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Research Progress of Detection Methods for Microplastics
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作者 Peng WAN Zhen ZHAO +3 位作者 Guoyan WEN Yunshuang FU Cuizhi LI Xiaoli WU 《Asian Agricultural Research》 2024年第3期29-32,共4页
Microplastics are plastic particles or fibers with a diameter of less than 5 mm,and they widely exist in the environment and pose potential risks to the ecosystem and human health.Microplastics detection can provide b... Microplastics are plastic particles or fibers with a diameter of less than 5 mm,and they widely exist in the environment and pose potential risks to the ecosystem and human health.Microplastics detection can provide basic data for formulating effective environmental protection strategies.In this paper,the physical,chemical and biological detection methods of microplastics are reviewed,and the advantages and disadvantages of different methods are analyzed.The problems and challenges encountered in microplastics detection are analyzed,and the future research is discussed. 展开更多
关键词 Microplastics DETECTION method research PROGRESS
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Research into Applicability of Wöhler Curve Method for Low-Cycle Fatigue of Metallic Materials
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作者 Xiangqiao Yan 《Journal of Harbin Institute of Technology(New Series)》 CAS 2024年第2期22-37,共16页
Recently,a description on a practicability of the Wöhler Curve Method for low-cycle fatigue of metals was given by the author.By the description and the low cycle fatigue test data of 16 MnR steel,it is important... Recently,a description on a practicability of the Wöhler Curve Method for low-cycle fatigue of metals was given by the author.By the description and the low cycle fatigue test data of 16 MnR steel,it is important to show that,for low cycle fatigue of metals,such a way that a stress-based intensity parameter calculated by the linear-elastic analysis is taken to be a stress intensity parameter,S,to establish a relationship between the stress intensity parameter,S,and the fatigue life,N,is practicable.In this paper,many metallic materials from the literature are given to show that the Wöhler Curve Method is well suitable for low-cycle fatigue analysis of metals. 展开更多
关键词 low cycle fatigue Wöhler curve method coffin-manson curve method METALS
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Research on the Generation Mechanism and Suppression Method of Aerodynamic Noise in Expansion Cavity Based on Hybrid Method
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作者 Haitao Liu Jiaming Wang +2 位作者 Xiuliang Zhang Yanji Jiang Qian Xiao 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第6期2747-2772,共26页
The expansion chamber serves as the primary silencing structure within the exhaust pipeline.However,it can also act as a sound-emitting structure when subjected to airflow.This article presents a hybrid method for num... The expansion chamber serves as the primary silencing structure within the exhaust pipeline.However,it can also act as a sound-emitting structure when subjected to airflow.This article presents a hybrid method for numerically simulating and analyzing the unsteady flow and aerodynamic noise in an expansion chamber under the influence of airflow.A fluid simulation model is established,utilizing the Large Eddy Simulation(LES)method to calculate the unsteady flow within the expansion chamber.The simulation results effectively capture the development and changes of the unsteady flow and vorticity inside the cavity,exhibiting a high level of consistency with experimental observations.To calculate the aerodynamic noise sources within the cavity,the flow field results are integrated using the method of integral interpolation and inserted into the acoustic grid.The acoustic analogy method is then employed to determine the aerodynamic noise sources.An acoustic simulation model is established,and the flow noise source is imported into the sound field grid to calculate the sound pressure at the far-field response point.The calculated sound pressure levels and resonance frequencies show good agreement with the experimental results.To address the issue of airflow regeneration noise within the cavity,perforated tubes are selected as a means of noise suppression.An experimental platformfor airflow regeneration noise is constructed,and experimental samples are processed to analyze and verify the noise suppression effect of perforated tube expansion cavities under different airflow velocities.The research findings indicate that the perforated tube expansion cavity can effectively suppress low-frequency aerodynamic noise within the cavity by impeding the formation of strong shear layers.Moreover,the semi-perforated tube expansion cavity demonstrates the most effective suppression of aerodynamic noise. 展开更多
关键词 Expansion cavity aerodynamic noise numerical simulation hybrid method perforated tube
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Research and Application of Bedside Rhetorical Teaching Method in Teaching Nursing Interns
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作者 Rui Cao 《Journal of Contemporary Educational Research》 2024年第4期226-229,共4页
Objective:To observe and analyze the application of the bedside rhetorical teaching method in teaching nursing interns.Methods:A total of 64 nursing interns in the gastroenterology department of our hospital from July... Objective:To observe and analyze the application of the bedside rhetorical teaching method in teaching nursing interns.Methods:A total of 64 nursing interns in the gastroenterology department of our hospital from July 2022 to May 2023 were randomly divided into two groups,32 cases in the control group and 32 cases in the intervention group.The control group was given conventional teaching methods,and the intervention group was given the bedside rhetorical teaching method on the basis of the conventional teaching.The differences in the methods of teaching between the two groups were compared after the end of the internship,and there was a statistically significant difference with P<0.05.Results:The scores of the interns in the intervention group were significantly better than those of the control group in theoretical knowledge,communication skills,and case analysis items(P<0.05).Conclusion:The bedside rhetorical teaching method transforms classroom education into bedside teaching,which enables the interns to apply the theoretical knowledge to clinical practice,and has a higher improvement in the three aspects of disease knowledge,communication skills,and case analysis,cultivates the interns’comprehensive clinical skills,and lays a good foundation for the future entry into the nursing field. 展开更多
关键词 Bedside rhetorical teaching method Nursing interns teaching Application research
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Research on Regulation Method of Energy Storage System Based on Multi-Stage Robust Optimization
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作者 Zaihe Yang Shuling Wang +3 位作者 Runhang Zhu Jiao Cui Ji Su Liling Chen 《Energy Engineering》 EI 2024年第3期807-820,共14页
To address the scheduling problem involving energy storage systems and uncertain energy,we propose a method based on multi-stage robust optimization.This approach aims to regulate the energy storage system by using a ... To address the scheduling problem involving energy storage systems and uncertain energy,we propose a method based on multi-stage robust optimization.This approach aims to regulate the energy storage system by using a multi-stage robust optimal control method,which helps overcome the limitations of traditional methods in terms of time scale.The goal is to effectively utilize the energy storage power station system to address issues caused by unpredictable variations in environmental energy and fluctuating load throughout the day.To achieve this,a mathematical model is constructed to represent uncertain energy sources such as photovoltaic and wind power.The generalized Benders Decomposition method is then employed to solve the multi-stage objective optimization problem.By decomposing the problem into a series of sub-objectives,the system scale is effectively reduced,and the algorithm’s convergence ability is improved.Compared with other algorithms,the multi-stage robust optimization model has better economy and convergence ability and can be used to guide the power dispatching of uncertain energy and energy storage systems. 展开更多
关键词 Multi-stage robust optimization energy storage system regulation methods output uncertainty
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Research on Sleeve Grouting Density Detection Based on the Impact Echo Method
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作者 Pu Zhang Yingjun Li +5 位作者 Xinyu Zhu Shizhan Xu Pinwu Guan Wei Liu Yanwei Guo Haibo Wang 《Structural Durability & Health Monitoring》 EI 2024年第2期143-159,共17页
Grouting defects are an inherent challenge in construction practices,exerting a considerable impact on the operational structural integrity of connections.This investigation employed the impact-echo technique for the ... Grouting defects are an inherent challenge in construction practices,exerting a considerable impact on the operational structural integrity of connections.This investigation employed the impact-echo technique for the detection of grouting anomalies within connections,enhancing its precision through the integration of wavelet packet energy principles for damage identification purposes.A series of grouting completeness assessments were meticulously conducted,taking into account variables such as the divergent material properties of the sleeves and the configuration of adjacent reinforcement.The findings revealed that:(i)the energy distribution for the highstrength concrete cohort predominantly occupied the frequency bands 42,44,45,and 47,whereas for other groups,it was concentrated within the 37 to 40 frequency band;(ii)the delineation of empty sleeves was effectively discernible by examining the wavelet packet energy ratios across the spectrum of frequencies,albeit distinguishing between sleeves with 50%and full grouting density proved challenging;and(iii)the wavelet packet energy analysis yielded variable detection outcomes contingent on the material attributes of the sleeves,demonstrating heightened sensitivity when applied to ultrahigh-performance concrete matrices and GFRP-reinforced steel bars. 展开更多
关键词 Prefabricated building steel grouting sleeve impact echo method wavelet packet energy grouted defect
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Research Progress in Detection of Explosives by Chemical Colorimetric Method
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作者 Lixiu He Yuefei Hu Zhiqiao Lv 《Expert Review of Chinese Chemical》 2024年第1期1-4,共4页
This article reviews the current application status and research progress of colorimetric detection methods based on chemical colorimetry in the detection of explosives.It mainly introduced colorimetric sensors,colori... This article reviews the current application status and research progress of colorimetric detection methods based on chemical colorimetry in the detection of explosives.It mainly introduced colorimetric sensors,colorimetric sensor arrays,and chemical colorimetric sensors based on novel material substrates.The application prospect of chemical colorimetric method in the field of explosives detection was prospected. 展开更多
关键词 chemical colorimetry explosives research progress
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Evaluation of the Effect of Assessment Method Reform in “Nursing Research” Course
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作者 Yunling Li Dandan Hu 《Journal of Contemporary Educational Research》 2024年第3期7-12,共6页
Objective:This paper aims to evaluate the implementation effect of the diversified course assessment method reform.Methods:A diversified assessment method was implemented for 196 undergraduate nursing students.Student... Objective:This paper aims to evaluate the implementation effect of the diversified course assessment method reform.Methods:A diversified assessment method was implemented for 196 undergraduate nursing students.Students’mastery of key knowledge in“Nursing Research”was assessed through group reports on topic selection and literature retrieval,as well as the proposition level of the final examination.Results:81.6%of the students agreed with the course assessment method,and 97.9%believed studying“Nursing Research”would be helpful for future scientific research applications.Conclusion:Diversified assessment methods can help improve undergraduate nursing students’scientific research skills and comprehensive quality. 展开更多
关键词 Nursing research Proposition assessment Undergraduate nursing students Topic selection Literature retrieval
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Research on Value Evaluation Method of Investment Project Based on Fuzzy Composite Real Options
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作者 Huanyu Li 《Economics World》 2024年第1期24-34,共11页
Venture capital investments are characterized by high input,high yield,and high risk.Due to the complexity of the market environment,stage-by-stage investment is becoming increasingly important.Traditional evaluation ... Venture capital investments are characterized by high input,high yield,and high risk.Due to the complexity of the market environment,stage-by-stage investment is becoming increasingly important.Traditional evaluation methods like comparison,proportion,maturity,internal rate of return,scenario analysis,decision trees,and net present value cannot fully consider the uncertainty and stage characteristics of the project.The fuzzy real options method addresses this by combining real option theory,fuzzy number theory,and composite option theory to provide a more accurate and objective evaluation of Public-Private Partnership(PPP)projects.It effectively considers the interaction of options and the ambiguity of project parameters,making it a valuable tool for project evaluation in the context of venture capital investment. 展开更多
关键词 real option fuzzy method Geske composite option
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Research on Teaching Methods of Flight Control Principles
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作者 Dongying Li 《Journal of Electronic Research and Application》 2024年第3期155-160,共6页
With the rapid development of China’s civil aviation industry,the teaching method of operating knowledge of flight principles has changed greatly,which creates a good implementation environment to improve the safety ... With the rapid development of China’s civil aviation industry,the teaching method of operating knowledge of flight principles has changed greatly,which creates a good implementation environment to improve the safety of civil aviation in our country.At present,the main training content of air route transport pilots in China is basic aviation theory,initial flight training,airline modification,etc.The principles of flight control are an important part of basic aviation theoretical knowledge training,which will involve a large number of flight technology training content,instructors will also be based on the pilot type.Teaching flight control theory and practical knowledge requires relatively high theoretical learning ability of students,and the learning effect of this part of theoretical knowledge will directly affect the quality of subsequent learning,but also directly affect the effectiveness of flight training.This paper focuses on the analysis of the basic concepts of flight control,studies the existing problems in the teaching of flight control principles,summarizes the teaching measures of flight control principles,aiming to provide a reference to teaching personnel. 展开更多
关键词 Flight control principle knowledge Virtual simulation Teaching method
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Discussion on Professor Ba Jigemude's Research Methods of the History of Mongolian Medicine
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作者 Aruna Alima Baolong 《Medicinal Plant》 CAS 2023年第1期96-99,共4页
The research methods of the history of Mongolian medicine refer to the general and special methods used in the understanding and research of the history of Mongolian medicine,as well as the methods of expression and c... The research methods of the history of Mongolian medicine refer to the general and special methods used in the understanding and research of the history of Mongolian medicine,as well as the methods of expression and compilation of the research achievements of the history of Mongolian medicine.There are not only analysis and generalization,abstractness and concreteness,deduction and induction,historical and logical methods,but also traditional philology methods such as textual research,exegesis and collation,as well as new methods such as field investigation method,empirical method,measurement method,comparison method,and oral account method.In the actual research process,a variety of methods are often used comprehensively.This paper mainly discusses the methods used by Professor Ba Jigemude in the study of the history of Mongolian medicine,and uses specific cases to analyze and summarize the formation and development of the history of ancient traditional medicine. 展开更多
关键词 Mongolian medicine research methods of medical history Ba Jigemude
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Synoptic review on existing and potential sources for bias in dental research methodology with methods on their prevention and remedies
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作者 Amit Arvind Agrawal Nilima Prakash +3 位作者 Mohammad Almagbol Mohammed Alobaid Abdullah Alqarni Hammam Altamni 《World Journal of Methodology》 2023年第5期426-438,共13页
The results of years of dental study serve as the foundation for the practise of medicine and,for that matter,dentistry.Doctors may have their own preferences for techniques and materials,but whether directly or indir... The results of years of dental study serve as the foundation for the practise of medicine and,for that matter,dentistry.Doctors may have their own preferences for techniques and materials,but whether directly or indirectly,their decisions are influenced by systematic reviews and meta-analyses.However,due to poorly conducted or presented research,this very basic foundation may not be reliable.Bias in research is one of several factors that might make study results or research itself unreliable.Bias can be introduced into research at many stages,deliberately or unknowingly.Bias can appear at any point during the research process,even before the study itself begins.There are many biases in research,but some of them are more relevant to dentistry research than others.Because it is said that“eyes see what the mind knows”,it is essential to have a complete understanding of the different types of bias,how and when they get entrenched,and what steps may be taken to prevent or lessen them if they do occur.This comprehensive summary of bias in dentistry research is provided by this synoptic review.The goal is to identify gaps and measures that have been taken-or that should have been taken-by providing both descriptive and evaluative summaries,as well as examples from the literature,when needed. 展开更多
关键词 Dental research Bias(epidemiology) research methodology research design Epidemiologic methods
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Research and Application of Log Defect Detection and Visualization System Based on Dry Coupling Ultrasonic Method
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作者 Yongning Yuan Dong Zhang +4 位作者 Usama Sayed Hao Zhu Jun Wang Xiaojun Yang Zheng Wang 《Journal of Renewable Materials》 EI 2023年第11期3917-3932,共16页
In order to optimize the wood internal quality detection and evaluation system and improve the comprehensive utilization rate of wood,this paper invented a set of log internal defect detection and visualization system... In order to optimize the wood internal quality detection and evaluation system and improve the comprehensive utilization rate of wood,this paper invented a set of log internal defect detection and visualization system by using the ultrasonic dry coupling agent method.The detection and visualization analysis of internal log defects were realized through log specimen test.The main conclusions show that the accuracy,reliability and practicability of the system for detecting the internal defects of log specimens have been effectively verified.The system can make the edge of the detected image smooth by interpolation algorithm,and the edge detection algorithm can be used to detect and reflect the location of internal defects of logs accurately.The content mentioned above has good application value for meeting the requirement of increasing demand for wood resources and improving the automation level of wood nondestructive testing instruments. 展开更多
关键词 Ultrasonic method log defect detection visualization system dry coupling B-scan pulse transmission method bilinear image interpolation algorithm edge detection algorithm
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Drilling-based measuring method for the c-φ parameter of rock and its field application 被引量:1
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作者 Bei Jiang Fenglin Ma +5 位作者 Qi Wang Hongke Gao Dahu Zhai Yusong Deng Chuanjie Xu Liangdi Yao 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2024年第1期65-76,共12页
The technology of drilling tests makes it possible to obtain the strength parameter of rock accurately in situ. In this paper, a new rock cutting analysis model that considers the influence of the rock crushing zone(R... The technology of drilling tests makes it possible to obtain the strength parameter of rock accurately in situ. In this paper, a new rock cutting analysis model that considers the influence of the rock crushing zone(RCZ) is built. The formula for an ultimate cutting force is established based on the limit equilibrium principle. The relationship between digital drilling parameters(DDP) and the c-φ parameter(DDP-cφ formula, where c refers to the cohesion and φ refers to the internal friction angle) is derived, and the response of drilling parameters and cutting ratio to the strength parameters is analyzed. The drillingbased measuring method for the c-φ parameter of rock is constructed. The laboratory verification test is then completed, and the difference in results between the drilling test and the compression test is less than 6%. On this basis, in-situ rock drilling tests in a traffic tunnel and a coal mine roadway are carried out, and the strength parameters of the surrounding rock are effectively tested. The average difference ratio of the results is less than 11%, which verifies the effectiveness of the proposed method for obtaining the strength parameters based on digital drilling. This study provides methodological support for field testing of rock strength parameters. 展开更多
关键词 Digital drilling Rock crushing zone c-u parameter Measurement method Field application
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Research on Freezing of Gait Recognition Method Based on Variational Mode Decomposition
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作者 Shoutao Li Ruyi Qu +1 位作者 Yu Zhang Dingli Yu 《Intelligent Automation & Soft Computing》 SCIE 2023年第9期2809-2823,共15页
Freezing of Gait(FOG)is the most common and disabling gait disorder in patients with Parkinson’s Disease(PD),which seriously affects the life quality and social function of patients.This paper proposes a FOG recognit... Freezing of Gait(FOG)is the most common and disabling gait disorder in patients with Parkinson’s Disease(PD),which seriously affects the life quality and social function of patients.This paper proposes a FOG recognition method based on the Variational Mode Decomposition(VMD).Firstly,VMD instead of the traditional time-frequency analysis method to complete adaptive decomposition to the FOG signal.Secondly,to improve the accuracy and speed of the recognition algorithm,use the CART model as the base classifier and perform the feature dimension reduction.Then use the RUSBoost ensemble algorithm to solve the problem of unbalanced sample size and considerable limitations of a single classifier.Finally,the hyperparam-eters of the ensemble classifier are optimized by Bayesian optimization,and the experiment proves that the RUSBoost algorithm can complete the gait recognition task well.Compared with the Adaboost,Tomeklinks-Adaboost and ROS-Adaboost ensemble algorithms,the RUSBoost ensemble algorithm can complete the FOG recognition task more efficiently.When the maximum number of splits is 1023,and the number of base classifiers is 100,the performance of the RUSBoost ensemble algorithm can reach the best.The accuracy of the time recognition algorithm was 87.8%,the sensitivity was 89.7%,and the specificity was 87.5%. 展开更多
关键词 FOG VMD RUSBoost Bayesian optimization method
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Application of evidence-based medicine methods in integrative oncology research
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作者 Jianping Liu Sijia Zhu Nicola Robinson 《Journal of Traditional Chinese Medical Sciences》 CAS 2023年第2期129-132,共4页
To present the advances of evidence-based medicine and clinical research methodology in integrative oncology,we conducted a literature review of real-world studies of traditional Chinese medicine(TCM)in cancer care an... To present the advances of evidence-based medicine and clinical research methodology in integrative oncology,we conducted a literature review of real-world studies of traditional Chinese medicine(TCM)in cancer care and summarized the available evidence.Pragmatic randomized controlled trials(pRCTs)and clinical registry studies are becoming more popular as they could compensate for the limitations of RCTs.Many RCTs of TCM for cancer treatment as well as systematic reviews have been published.The most investigated therapies are based on acupuncture,Chinese herbal compounds,and Chinese patent medicines.Acupuncture has a significant advantage in relieving cancer-related symptoms.Published studies focus more on improving clinical symptoms and laboratory indicators.However,the patient's quality of life deserves more attention. 展开更多
关键词 Evidence-based medicine Integrative oncology Traditional Chinese medicine research design Pragmatic clinical trial REGISTRIES
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A comparison study on structure-function relationship of polysaccharides obtained from sea buckthorn berries using different methods:antioxidant and bile acid-binding capacity 被引量:1
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作者 Qiaoyun Li Zuman Dou +5 位作者 Qingfei Duan Chun Chen Ruihai Liu Yueming Jiang Bao Yang Xiong Fu 《Food Science and Human Wellness》 SCIE CSCD 2024年第1期494-505,共12页
In this study,the structural characters,antioxidant activities and bile acid-binding ability of sea buckthorn polysaccharides(HRPs)obtained by the commonly used hot water(HRP-W),pressurized hot water(HRP-H),ultrasonic... In this study,the structural characters,antioxidant activities and bile acid-binding ability of sea buckthorn polysaccharides(HRPs)obtained by the commonly used hot water(HRP-W),pressurized hot water(HRP-H),ultrasonic(HRP-U),acid(HRP-C)and alkali(HRP-A)assisted extraction methods were investigated.The results demonstrated that extraction methods had significant effects on extraction yield,monosaccharide composition,molecular weight,particle size,triple-helical structure,and surface morphology of HRPs except for the major linkage bands.Thermogravimetric analysis showed that HRP-U with filamentous reticular microstructure exhibited better thermal stability.The HRP-A with the lowest molecular weight and highest arabinose content possessed the best antioxidant activities.Moreover,the rheological analysis indicated that HRPs with higher galacturonic acid content and molecular weight showed higher viscosity and stronger crosslinking network(HRP-C,HRP-W and HRP-U),which exhibited stronger bile acid binding capacity.The present findings provide scientific evidence in the preparation technology of sea buckthorn polysaccharides with good antioxidant and bile acid binding capacity which are related to the structure affected by the extraction methods. 展开更多
关键词 Sea buckthorn Extraction method STRUCTURE Rheological properties Antioxidant activity Bile acid binding capacity
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Research Status of Water Quality Criteria and Standards and Analysis on the Transformation Methods
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作者 Cheng LI Yihong WU +1 位作者 Yang ZHAO Ruyu YUAN 《Meteorological and Environmental Research》 CAS 2023年第3期69-72,共4页
Under the vision of development for the new era,China has entered a stage of high-quality economic development and an important window period in which we have the conditions and ability to address the prominent issue ... Under the vision of development for the new era,China has entered a stage of high-quality economic development and an important window period in which we have the conditions and ability to address the prominent issue of economic development and ecological protection in a coordinated way.However,all kinds of environmental benchmark values in China are lacking and need to be constantly supplemented and improved.Therefore,exploring and putting forward a simple and efficient method for the transformation of environmental criteria into environmental standards is an important basis for the rapid establishment of relevant environmental criteria system and the effective promotion of the development of environmental standards system towards a scientific and reasonable direction.In this paper,the water environment is taken as the research object.By analyzing the research progress of environmental criteria and standards at home and abroad,and the foreign method of transforming environmental criteria into environmental standards,combined with the problems faced in the process of transforming environmental criteria into environmental standards in China,an effective method to transform China's environmental criteria into environmental standards is analyzed.After analysis and comparison,it is found that the pollution reduction accounting method could achieve their simple and efficient conversion.Under the premise of obtaining environmental criteria for certain pollutants,environmental criteria for certain pollutants could be obtained by distributing pollutants reduction costs,and accounting economic benefits after reaching standard,thus obtaining the environmental standard of this type of pollutant,which provides reference to determine the environmental standard limits of such pollutants. 展开更多
关键词 Water quality criteria Water quality standards research status Transformation mechanism
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Research trends in methods for controlling macro-micro motion platforms
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作者 Lufan Zhang Pengqi Zhang +1 位作者 Boshi Jiang Heng Yan 《Nanotechnology and Precision Engineering》 EI CAS CSCD 2023年第3期64-78,共15页
With ongoing economic,scientific,and technological developments,the electronic devices used in daily lives are developing toward precision and miniaturization,and so the demand for high-precision manufacturing machine... With ongoing economic,scientific,and technological developments,the electronic devices used in daily lives are developing toward precision and miniaturization,and so the demand for high-precision manufacturing machinery is expanding.The most important piece of equipment in modern high-precision manufacturing is the macro-micro motion platform(M3P),which offers high speed,precision,and efficiency and has macro-micro motion coupling characteristics due to its mechanical design and composition of its driving components.Therefore,the design of the control system is crucial for the overall precision of the platform;conventional proportional–integral–derivative control cannot meet the system requirements,and so M3Ps are the subject of a growing range of modern control strategies.This paper begins by describing the development history of M3Ps,followed by their platform structure and motion control system components,and then in-depth assessments of the macro,micro,and macro-micro control systems.In addition to examining the advantages and disadvantages of current macro-micro motion control,recent technological breakthroughs are noted.Finally,based on existing problems,future directions for M3P control systems are given,and the present conclusions offer guidelines for future work on M3Ps. 展开更多
关键词 Macro-micro motion platform Precision positioning Control method Piezoelectric driver Voice coil motor
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Research Progress of Noninvasive Diagnostic Methods for Nonalcoholic Steatohepatitis
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作者 Yishi JIA Changkai ZHOU Ci SONG 《Agricultural Biotechnology》 CAS 2023年第3期87-91,共5页
Distinguishing between nonalcoholic steatohepatitis(NASH) and advanced liver fibrosis is the key for clinical diagnosis of non-alcoholic fatty liver disease(NAFLD). Liver biopsy, which is widely used for diagnosis of ... Distinguishing between nonalcoholic steatohepatitis(NASH) and advanced liver fibrosis is the key for clinical diagnosis of non-alcoholic fatty liver disease(NAFLD). Liver biopsy, which is widely used for diagnosis of liver diseases at present, has many drawbacks, such as being invasive, expensive and unstable. This article compares and summarizes the commonly used non-invasive diagnostic methods, including their diagnostic parameters, advantages and disadvantages, in order to provide a useful reference for the diagnosis of NASH. 展开更多
关键词 Nonalcoholic steatohepatitis Liver fibrosis Non-invasive diagnostic methods Bio-markers
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