactions on Intelligence Technology》 2025年第1期175-192,共18页
Quantitative analysis of clinical function parameters from MRI images is crucial for diagnosing and assessing cardiovascular disease.However,the manual calculation of these parameters is challenging due to the high va... Quantitative analysis of clinical function parameters from MRI images is crucial for diagnosing and assessing cardiovascular disease.However,the manual calculation of these parameters is challenging due to the high variability among patients and the time-consuming nature of the process.In this study,the authors introduce a framework named MultiJSQ,comprising the feature presentation network(FRN)and the indicator prediction network(IEN),which is designed for simultaneous joint segmentation and quantification.The FRN is tailored for representing global image features,facilitating the direct acquisition of left ventricle(LV)contour images through pixel classification.Additionally,the IEN incorporates specifically designed modules to extract relevant clinical indices.The authors’method considers the interdependence of different tasks,demonstrating the validity of these relationships and yielding favourable results.Through extensive experiments on cardiac MR images from 145 patients,MultiJSQ achieves impressive outcomes,with low mean absolute errors of 124 mm^(2),1.72 mm,and 1.21 mm for areas,dimensions,and regional wall thicknesses,respectively,along with a Dice metric score of 0.908.The experimental findings underscore the excellent performance of our framework in LV segmentation and quantification,highlighting its promising clinical application prospects. 展开更多
关键词 global image features joint segmentation and quantification left ventricle(LV) multitask-derived regression network
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Quantification and reduction of uncertainty in aerodynamic performance of GAN-generated airfoil shapes using MC dropouts
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作者 Kazuo Yonekura Ryuto Aoki Katsuyuki Suzuki 《Theoretical & Applied Mechanics Letters》 2025年第4期372-377,共6页
Generative adversarial network(GAN)models are widely used in mechanical designs.The aim in the airfoil shape design is to obtain shapes that exhibits the required aerodynamic performance,and conditional GAN is used fo... Generative adversarial network(GAN)models are widely used in mechanical designs.The aim in the airfoil shape design is to obtain shapes that exhibits the required aerodynamic performance,and conditional GAN is used for that aim.However,the output of GAN contains uncertainties.Additionally,the uncertainties of labels have not been quantified.This paper proposes an uncertainty quantification method to estimate the uncertainty of labels using Monte Carlo dropout.In addition,an uncertainty reduction method is proposed based on imbalanced training.The proposed method was evaluated for the airfoil generation task.The results indicated that the uncertainty was appropriately quantified and successfully reduced. 展开更多
关键词 Uncertainty quantification GAN Airfoil shapegeneration
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A rapid tool for quantification of latent infection of wheat leaves by powdery mildew
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作者 Aolin Wang Ru Jiang +9 位作者 Meihui Zhang Hudie Shao Fei Xu Kouhan Liu Haifeng Gao Jieru Fan Wei Liu Xiaoping Hu Yilin Zhou Xiangming Xu 《Journal of Integrative Agriculture》 2025年第12期4690-4702,共13页
Wheat powdery mildew caused by Blumeria graminis f.sp.tritici(Bgt)is an important disease worldwide.Detection of latent infection of leaves by the pathogen in late autumn is valuable for estimating the inoculum potent... Wheat powdery mildew caused by Blumeria graminis f.sp.tritici(Bgt)is an important disease worldwide.Detection of latent infection of leaves by the pathogen in late autumn is valuable for estimating the inoculum potential to assess disease risks in the spring.We developed a new tool for rapid detection and quantification of latent infection of seedlings by the pathogen.The method was based on recombinase polymerase amplification(RPA)coupled with an end-point detection via lateral flow device(LFD).The limit of detection is 100 agμL^(-1)of Bgt DNA,without noticeable interference from either other common wheat pathogens or wheat material(Triticum aestivum).It was evaluated on wheat seedlings for this accuracy and sensitivity in detecting latent infection of Bgt.We further extended this RPALFD assay to estimate the level of latent infection by Bgt based on imaging analysis.There was a strong correlation between the image-based and real-time PCR assay estimates of Bgt DNA.The present results suggested that this new tool can provide rapid and accurate quantification of Bgt in latently infected leaves and can be further development as an on-site monitoring tool. 展开更多
关键词 Blumeria graminis f.sp.tritici(Bgt) recombinase polymerase amplification(RPA) lateral flow device(LFD) image-based quantification disease monitoring
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骨骼肌脂肪浸润的评估方法:定量磁共振成像
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作者 王静 李军飞 赵建 《磁共振成像》 北大核心 2026年第1期201-207,共7页
骨骼肌脂肪浸润(fat infiltration,FI)广泛参与多种疾病的病理发展进程,准确评估肌肉FI的程度对于制定有效的治疗方案及干预疾病进展具有至关重要的意义。放射学参数量化FI,特别是基于定量磁共振成像(quantitative magnetic resonance i... 骨骼肌脂肪浸润(fat infiltration,FI)广泛参与多种疾病的病理发展进程,准确评估肌肉FI的程度对于制定有效的治疗方案及干预疾病进展具有至关重要的意义。放射学参数量化FI,特别是基于定量磁共振成像(quantitative magnetic resonance imaging,qMRI)技术的衍生参数,已经展现出作为疾病诊断要素和代谢风险预测工具的巨大潜力。本文重点介绍了qMRI技术,包括化学位移编码磁共振成像(chemical shift encoding magnetic resonance imaging,CSE-MRI)、磁共振波谱(magnetic resonance spectroscopy,MRS)、T1/T2 mapping及纹理分析等的优势与局限性,及其在肌营养不良症、代谢性疾病及骨关节炎相关退行性病变等疾病诊断与监测中的临床应用。研究显示,qMRI技术能够精确量化肌肉FI,有望成为肌肉病理领域无创诊断的重要工具。 展开更多
关键词 定量磁共振成像 脂肪定量 肌肉脂肪浸润 生物标志物 无创诊断
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锆基金属玻璃的电子探针元素定量面分析方法
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作者 李明辉 吴金金 +3 位作者 葛立发 郜鲜辉 宋武林 周芃 《理化检验(物理分册)》 2026年第2期23-26,共4页
采用电子探针方法对锆基金属玻璃进行元素定量面分析,研究不同分析模式和加速电压对面分析结果的影响,并优化了工作曲线。结果表明:选择Peak Search模式,在加速电压为15 kV的条件下,利用两点法定量曲线可以得到准确性较高的面分析结果。
关键词 电子探针 锆基金属玻璃 面分析 定量化 加速电压
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Simultaneous quantification of flavonol glycosides, terpene lactones, polyphenols and carboxylic acids in Ginkgo biloba leaf extract by UPLC-QTOF-MS^E based metabolomic approach 被引量:10
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作者 赵一懿 郭洪祝 +1 位作者 陈有根 傅欣彤 《Journal of Chinese Pharmaceutical Sciences》 CAS CSCD 2017年第11期789-804,共16页
Abstract: In the present study, we established an ultra performance liquid chromatography coupled with time-of-flight mass spectrometry (UPLC-QTOF-MSE) method to simultaneously quantify 33 components in Ginkgo bilo... Abstract: In the present study, we established an ultra performance liquid chromatography coupled with time-of-flight mass spectrometry (UPLC-QTOF-MSE) method to simultaneously quantify 33 components in Ginkgo biloba leaf extracts (GBEs), including 17 flavonol glycosides, five terpene trilactones (TTLs), four polyphenols and seven carboxylic acids. This optimized method was successfully applied to analyze the explicit compositions of GBE samples collected from different places. Furthermore, the data were processed through unsupervised principal component analysis (PCA) and supervised orthogonal partial least squared discrimination analysis (OPLS-DA) to evaluate the quality and compare the differences between the samples according to the contents of the 33 chemical constituents. Bilobalide, protocatechuic acid, shikimic acid, quinic acid, ginkgolide B, ginkgolide J, kaempferol-3-O-rutinoside, isorhamnetin-3-O-rutinoside, quercetin-3-O-ct-L-rhamnopyranocyl-2"-(6'"-p-coumaroyl)-β-D-glucoside and rutin were recognized as characteristic chemical markers that contributed most to control the quality of GBEs. Based on the fact that GBEs should be standardized with the characteristic components as quality control chemical markers, it is most important to maintain the quality of GBEs stable and reliable, and this method also provided a good strategy to further rectify and standardize the GBEs market. 展开更多
关键词 Ginkgo biloba L. leaf extract UPLC-QTOF-MS^E PCA Multi-components quantification Genuine flavonol glycoside
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运用Real-time quantification PCR方法建立副溶血性弧菌在即食虾中的生长预测模型 被引量:5
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作者 彭织云 王敬敬 +2 位作者 唐晓阳 潘迎捷 赵勇 《食品工业科技》 CAS CSCD 北大核心 2013年第8期108-110,共3页
运用Real-time quantification PCR(real-time qPCR)方法建立副溶血性弧菌在即食虾中生长预测模型。首先构建质粒标准品,梯度稀释后建立标准曲线,然后用Real-time qPCR方法检测虾中副溶血性弧菌的数量,最后建立37℃下即食虾中副溶血性... 运用Real-time quantification PCR(real-time qPCR)方法建立副溶血性弧菌在即食虾中生长预测模型。首先构建质粒标准品,梯度稀释后建立标准曲线,然后用Real-time qPCR方法检测虾中副溶血性弧菌的数量,最后建立37℃下即食虾中副溶血性弧菌生长预测模型,并与传统涂布计数方法进行比较。结果表明,Real-time qPCR方法和传统计数方法均可建立Gmopertz模型、Logistic模型和Richards模型,模型拟合的相关系数R2均在0.9以上。基于Real-timeqPCR方法省时省力、特异性好等优点,用Real-time qPCR方法建立微生物预测模型是未来预测微生物学领域的一种发展趋势。 展开更多
关键词 REAL-TIME quantification PCR 副溶血性弧菌 生长预测模型
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一种基于HAZOP-LOPA的碱回收燃烧工段安全仪表系统设计方法
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作者 汤伟 郑晓虎 +1 位作者 王孟效 王其林 《中国造纸》 北大核心 2026年第1期149-156,共8页
针对当前造纸工业安全仪表系统(SIS)设计方法存在的风险分析碎片化、定量评估不足等问题,本研究以碱回收燃烧工段汽包控制部分SIS设计为例,提出一种基于危险与可操作性分析-保护层分析(HAZOP-LOPA)的SIS定级及设计方法。首先对碱回收燃... 针对当前造纸工业安全仪表系统(SIS)设计方法存在的风险分析碎片化、定量评估不足等问题,本研究以碱回收燃烧工段汽包控制部分SIS设计为例,提出一种基于危险与可操作性分析-保护层分析(HAZOP-LOPA)的SIS定级及设计方法。首先对碱回收燃烧工段进行工艺流程节点划分,并设计对应的风险概率-后果二维风险矩阵,通过HAZOP方法系统识别该工段的潜在偏差与风险场景,结合LOPA分析构建独立保护层量化模型;然后基于风险传导特性建立保护层分析-安全完整性等级(LOPA-SIL)动态映射关系,对SIS等级进行合理定级,最后根据定级结果进行SIS的设计,并通过系统失效概率、剩余风险值等指标验证系统的有效性。结果表明,该方法可成功识别2项高风险场景并判定需增设SIL2级SIS,改进后将风险概率成功降至企业可接受水平(<1.0×10-6/年)。 展开更多
关键词 碱回收燃烧工段 HAZOP-LOPA 安全完整性等级 安全仪表系统 风险量化
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Quantification of seven phenylpropanoid compounds in Chinese Cinnamomi Cortex and Ramulus by HPLC 被引量:3
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作者 袁鹏飞 马雅静 +7 位作者 苏丹 尚明英 徐风 刘广学 Niloufar Iranmanesh 李兰芳 姜廷良 蔡少青 《Journal of Chinese Pharmaceutical Sciences》 CAS CSCD 2015年第9期591-599,共9页
In the present study, we developed and validated a high-performance liquid chromatography method for the simultaneous determination of seven phenylpropanoid compounds (2-hydroxyl cinnamaldehyde, coumarin, cinnamyl al... In the present study, we developed and validated a high-performance liquid chromatography method for the simultaneous determination of seven phenylpropanoid compounds (2-hydroxyl cinnamaldehyde, coumarin, cinnamyl alcohol, cinnamic acid, 2-methoxy cinnamic acid, cinnamaldehyde and 2-methoxy cinnamaldehyde) in Cinnamomi Cortex and Cinnamomi Ramulus. The levels of seven phenylpropanoid compounds in Cinnamomi Cortex and Cinnamomi Ramulus were compared using this method. A total of 48 samples (27 Cinnamomi Cortex and 21 Cinnamomi Ramulus) were purchased in China and analyzed. Quantities of seven phenylpropanoid compounds ranged from 17.5 to 61.6 mg/g in Cinnamomi Cortex and ranged from 9.91 to 23.4 mg/g in Ciunamomi Ramulus. The level of 2-methoxy cinnamic acid in the Cinnamomi Cortex samples was below the LOD, whereas it ranged from 0 to 0.119 mg/g in the Cinnamomi Ramulus samples. The (cinnamyl alcohol+cinnamic acid)/cinnamaldehyde ratios (R346) of Ciunamomi Cortex and Cinnamomi Ramulus ranged from 0.0121 to 0.0467 and 0.0598 to 0.182, respectively. This ratio could be used to discriminate Cinnamomi Cortex (〈0.05) and Cinnamomi Ramulus (〉0.05). The extraction rates (Dn) of seven compounds in boiling water were different, with the lowest dissolution for cinnamaldehyde (〈3%) and the highest for cinnamic acid (about 60%). 展开更多
关键词 quantification Phenylpropanoid compounds Cinnamomi Cortex Cinnamomi Ramulus High-performance liquid chromatography
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基于模糊层次分析法的激光处置效能评估方法研究
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作者 王端 胡豪 +2 位作者 谢全威 徐国顺 袁道任 《科技创新与应用》 2026年第5期16-19,共4页
随着低空经济的快速发展,无人机的普遍使用带来诸多安全风险和隐患,激光处置作为低空安全防控的一种新质手段,其效能评估对于考核系统性能、推动工程化应用具有十分重要的意义。基于此,该文提出一种基于模糊层次分析法的激光处置效能评... 随着低空经济的快速发展,无人机的普遍使用带来诸多安全风险和隐患,激光处置作为低空安全防控的一种新质手段,其效能评估对于考核系统性能、推动工程化应用具有十分重要的意义。基于此,该文提出一种基于模糊层次分析法的激光处置效能评估方法,该方法利用层次分析法计算各类指标综合权重,并基于模糊数学的隶属度理论进一步将评价量化,从而确定系统的效能评级,对提高激光处置效能评估的准确性、可靠性具有积极意义。 展开更多
关键词 低空安全 模糊层次分析法 激光处置 效能评估 权重矩阵量化
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Quantification of eugenol and bancroftione in Caryophylli Fructus using high-performance liquid chromatography 被引量:1
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作者 刘淑娟 林宗涛 +1 位作者 王弘 陈世忠 《Journal of Chinese Pharmaceutical Sciences》 CAS 2010年第6期459-463,共5页
For the first time, we have utilized high-performance liquid chromatography (HPLC) to simultaneously quantify the eugenol and bancroffione in Caryophylli Fructus. The optimized parameters included: Inertsil ODS-4 c... For the first time, we have utilized high-performance liquid chromatography (HPLC) to simultaneously quantify the eugenol and bancroffione in Caryophylli Fructus. The optimized parameters included: Inertsil ODS-4 column (150 mm×4.6 mm, 5 μm); column temperature: 35 ℃; mobile phase: methanol water (65:35, v/v); flow rate: 1.0 mL/min; detection wavelength: 280 nm. Eugenol and bancroftione showed good linear relationships with peak areas within the range of (0.0998 0.8982) mg/mL (r = 0.9999) and (0.1474-1.3266) mg/mL (r = 0.9999), respectively. The average recoveries were 102.52% and 100.96% for eugenol and bancroftione, respectively. Our results showed that the established method is simple, rapid, and accurate with good reproducibility to evaluate the quality of Caryophylli Fructus. 展开更多
关键词 Caryophylli Fructus EUGENOL Bancroftione quantification HPLC
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Quantification of the active ingredient quercetin of “Guangdong Wang-bu-liu-xing” by high-performance liquid chromatography with UV detection 被引量:1
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作者 曾颂 韩秀奇 李书渊 《Journal of Chinese Pharmaceutical Sciences》 CAS CSCD 2013年第1期101-105,共5页
High-performance liquid chromatography with UV detection was used for the quantification of the flavonoid quercetin, the active compound found in "Guangdong Wang-bu-liu-xing". The method was developed and demonstrat... High-performance liquid chromatography with UV detection was used for the quantification of the flavonoid quercetin, the active compound found in "Guangdong Wang-bu-liu-xing". The method was developed and demonstrated to provide superior performance over other commonly documented methods. This HPLC assay achieved high specificity through the use of a reversed-phase C18 column eluted with a mobile phase of methanol-0.4% (v/v) phosphoric acid (50:50, v/v) over the course of 30 min. UV detection at 360 nm was used. This analytical method provided excellent precision and a mean recovery of 99%, demonstrated by repeated analysis of 11 sample groups. Because of its high performance and simplicity, this HPLC assay can be readily utilized as a practical method for the quality control of active compounds extracted from Guangdong Wang-bu-liu-xing. 展开更多
关键词 Guangdong Wang-bu-liu-xing quantification HPLC QUERCETIN
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Real-Time PCR Technique and Its Application in Quantification of Plant Nucleic Acid Molecules 被引量:8
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作者 刘进元 《Acta Botanica Sinica》 CSCD 2003年第6期631-637,共7页
Real-time PCR is a closed DNA amplification system that skillfully integrates biochemical, photoelectric and computer techniques. Fluorescence data acquired once per cycle provides rapid absolute quantification of ini... Real-time PCR is a closed DNA amplification system that skillfully integrates biochemical, photoelectric and computer techniques. Fluorescence data acquired once per cycle provides rapid absolute quantification of initial template copy numbers as PCR products are generated. This technique significantly simplifies and accelerates the process of producing reproducible quantification of nucleic acid molecules. It not only is a sensitive, accurate and rapid quantitative method, but it also provides an easier way to calculate the absolute starting copy number of nucleic acid molecules to be tested. Together with molecular bio-techniques, like microarray, real-time PCR will play a very important role in many aspects of molecular life science such as functional gene analysis and disease molecular diagnostics. This review introduces the detailed principles and application of the real-time PCR technique, describes a recently developed system for exact quantification of AUX/IAA genes In Arabidopsis, and discusses the problems with the real-time PCR process. 展开更多
关键词 real-time PCR technique quantification of plant nucleic acid molecules gene expression molecular medicine
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