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IndRT-GCNets: Knowledge Reasoning with Independent Recurrent Temporal Graph Convolutional Representations
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作者 Yajing Ma Gulila Altenbek Yingxia Yu 《Computers, Materials & Continua》 SCIE EI 2024年第1期695-712,共18页
Due to the structural dependencies among concurrent events in the knowledge graph and the substantial amount of sequential correlation information carried by temporally adjacent events,we propose an Independent Recurr... Due to the structural dependencies among concurrent events in the knowledge graph and the substantial amount of sequential correlation information carried by temporally adjacent events,we propose an Independent Recurrent Temporal Graph Convolution Networks(IndRT-GCNets)framework to efficiently and accurately capture event attribute information.The framework models the knowledge graph sequences to learn the evolutionary represen-tations of entities and relations within each period.Firstly,by utilizing the temporal graph convolution module in the evolutionary representation unit,the framework captures the structural dependency relationships within the knowledge graph in each period.Meanwhile,to achieve better event representation and establish effective correlations,an independent recurrent neural network is employed to implement auto-regressive modeling.Furthermore,static attributes of entities in the entity-relation events are constrained andmerged using a static graph constraint to obtain optimal entity representations.Finally,the evolution of entity and relation representations is utilized to predict events in the next subsequent step.On multiple real-world datasets such as Freebase13(FB13),Freebase 15k(FB15K),WordNet11(WN11),WordNet18(WN18),FB15K-237,WN18RR,YAGO3-10,and Nell-995,the results of multiple evaluation indicators show that our proposed IndRT-GCNets framework outperforms most existing models on knowledge reasoning tasks,which validates the effectiveness and robustness. 展开更多
关键词 Knowledge reasoning entity and relation representation structural dependency relationship evolutionary representation temporal graph convolution
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Assessment of Dependent Performance Shaping Factors in SPAR-H Based on Pearson Correlation Coefficient 被引量:1
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作者 Xiaoyan Su Shuwen Shang +2 位作者 Zhihui Xu Hong Qian Xiaolei Pan 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第2期1813-1826,共14页
With the improvement of equipment reliability,human factors have become the most uncertain part in the system.The standardized Plant Analysis of Risk-Human Reliability Analysis(SPAR-H)method is a reliable method in th... With the improvement of equipment reliability,human factors have become the most uncertain part in the system.The standardized Plant Analysis of Risk-Human Reliability Analysis(SPAR-H)method is a reliable method in the field of human reliability analysis(HRA)to evaluate human reliability and assess risk in large complex systems.However,the classical SPAR-H method does not consider the dependencies among performance shaping factors(PSFs),whichmay cause overestimation or underestimation of the risk of the actual situation.To address this issue,this paper proposes a new method to deal with the dependencies among PSFs in SPAR-H based on the Pearson correlation coefficient.First,the dependence between every two PSFs is measured by the Pearson correlation coefficient.Second,the weights of the PSFs are obtained by considering the total dependence degree.Finally,PSFs’multipliers are modified based on the weights of corresponding PSFs,and then used in the calculating of human error probability(HEP).A case study is used to illustrate the procedure and effectiveness of the proposed method. 展开更多
关键词 Reliability evaluation human reliability analysis SPAR-H performance shaping factors dependENCE pearson correlation analysis
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Theoretical characterization of the temperature-dependent saturation magnetization of magnetic metallic materials
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作者 吴金龙 董攀 +6 位作者 贺屹 马艳丽 李梓源 姚沁远 邱俊 麻建坐 李卫国 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第7期577-585,共9页
Based on the force-heat equivalence energy density principle,a theoretical model for magnetic metallic materials is developed,which characterizes the temperature-dependent magnetic anisotropy energy by considering the... Based on the force-heat equivalence energy density principle,a theoretical model for magnetic metallic materials is developed,which characterizes the temperature-dependent magnetic anisotropy energy by considering the equivalent relationship between magnetic anisotropy energy and heat energy;then the relationship between the magnetic anisotropy constant and saturation magnetization is considered.Finally,we formulate a temperature-dependent model for saturation magnetization,revealing the inherent relationship between temperature and saturation magnetization.Our model predicts the saturation magnetization for nine different magnetic metallic materials at different temperatures,exhibiting satisfactory agreement with experimental data.Additionally,the experimental data used as reference points are at or near room temperature.Compared to other phenomenological theoretical models,this model is considerably more accessible than the data required at 0 K.The index included in our model is set to a constant value,which is equal to 10/3 for materials other than Fe,Co,and Ni.For transition metals(Fe,Co,and Ni in this paper),the index is 6 in the range of 0 K to 0.65T_(cr)(T_(cr) is the critical temperature),and 3 in the range of 0.65T_(cr) to T_(cr),unlike other models where the adjustable parameters vary according to each material.In addition,our model provides a new way to design and evaluate magnetic metallic materials with superior magnetic properties over a wide range of temperatures. 展开更多
关键词 magnetic metallic materials temperature dependent saturation magnetization MODELING
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BCCLR:A Skeleton-Based Action Recognition with Graph Convolutional Network Combining Behavior Dependence and Context Clues
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作者 Yunhe Wang Yuxin Xia Shuai Liu 《Computers, Materials & Continua》 SCIE EI 2024年第3期4489-4507,共19页
In recent years,skeleton-based action recognition has made great achievements in Computer Vision.A graph convolutional network(GCN)is effective for action recognition,modelling the human skeleton as a spatio-temporal ... In recent years,skeleton-based action recognition has made great achievements in Computer Vision.A graph convolutional network(GCN)is effective for action recognition,modelling the human skeleton as a spatio-temporal graph.Most GCNs define the graph topology by physical relations of the human joints.However,this predefined graph ignores the spatial relationship between non-adjacent joint pairs in special actions and the behavior dependence between joint pairs,resulting in a low recognition rate for specific actions with implicit correlation between joint pairs.In addition,existing methods ignore the trend correlation between adjacent frames within an action and context clues,leading to erroneous action recognition with similar poses.Therefore,this study proposes a learnable GCN based on behavior dependence,which considers implicit joint correlation by constructing a dynamic learnable graph with extraction of specific behavior dependence of joint pairs.By using the weight relationship between the joint pairs,an adaptive model is constructed.It also designs a self-attention module to obtain their inter-frame topological relationship for exploring the context of actions.Combining the shared topology and the multi-head self-attention map,the module obtains the context-based clue topology to update the dynamic graph convolution,achieving accurate recognition of different actions with similar poses.Detailed experiments on public datasets demonstrate that the proposed method achieves better results and realizes higher quality representation of actions under various evaluation protocols compared to state-of-the-art methods. 展开更多
关键词 Action recognition deep learning GCN behavior dependence context clue self-attention
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Modified DS np Chart Using Generalized Multiple Dependent State Sampling under Time Truncated Life Test
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作者 Wimonmas Bamrungsetthapong Pramote Charongrattanasakul 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第3期2471-2495,共25页
This study presents the design of a modified attributed control chart based on a double sampling(DS)np chart applied in combination with generalized multiple dependent state(GMDS)sampling to monitor the mean life of t... This study presents the design of a modified attributed control chart based on a double sampling(DS)np chart applied in combination with generalized multiple dependent state(GMDS)sampling to monitor the mean life of the product based on the time truncated life test employing theWeibull distribution.The control chart developed supports the examination of the mean lifespan variation for a particular product in the process of manufacturing.Three control limit levels are used:the warning control limit,inner control limit,and outer control limit.Together,they enhance the capability for variation detection.A genetic algorithm can be used for optimization during the in-control process,whereby the optimal parameters can be established for the proposed control chart.The control chart performance is assessed using the average run length,while the influence of the model parameters upon the control chart solution is assessed via sensitivity analysis based on an orthogonal experimental design withmultiple linear regression.A comparative study was conducted based on the out-of-control average run length,in which the developed control chart offered greater sensitivity in the detection of process shifts while making use of smaller samples on average than is the case for existing control charts.Finally,to exhibit the utility of the developed control chart,this paper presents its application using simulated data with parameters drawn from the real set of data. 展开更多
关键词 Modified DS np chart generalizedmultiple dependent state sampling time truncated life test Weibull distribution average run length average sample size
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Path-dependent speciation in dynamic fitness landscapes
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作者 Min-Lan Li Chao Wang Rui-Wu Wang 《Zoological Research(Diversity and Conservation)》 2024年第2期133-140,共8页
Species is a fundamental concept in evolutionary biology and biodiversity.However,existing species definitions are often influenced by artificial factors or are challenging in practical application,leading to confusio... Species is a fundamental concept in evolutionary biology and biodiversity.However,existing species definitions are often influenced by artificial factors or are challenging in practical application,leading to confusion in species classification.Due to uncertain environmental changes and random genetic drift,the fitness expectations of a population may shift,causing species to evolve to a new evolutionary state based on their current instantaneous fitness within a dynamic fitness landscape.This contrasts with the classic static fitness landscape,where fitness expectations are constant.In a dynamic fitness landscape,speciation may exhibit path dependence,where the evolution of traits follows a probabilistic path,creating feedback that shapes evolutionary trajectories.The path-dependent evolutionary mechanism suggests that species survival within an ecosystem is not directly determined by their fitness but by the probability of their evolutionary pathways.This model also indicates that species can coexist with varying probabilities under limited environmental pressures.Consequently,new species,cryptic species,or sympatric species may emerge via path-dependent evolutionary processes.Within this framework,we developed a mathematical species concept,which may guide future species classification methodologies. 展开更多
关键词 BIODIVERSITY Ecological/evolutionary model Fitness landscape Stochastic process Path dependence
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Fuzzy Inventory Model under Selling Price Dependent Demand and Variable Deterioration with Fully Backlogged Shortages
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作者 Tanzim S. Shaikh Santosh P. Gite 《American Journal of Operations Research》 2024年第2期87-103,共17页
The objective is to develop a model considering demand dependent on selling price and deterioration occurs after a certain period of time, which follows two-parameter Weibull distribution. Shortages are allowed and fu... The objective is to develop a model considering demand dependent on selling price and deterioration occurs after a certain period of time, which follows two-parameter Weibull distribution. Shortages are allowed and fully backlogged. Fuzzy optimal solution is obtained by considering hexagonal fuzzy numbers and for defuzzification Graded Mean Integration Representation Method. A numerical example is provided for the illustration of crisp and fuzzy, both models. To observe the effect of changes in parameters, sensitivity analysis is carried out. 展开更多
关键词 DETERIORATION Selling Price dependent Demand Fully Backlogged Hexagonal Fuzzy Numbers Graded Mean Integration Representation Method
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A Study of Radiation-Induced Telomere Instability Using Multiplex Ligation-Dependent Probe Amplification (MLPA)
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作者 Alan Chant Ahmad Chaudary Christina M. Kraemer-Chant 《Advances in Biological Chemistry》 CAS 2024年第3期73-85,共13页
The integrity of the chromosomes for two WIL2-derived lymphoblastoid cell lines (TK6 and WTK1) in the presence and absence of ionizing radiation was analyzed by Multiplex Ligation-Dependent Probe Amplification (MLPA).... The integrity of the chromosomes for two WIL2-derived lymphoblastoid cell lines (TK6 and WTK1) in the presence and absence of ionizing radiation was analyzed by Multiplex Ligation-Dependent Probe Amplification (MLPA). The TK6 cell line has the native p53 tumor-suppressor gene, whereas WTK1 cells contain a p53 mutation. Each cell line was isolated pre- and post-irradiation (2 and 3 Gy) and analyzed by MLPA. The impact of irradiation on these two cell lines was investigated using probes that target specific regions on chromosomes associated with subtelomeric regions. Results indicate that WTK1 and TK6 are impacted differently after irradiation, and that each cell line presents its own unique MLPA profile. The most notable differences are the appearance of a number of probes in the post-irradiated MLPA profile that are not present in the controls, and two unique probe signals only seen in WTK1 cells. These results build on our previous studies that indicate how different human cell lines can be affected by radiation in significantly different ways depending on the presence or absence of wild type p53. 展开更多
关键词 Ionizing Radiation Multiplex Ligation-dependent Probe Amplification (MLPA) p53 Tumor Suppressor Telomere Instability
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Inverse Spectral Problem for Sturm-Liouville Operator with Boundary and Jump Conditions Dependent on the Spectral Parameter
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作者 Hui Zhao Jijun Ao 《Journal of Applied Mathematics and Physics》 2024年第3期982-996,共15页
In this paper, the inverse spectral problem of Sturm-Liouville operator with boundary conditions and jump conditions dependent on the spectral parameter is investigated. Firstly, the self-adjointness of the problem an... In this paper, the inverse spectral problem of Sturm-Liouville operator with boundary conditions and jump conditions dependent on the spectral parameter is investigated. Firstly, the self-adjointness of the problem and the eigenvalue properties are given, then the asymptotic formulas of eigenvalues and eigenfunctions are presented. Finally, the uniqueness theorems of the corresponding inverse problems are given by Weyl function theory and inverse spectral data approach. 展开更多
关键词 Inverse Problem Sturm-Liouville Operator Weyl Function Eigenparameter-dependent Jump Conditions
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Thermomechanical Dynamics (TMD) and Bifurcation-Integration Solutions in Nonlinear Differential Equations with Time-Dependent Coefficients
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作者 Hiroshi Uechi Lisa Uechi Schun T. Uechi 《Journal of Applied Mathematics and Physics》 2024年第5期1733-1743,共11页
The new independent solutions of the nonlinear differential equation with time-dependent coefficients (NDE-TC) are discussed, for the first time, by employing experimental device called a drinking bird whose simple ba... The new independent solutions of the nonlinear differential equation with time-dependent coefficients (NDE-TC) are discussed, for the first time, by employing experimental device called a drinking bird whose simple back-and-forth motion develops into water drinking motion. The solution to a drinking bird equation of motion manifests itself the transition from thermodynamic equilibrium to nonequilibrium irreversible states. The independent solution signifying a nonequilibrium thermal state seems to be constructed as if two independent bifurcation solutions are synthesized, and so, the solution is tentatively termed as the bifurcation-integration solution. The bifurcation-integration solution expresses the transition from mechanical and thermodynamic equilibrium to a nonequilibrium irreversible state, which is explicitly shown by the nonlinear differential equation with time-dependent coefficients (NDE-TC). The analysis established a new theoretical approach to nonequilibrium irreversible states, thermomechanical dynamics (TMD). The TMD method enables one to obtain thermodynamically consistent and time-dependent progresses of thermodynamic quantities, by employing the bifurcation-integration solutions of NDE-TC. We hope that the basic properties of bifurcation-integration solutions will be studied and investigated further in mathematics, physics, chemistry and nonlinear sciences in general. 展开更多
关键词 The Nonlinear Differential Equation with Time-dependent Coefficients The Bifurcation-Integration Solution Nonequilibrium Irreversible States Thermomechanical Dynamics (TMD)
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Assessment of Nephro-, Hepato-, and Sex-Dependent Toxicity of Carmoisine Exposure in Albino Rats
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作者 Ibioku Elekima Uchechukwu Achor Obisike +5 位作者 Holy Brown Helen Anthony Waribo Ngozi Brisibe Ibitoroko George-Opuda Adline Ben-Chioma Donatus Onwuli 《Journal of Biosciences and Medicines》 2023年第9期63-78,共16页
Aim: To evaluate chronic exposure of carmoisine at ADI doses on some hepatocellular and renal parameters of male and female albino rats as well as to determine sex-dependent toxicity. Study Design: The study involves ... Aim: To evaluate chronic exposure of carmoisine at ADI doses on some hepatocellular and renal parameters of male and female albino rats as well as to determine sex-dependent toxicity. Study Design: The study involves treatment for 30, 60, and 90 days. Each phase consists of 40 rats, divided into treatment and control groups. The treated groups were orally administered with 4.0 mg/kg of carmoisine daily for the periods of 30, 60, and 90 days. Methodology: At the end of the treatment, the rats were allowed to fast for 18 hours followed by the collection of 5 ml of whole blood specimens by means of cardiac puncture into Lithium Heparin bottles and fluoride oxalate bottles (for glucose only). Plasma obtained was analyzed for glucose (GLU), AST, ALT, ALP, creatinine (CRT), and urea. Hepatic and Renal tissues collected were fixed in 10% formol saline and later examined histologically using H&E stain. Statistical data analysis was done using GraphPad Prism version 9.02. Results: Glucose indicated significant increases after 30, 60, and 90 days of chronic treatment at ADI doses. Urea, Creatinine, AST, ALT and ALP showed significantly higher values after 60 and 90 days of treatment (except creatinine in male rats and ALP in female rats after 60 and 90 days respectively). Hepatic distortions, vacuolation, compression of central vein were seen in the liver section while distortion of proximal and distal tubules, and inflammation of the glomerulus were observed in the renal tissue of the treated rats. Conclusion: The administration of camoisine over a period of 30 days at ADI dose did not indicate hepatocellullar and renal derangements as well histological distortions in liver, and kidneys. However, after 60 and 90 days, mild hepatocellular, and renal derangements were seen. No sex-dependent toxicity was observed. 展开更多
关键词 Carmoisine TOXICITY Liver Enzymes Renal Tissue Sex-dependent Azo Dye CREATININE UREA
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pH值调控方法对剩余污泥与柑橘废渣厌氧共发酵产酸影响 被引量:2
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作者 董姗燕 罗进财 +3 位作者 王欣芸 廖靖莹 孙鸿 朱易春 《中国环境科学》 EI CAS CSCD 北大核心 2024年第1期167-177,共11页
考察不同pH值调控方法对剩余污泥和柑橘废渣共发酵系统的产酸性能影响,结果表明:持续调节pH值为6可以提高共发酵系统的增溶过程,促进糖类物质水解,增强产酸和产甲烷过程,VFA产量和累积甲烷产量分别是空白组的1.36倍和1.25倍;提高共发酵... 考察不同pH值调控方法对剩余污泥和柑橘废渣共发酵系统的产酸性能影响,结果表明:持续调节pH值为6可以提高共发酵系统的增溶过程,促进糖类物质水解,增强产酸和产甲烷过程,VFA产量和累积甲烷产量分别是空白组的1.36倍和1.25倍;提高共发酵系统中水解细菌和发酵产酸细菌的菌群丰度,促使甲烷生成途径从乙酰分解途径转向氢化营养途径.调节初始pH值为10可以有效促进共发酵系统中溶解性有机物的释放和达到快速水解的目的,促进产酸性能,但对产甲烷过程有抑制作用. 展开更多
关键词 剩余污泥 柑橘废渣 共发酵 ph值调节 挥发性脂肪酸
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Substrate-dependent photoreactivities of BiOBr nanoplates prepared at different pH values 被引量:4
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作者 艾智慧 王吉玲 张礼知 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2015年第12期2145-2154,共10页
In this study,we showed that BiO Br nanoplates prepared at different pH values have substratedependent photocatalytic activities under visible-light irradiation. The BiO Br nanoplates synthesized at pH 1(BOB-1) degr... In this study,we showed that BiO Br nanoplates prepared at different pH values have substratedependent photocatalytic activities under visible-light irradiation. The BiO Br nanoplates synthesized at pH 1(BOB-1) degraded salicylic acid more effectively than did those obtained at pH 3(BOB-3),but the order of their photocatalytic activities in rhodamine B(RhB) degradation were reversed. Electrochemical Mott–Schottky and zeta-potential measurements showed that BOB-1 had a more positive valence band and lower surface charge,leading to superior photocatalytic activity in salicylic acid degradation under visible light. However,BOB-3 was more powerful in RhB degradation because larger numbers of superoxide radicals were generated via electron injection from the excited RhB to its more negative conduction band under visible-light irradiation; this was confirmed using active oxygen species measurements and electron spin resonance analysis. This study deepens our understanding of the origins of organic-pollutant-dependent photoreactivities of semiconductors,and will help in designing highly active photocatalysts for environmental remediation. 展开更多
关键词 DEGRADATION Visible light Substrate dependent photoreactivity Bismuth oxybromide nanoplate Rhodamine B Salicylic acid
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改进和优化黑果枸杞及其制品中花青素测定的pH示差法 被引量:1
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作者 谭亮 杲秀珍 +2 位作者 王环 赵静 李玉林 《食品与发酵工业》 CAS CSCD 北大核心 2024年第4期267-278,共12页
建立一种基于美国官方分析化学师协会(Association of Official Analytical Chemists,AOAC)方法检测黑果枸杞及其制品中花青素含量的改进pH示差法。考察了黑果枸杞及其制品中花青素的最佳提取和检测条件,通过液相色谱-三重四级杆串联质... 建立一种基于美国官方分析化学师协会(Association of Official Analytical Chemists,AOAC)方法检测黑果枸杞及其制品中花青素含量的改进pH示差法。考察了黑果枸杞及其制品中花青素的最佳提取和检测条件,通过液相色谱-三重四级杆串联质谱法鉴别出黑果枸杞中花青素的具体化学结构,并计算出混合花青素的平均摩尔质量。通过分光光度法测得混合花青素的平均摩尔消光系数,对改进后的pH示差法进行方法学验证和花青素的含量测定。结果显示,最佳提取和检测条件如下:黑果枸杞花青素提取溶剂为盐酸-80%(体积分数)乙醇(3∶97,体积比),料液比为1∶100(g∶mL),提取温度为50℃,提取时间为30 min,缓冲溶液稀释5倍后静置平衡20 min。液相色谱-三重四级杆串联质谱法鉴别黑果枸杞中主要以矮牵牛素类花青素为主(占97.96%),黑果枸杞特有的混合花青素平均摩尔质量为912.7 g/mol,平均摩尔消光系数为29591 L/(mol·cm)。pH示差法改进后能够满足方法学验证要求,固体样品和液体样品最低检出限分别为28.2 mg/100 g、0.282 mg/100 mL。方法改进后花青素提取增长率均大于20%,静置平衡20 min后单次检测结果精密度小于0.3%。以矮牵牛素类花青素代替矢车菊素-3-O-葡萄糖苷计算花青素含量平均提高了2.41倍,能真实地反映黑果枸杞及其制品中花青素的含量。 展开更多
关键词 黑果枸杞及其制品 花青素 AOAC法 ph示差法改进 提取和检测条件优化 液相色谱-三重四级杆串联质谱法鉴别 平均摩尔质量和平均摩尔消光系数优化
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两种调理剂对水稻土pH值和重金属吸收的影响
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作者 张璐 文石林 +2 位作者 上官方钦 秦松 张会民 《中国土壤与肥料》 CAS CSCD 北大核心 2024年第1期79-85,共7页
探明两种调理剂对近中性水稻土pH值、重金属有效性和水稻吸收的影响,及其与土壤性质的关系,为调理剂的科学开发及合理施用提供科学依据。选取水淬高炉渣源调理剂(T1)及其腐殖质改性调理剂(T2),分别设置2个施用量梯度(T1L、T1H和T2L、T2... 探明两种调理剂对近中性水稻土pH值、重金属有效性和水稻吸收的影响,及其与土壤性质的关系,为调理剂的科学开发及合理施用提供科学依据。选取水淬高炉渣源调理剂(T1)及其腐殖质改性调理剂(T2),分别设置2个施用量梯度(T1L、T1H和T2L、T2H),通过盆栽试验分析了两种调理剂及不同用量对土壤pH值、有效硅、镉、锌、铜含量,以及水稻籽粒和秸秆镉、锌、铜含量的影响。与对照(CK)相比,2个施用T1调理剂处理土壤pH值分别升高0.64和1.02,2个施用T2调理剂处理pH值分别升高0.27和0.56(P<0.05),土壤pH值随调理剂施用量的增加而增加。T1L和T1H处理土壤有效硅含量与CK相比分别提高5和22倍(P<0.05),且显著高于施用T2调理剂处理。与CK相比,T1H处理土壤有效镉、锌、铜含量分别降低37.21%、45.57%和95.30%(P<0.05);T2L和T2H处理土壤有效锌含量分别降低31.55%和30.67%,有效铜含量分别降低6.53%和19.32%(P<0.05)。与CK相比,T1L和T1H水稻籽粒锌含量分别降低23.44%和18.12%(P<0.05);施用T2调理剂后,籽粒和秸秆锌、铜含量无显著变化。土壤pH值、有效硅含量与土壤有效镉、锌、铜含量呈显著或极显著负相关,土壤有效硅含量与籽粒、秸秆镉含量呈显著负相关。研究表明,在近中性水稻土上施用富含硅的强碱性调理剂,既有利于提高土壤p H值和有效硅含量,又可有效降低土壤重金属有效性及其水稻吸收量。 展开更多
关键词 调理剂 水稻土 ph 有效硅 重金属
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面向栽培基质的二氧化钛电极EGFET pH传感器设计
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作者 张西良 高涵 +3 位作者 张家祺 徐云峰 陈成 陆海燕 《排灌机械工程学报》 CSCD 北大核心 2024年第7期743-748,共6页
针对农业生产中栽培基质直接在线检测pH准确性差的问题,采用化学腐蚀法,制备出具有氢离子敏感特性和超亲水特性的二氧化钛(TiO_(2))电极,并且采用退火工艺以提高电极表面硬度;将TiO_(2)电极与金属氧化物场效应晶体管(MOSFET)组合成基于... 针对农业生产中栽培基质直接在线检测pH准确性差的问题,采用化学腐蚀法,制备出具有氢离子敏感特性和超亲水特性的二氧化钛(TiO_(2))电极,并且采用退火工艺以提高电极表面硬度;将TiO_(2)电极与金属氧化物场效应晶体管(MOSFET)组合成基于延伸式栅极场效应晶体管(EGFET)的pH传感器.测试得到传感器灵敏度为0.05063 V/pH,重复性试验的变异系数最大为0.0057.测试结果表明该传感器具有良好的灵敏度、重复性和稳定性.选取4种典型栽培基质进行pH在线检测应用试验,pH检测误差的绝对值最大为0.18,经过温度补偿后误差的绝对值最大为0.11;使用后电极表面的亲水性依旧保持良好.应用试验结果表明,该传感器适用于栽培基质pH在线检测. 展开更多
关键词 ph传感器 二氧化钛电极 延伸式栅极场效应晶体管 栽培基质 ph在线检测
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基于逆Leidenfrost效应的多孔地聚合物微球孔结构及pH缓冲性能
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作者 李方贤 王亚松 +2 位作者 张志博 韦江雄 余其俊 《建筑材料学报》 EI CAS CSCD 北大核心 2024年第3期267-274,共8页
以水玻璃、矿渣粉为材料,基于逆Leidenfrost效应制备了多孔地聚合物微球,研究了其孔结构及pH缓冲性能.结果表明:改变水玻璃掺量和水固比可以调控多孔地聚合物微球的孔结构和pH缓冲性能;当水固比为1.0、水玻璃掺量由4%增大至8%时,微球的... 以水玻璃、矿渣粉为材料,基于逆Leidenfrost效应制备了多孔地聚合物微球,研究了其孔结构及pH缓冲性能.结果表明:改变水玻璃掺量和水固比可以调控多孔地聚合物微球的孔结构和pH缓冲性能;当水固比为1.0、水玻璃掺量由4%增大至8%时,微球的孔隙率、中位孔径和孔比表面积均减小,pH值波动范围为1.50~1.90;当水玻璃掺量为4%、水固比由1.0增大至1.2时,微球的孔隙率、中位孔径和孔比表面积均增大,pH值波动范围超过2.00;与双氧水直接发气法制备的多孔地聚合物相比,基于逆Leidenfrost效应制备的多孔地聚合物具有更好的pH缓冲性能和更高的OH-累积浸出量. 展开更多
关键词 逆Leidenfrost效应 矿渣 地聚合物 孔结构 ph缓冲性能
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NaCl胁迫下pH值和氮素形态对狗牙根生长及钠钾离子调控的影响
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作者 陈静波 李丹丹 +4 位作者 郝东利 宗俊勤 姚祥 刘建秀 郭海林 《植物资源与环境学报》 CAS CSCD 北大核心 2024年第2期30-40,共11页
以狗牙根〔Cynodon dactylon(Linn.)Pers.〕品种‘阳江’(‘Yangjiang’)为实验材料、2-(N-吗啡啉)乙磺酸(MES)为pH缓冲剂,采用水培法研究NaCl胁迫下pH值和氮素形态(铵态氮和硝态氮)对狗牙根生长和钠钾离子调控的影响。结果表明:处理1周... 以狗牙根〔Cynodon dactylon(Linn.)Pers.〕品种‘阳江’(‘Yangjiang’)为实验材料、2-(N-吗啡啉)乙磺酸(MES)为pH缓冲剂,采用水培法研究NaCl胁迫下pH值和氮素形态(铵态氮和硝态氮)对狗牙根生长和钠钾离子调控的影响。结果表明:处理1周后,若不添加MES,铵态氮处理组培养液的pH值下降到pH 4.0左右,而硝态氮处理组培养液的pH值则上升到pH 9.0左右;添加20 mmol·L^(-1)MES的铵态氮处理组培养液的pH值也下降到pH 4.0左右,而硝态氮处理组培养液的pH值则接近pH 7.0。与0 mmol·L^(-1)NaCl处理组相比,300 mmol·L^(-1)NaCl处理组狗牙根的枝条长度和枝条干质量显著(P<0.05)下降,而根长度、根干质量、根和叶中Na^(+)含量和Na^(+)/K^(+)比、钠钾选择性转运系数、叶Na^(+)和K^(+)的分泌量及分泌物Na^(+)/K^(+)比总体上显著升高。300 mmol·L^(-1)NaCl胁迫下,硝态氮处理组狗牙根的枝条长度、根长度、根干质量、根冠比、根中Na^(+)含量总体上显著高于铵态氮处理组,而叶中Na^(+)和K^(+)含量及Na^(+)/K^(+)比、叶Na^(+)和K^(+)的分泌量明显低于铵态氮处理组。300 mmol·L^(-1)NaCl胁迫下,20 mmol·L^(-1)MES处理组狗牙根的多数生长指标显著高于0 mmol·L^(-1)MES处理组,而根和叶中Na^(+)和K^(+)含量及Na^(+)/K^(+)比、钠钾选择性转运系数在0和20 mmol·L^(-1)MES处理组间的差异不显著。三因素方差分析结果表明:3个因子的单一和交互作用对多数生长指标、叶中Na^(+)含量和泌盐量相关指标的影响具有统计学意义。研究结果显示:硝态氮能缓解NaCl胁迫对狗牙根的伤害,而用MES缓冲根际酸碱环境对NaCl胁迫下狗牙根生长有一定的促进作用,因此,施用硝态氮或添加MES均有利于提高狗牙根的抗盐性。 展开更多
关键词 狗牙根 NACL胁迫 氮素形态 ph 离子调控 三因素方差分析
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基于二维相关红外光谱对pH值影响大豆分离蛋白二级结构含量的快速分析
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作者 刘畅 吴丹丹 +4 位作者 王宁 王睿莹 王立琦 刘峰 于殿宇 《食品科学》 EI CAS CSCD 北大核心 2024年第17期26-34,共9页
为满足不同种类食品对大豆分离蛋白(soybean protein isolate,SPI)不同功能性的需求,本研究利用红外光谱快速采集70组不同pH值处理后SPI的数据,探讨pH值变化对SPI结构含量的影响。使用均值中心化、多元散射校正、标准正态变量变换和归... 为满足不同种类食品对大豆分离蛋白(soybean protein isolate,SPI)不同功能性的需求,本研究利用红外光谱快速采集70组不同pH值处理后SPI的数据,探讨pH值变化对SPI结构含量的影响。使用均值中心化、多元散射校正、标准正态变量变换和归一化算法对红外光谱数据进行预处理,基于二维相关红外光谱提取特征波段,再利用偏最小二乘(partial least square,PLS)法和算术优化算法-随机森林(arithmetic optimization algorithm-random forests,AOA-RF)建立不同pH值条件下SPI结构及含量的预测模型。结果表明,经均值中心化和多元散射校正结合处理后,α-螺旋、β-折叠、β-转角和无规卷曲模型的相对标准偏差分别为1.29%、1.60%、1.37%、7.28%,两者结合对光谱数据的预处理效果最佳。预测α-螺旋和β-折叠含量最优模型为AOA-RF(特征波段),校正集决定系数为0.9350和0.9266,预测集决定系数为0.8568和0.8701;预测β-转角和无规卷曲含量最优模型为PLS(特征波段),校正集决定系数为0.9154和0.8817,预测集决定系数为0.8913和0.7843。本研究结果可为工业生产过程中产品质量快速检测和工艺条件控制提供理论支撑。 展开更多
关键词 二维相关红外光谱 大豆分离蛋白 二级结构 ph值变化 预测模型 快速分析
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超声辅助pH值偏移处理对大豆亲脂蛋白结构和功能性质的影响及其相关性分析
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作者 王帅 钟明明 +3 位作者 王震霄 王英 康梦雪 齐宝坤 《食品科学》 EI CAS CSCD 北大核心 2024年第16期169-176,共8页
为探究超声辅助pH值偏移对大豆亲脂蛋白(soybean lipophilic proteins,SLP)结构和功能性的影响,将分离提取的SLP在超声(240 W、20 min)及极端pH值(pH 1或12)条件下进行改性。采用十二烷基硫酸钠-聚丙烯酰胺凝胶电泳、游离巯基含量、傅... 为探究超声辅助pH值偏移对大豆亲脂蛋白(soybean lipophilic proteins,SLP)结构和功能性的影响,将分离提取的SLP在超声(240 W、20 min)及极端pH值(pH 1或12)条件下进行改性。采用十二烷基硫酸钠-聚丙烯酰胺凝胶电泳、游离巯基含量、傅里叶变换红外光谱、荧光光谱等对不同处理的SLP一级、二级、三级结构进行表征,并对SLP功能性质进行分析。结果表明:超声辅助pH 12偏移处理下SLP结构-功能性改变最大,平均粒径由5245.33 nm降低至447.13 nm,ζ-电位值由-5.95 mV下降至-18.53 mV,游离巯基含量下降,α-螺旋相对含量增加,荧光光谱发生蓝移,荧光强度降低;同时溶解度由9.84%上升至92.04%,乳化性、起泡性提高。因此超声和pH值偏移处理对SLP结构性质和功能性质具有协同作用,且结构和功能性质相关性较密切。 展开更多
关键词 大豆亲脂蛋白 超声辅助ph值偏移 结构性质 功能性质
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