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An overview on observational instruments and measuring methods for dewfall 被引量:1
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作者 Qiang Zhang XiaoCui Hao +2 位作者 XiaoMei Wen Sheng Wang Jian Zeng 《Research in Cold and Arid Regions》 2011年第1期78-85,共8页
This paper systematically summarizes previous measuring methods and observational instruments for the magnitude of dewfall on land surface, analyzes the characteristics of common observational instruments for land sur... This paper systematically summarizes previous measuring methods and observational instruments for the magnitude of dewfall on land surface, analyzes the characteristics of common observational instruments for land surface dewfall, and describes several basic dewfall measurement methods. Moreover, the basic principles of these methods and instruments are interpreted, and their advantages, disadvantages, and applicability are analyzed. Recommendations for the further improvement of these observational instruments and the development of dewfall measuring methods are presented, and new technologies and scientific proposals for exploiting dewfall are elucidated. 展开更多
关键词 dewfall measuring methods observational instrument exploitation and utilization technology
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Drilling-based measuring method for the c-φ parameter of rock and its field application 被引量:3
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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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Measuring Herbage Mass by Non-Destructive Methods: A Review 被引量:1
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作者 J. E. Lopez-Diaz A. I. Roca-Fernaindez Gonzalez-Rodriguez 《Journal of Agricultural Science and Technology(A)》 2011年第3X期303-314,共12页
Accurate assessment of herbage mass (HM) in pasture is a key to budgeting forage in grazing systems worldwide. Different non-destructive techniques to measuring pasture yield are commented. The methods compared incl... Accurate assessment of herbage mass (HM) in pasture is a key to budgeting forage in grazing systems worldwide. Different non-destructive techniques to measuring pasture yield are commented. The methods compared include visual estimations, manual and electronic pasture meters and remote sensing. All methods are associated with a moderate to high error, showing that some indirect methods of yield estimation are appropriate under most appropriate because many factors as climate variations, soil certain conditions. In general terms, no method was found as the characteristics, plant phenology, pasture management and species composition must be taken into account to make local calibrations from a general model. Best results were found modifying general methods under local calibrations and under local conditions. In order to give farmers the best method to manage adequately their own grazing systems, researchers must select the most suitable technique considering the scale of operation, the desired accuracy and the resources available. 展开更多
关键词 Forage mass estimation methods pasture yield non-destructive measuring.
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Measuring methods for three kinds of polyhydroxyalkanoates from activated sludge by gas chromatography
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作者 陈玮 陈志强 +2 位作者 吕炳南 温沁雪 张运海 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2011年第5期113-118,共6页
Gas chromatography determination of polyhydroxyalkanoates has been common;however,the pretreatment steps are often complex,and gas chromatography operation conditions are not given in detail.In this study,gas chromato... Gas chromatography determination of polyhydroxyalkanoates has been common;however,the pretreatment steps are often complex,and gas chromatography operation conditions are not given in detail.In this study,gas chromatography is used for analyzing PHB,PHV and PH2MV,three majors of PHAs in activated sludge.The sample was centrifuged at a speed of 4000 r/min for the separation of floc and supernatant,freezen,and dried for 12 h in vacuum freezing drier;and then transferred to the fridge for freezing to ice and drying for 12 h in vacuum freezing drier;then chloroform and a simple composition digestion solution including methanol,sulfuric acid and benzoic acid was added;digested at 105 ℃ for 6 h;cooled to room temperature,the lower solution of the result can be used for analyzing.Samples were analyzed by gas chromatography with FID detector and auto sampler;the standard curve of standard material shows an excellent linear relationship with correlation coefficients larger than 0.99;the relative standard deviation (RSD) of sludge samples is less than 1%.The recovery rates of each sample are between 95%-105%.The GC analysis time of each PHA sample is shorter than 10 minutes. 展开更多
关键词 POLYHYDROXYALKANOATES activated sludge gas chromatography measuring method
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Comparing Two Methods for Measuring Soil Bulk Density and Moisture Content 被引量:1
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作者 Jalal D. Jabro William B. Stevens William M. Iversen 《Open Journal of Soil Science》 2020年第6期233-243,共11页
<span style="font-family:Verdana;">Soil bulk density and moisture content are dynamic properties that vary with changes in soil and field conditions and have many agricultural, hydrological and environ... <span style="font-family:Verdana;">Soil bulk density and moisture content are dynamic properties that vary with changes in soil and field conditions and have many agricultural, hydrological and environmental implications. The main objective of this study was to compare between a soil core sampling method (core) and the CPN MC-3 Elite<span style="white-space:nowrap;"><sup>TM</sup></span> nuclear gauge method (radiation) for measuring bulk density (<span style="white-space:nowrap;"><i><span style="font-family:Verdana;white-space:normal;"></span><span style="font-family:Verdana;white-space:normal;"><span style="white-space:nowrap;"><i>ρ<sub>B</sub></i></span></span></i></span>) and volumetric moisture content (<span style="white-space:nowrap;"><i><span style="font-family:Verdana;white-space:normal;"><span style="white-space:nowrap;"><i>θ<span style="font-size:10.9091px;">v</span></i></span></span></i></span>) in a clay loam soil. Soil <span style="white-space:nowrap;"><i><span style="font-family:Verdana;white-space:normal;"><span style="white-space:nowrap;"><i>ρ<sub>B</sub></i></span></span></i></span> and <span style="white-space:nowrap;"><i><span style="font-family:Verdana;white-space:normal;"></span><span style="font-family:Verdana;white-space:normal;"><span style="white-space:nowrap;"><i>θ<span style="font-size:10.9091px;">v</span></i></span></span></i></span> measurements were determined using the core and radiation methods at 0 - 10 and 10 - 20 cm soil depths. The mean values of soil <span style="white-space:nowrap;"><i><span style="font-family:Verdana;white-space:normal;"><span style="white-space:nowrap;"><i>ρ<sub>B</sub></i></span></span></i></span> obtained using the core method (1.454, 1.492 g<span style="color:#4F4F4F;font-family:" font-size:14px;white-space:normal;background-color:#f7f7f7;"="">·</span>cm<span style="white-space:nowrap;"><sup>&minus;3</sup></span>) were greater than those obtained using the radiation method (1.343, 1.476 g<span style="color:#4F4F4F;font-family:" font-size:14px;white-space:normal;background-color:#f7f7f7;"="">·</span>cm<span style="white-space:nowrap;"><sup>&minus;3</sup></span>) at the 0 - 10 and 10 - 20 cm depths, respectively. Mean <span style="white-space:nowrap;"><i><span style="font-family:Verdana;white-space:normal;"><span style="white-space:nowrap;"><i>ρ<sub>B</sub></i></span></span></i></span> and <span style="white-space:nowrap;"><i><span style="font-family:Verdana;white-space:normal;"><span style="white-space:nowrap;"><i>θ<span style="font-size:10.9091px;">v</span></i></span></span></i></span> values averaged across both depths (referred to as the 0 - 20 cm depth) measured by the core method were 4.47% and 22.74% greater, respectively, than those obtained by the radiation method. The coefficients of variation (CV) of soil <span style="white-space:nowrap;"><i><span style="font-family:Verdana;white-space:normal;"></span><span style="font-family:Verdana;white-space:normal;"><span style="white-space:nowrap;"><i>ρ<sub>B</sub></i></span></span></i></span> values measured by the core method were lower than the CV values of those measured by the radiation method at both depths;however, the CV’s of <span style="white-space:nowrap;"><i><span style="font-family:Verdana;white-space:normal;"><span style="white-space:nowrap;"><i>ρ<sub>B</sub></i></span></span></i></span> values for both methods were larger at the 0 - 10 cm depth than those measured at the 10 - 20 cm depth. Similarly, the CV values of soil <span style="white-space:nowrap;"><i><span style="font-family:Verdana;white-space:normal;"><span style="white-space:nowrap;"><i>θ<sub>v</sub></i></span></span></i></span> values measured by the core method were lower than the CV values of those measured by the radiation method at both depths. There were significant differences between two methods in terms of <span style="white-space:nowrap;"><i><span style="font-family:Verdana;white-space:normal;"><span style="white-space:nowrap;"><i>ρ<sub>B</sub></i></span></span></i></span> and <span style="white-space:nowrap;"><i><span style="font-family:Verdana;white-space:normal;"><span style="white-space:nowrap;"><i>θ<sub>v</sub></i></span></span></i></span>, with the core method generating greater values than the radiation method at the 0 - 20 cm depth. These discrepancies between the two methods could have resulted from soil compaction and soil disturbance caused by the core and radiation techniques, respectively, as well as by other sources of error. Nevertheless, the core sampling method is considered the most common one for measuring <span style="white-space:nowrap;"><i><span style="font-family:Verdana;white-space:normal;"><span style="white-space:nowrap;"><i>ρ<sub>B</sub></i></span></span></i></span> for many agricultural, hydrological and environmental studies in most soils.</span> 展开更多
关键词 SOIL Bulk Density Moisture Content Core Method Radiation Method
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Measuring the velocity of sand particles in an air/particle two-phase flow:A comparison of several commonly used methods 被引量:2
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作者 Zhibao Dong GuangQiang Qian WanYin Luo HongTaoWang 《Research in Cold and Arid Regions》 2010年第3期185-197,共13页
The velocity of blown sand particles is an important parameter in aeolian movement (a special case of gas particle two-phase flow) and has ever been a topic of interest. At present, several techniques have been appl... The velocity of blown sand particles is an important parameter in aeolian movement (a special case of gas particle two-phase flow) and has ever been a topic of interest. At present, several techniques have been applied in measuring velocity of the blown sand particles. This paper reviews the measurement results of several commonly used methods: photoelectric cell method, high-speed photographic method, Particle Dynamics Analyzer (PDA) method and Particle Image Velocimetry (PIV) method. Photoelectric cell method, high-speed photograph method and PDA method are useful in studying the velocity distribution of particles. PIV is a whole-flow-field technique and a useful tool to study the average velocity field in a target area. These methods got some similar results but considerable differences also exist. They have come to similar conclusions on the velocity distributions at a single height but direct measurement results with respect to the velocity distribution very close to the surface are still scarce except some PDA results. The magnitude of measured mean particle velocity differs greatly. The relationship obtained by different methods between mean particle velocity and wind velocity, particle size and possibly other influencing factors also differs considerably. Although several authors have proposed similar power functions to describe the variation with height of the mean particle velocity, the predicted results have wide differences. Each technique is based on some unique principles, and has its advantages and disad- vantages. To make full use of different techniques, a lot of work needs be done to validate them. Developing a reliable technique to measure the velocity of blown particles is still a necessary task in aeolian research. 展开更多
关键词 aeolian transport velocity of particles measurement techniques
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Measuring phosphatidic acid phosphohydrolase (EC 3.1.3.4) activity using two phosphomolybdate-based colorimetric methods 被引量:1
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作者 Abul H. J. Ullah Kandan Sethumadhavan Jay Shockey 《Advances in Biological Chemistry》 2012年第4期416-421,共6页
Phosphatidic acid phosphohydrolase (3-sn-phosphatidate phosphohydrolase, EC 3.1.3.4), also known as PAP, catalyzes the dephosphorylation of phosphatidic acid (PtdOH) to form diacylglycerol (DAG) and inorganic orthopho... Phosphatidic acid phosphohydrolase (3-sn-phosphatidate phosphohydrolase, EC 3.1.3.4), also known as PAP, catalyzes the dephosphorylation of phosphatidic acid (PtdOH) to form diacylglycerol (DAG) and inorganic orthophosphate. In eukaryotes, the PAP driven reaction is the committed step in the synthesis of triacylglycerol (TAG). Existing methods for measuring PAP activity rely on the use of radioactive PtdOH. These methods are costly and cumbersome. In this report, we describe a simple assay procedure to measure released inorganic orthophosphate, which is a coproduct of the PAP reaction. Each molecule of PtdOH would release one molecule of DAG and one molecule of inorganic orthophosphate (Pi) when subjected to enzymatic breakdown under optimal conditions. Given the published rates of in vitro PAP enzymatic activity from various sources, we proposed that colorimetric determination of released Pi is possible. With this view, we performed in vitro PAP activity assays using freshly isolated enzyme from bitter gourd, Momordica charantia, and measured the released Pi using two spectrophotometric methods. Both methods gave about 2.0 to 2.25 ηkat per mg of protein. Thus, it is now possible to perform PAP activity using a simple procedure that uses nonradioactive substrates, provided the sample is dialyzed extensively to lower the intrinsic concentration of free phosphate. The kinetics data presented in this study is comparable to that of other PAP enzymes reported elsewhere, which gives credence to the notion that non-radioactive methods can be used to perform PAP activity. 展开更多
关键词 Phosphatidic ACID PHOSPHOHYDROLASE FATTY ACID Metabolism Diacyl GLYCEROL Inorganic ORTHOPHOSPHATE Measurement
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The effect of the different labeling and red cell removed methods on measuring the CD34^+cells of the cord blood
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《中国输血杂志》 CAS CSCD 2001年第S1期415-,共1页
关键词 cells of the cord blood CD The effect of the different labeling and red cell removed methods on measuring the CD34
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Re-measuring International Short-term Capital Flow into China with Varying Methods
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作者 张明 《China Economist》 2011年第5期80-92,共13页
This paper.fi'rst conducts a systematic review of domestic and foreign scholars' approaches to predicting short-term capital flows, then employs a combination of both direct and indirect methods to carry out its ana... This paper.fi'rst conducts a systematic review of domestic and foreign scholars' approaches to predicting short-term capital flows, then employs a combination of both direct and indirect methods to carry out its analysis. Three kinds of indicators, both specific and general, are applied in both methods. Thorough consideration is given to short-term international capital inflow from trade, other current account items, capital account, and errors and omissions, as well as other channels through which short term capital might accrue to a nation's balance. Based on a comprehensive comparison of year-on-year data, this paper also estimates monthly data using a simplified, indirect calculation approach. Estimates show that, despite a degree of difference in results between methods, most estimates are highly consistent for a given period. Based on monthly estimates, we conclude that turbulence in international financial markets (i.e., the United States subprime mortgage crisis and the European sovereign debt crisis) has had a major impact on China 's short-term capital flow. 展开更多
关键词 short-term international capital flows direct method indirect method scale measurement
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Simulation on Calculation Accuracy of Three Methods for Live Line Measuring the Parameters of Transmission Lines with Mutual Inductance
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作者 Jianjun Su Ronghua Zhang +6 位作者 Demin Cui Yongqiang Chai Xiaobo Li Chengxue Zhang Peiyan Li Zhijian Hu Yingying Hu 《Energy and Power Engineering》 2013年第4期1435-1439,共5页
Live line measurement methods can reduce the loss of power outages and eliminate interference. There are three live line measurement methods including integral method, differential method and algebraic method. A simul... Live line measurement methods can reduce the loss of power outages and eliminate interference. There are three live line measurement methods including integral method, differential method and algebraic method. A simulation model of?two coupled parallel transmission lines spanning on the same towers is built in PSCAD and the calculation errors of these three methods are compared with different sampling frequencies by using of Matlab. The effect of harmonic on calculation is also involved. The simulation results indicate that harmonic has the least effect on the algebraic method which provides stable result and small error. 展开更多
关键词 Lines with Mutual INDUCTANCE Zero Sequence Parameters LIVE LINE Measurement ALGEBRAIC METHOD Differential METHOD INTEGRAL METHOD
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A Review on Sources,Extractions and Analysis Methods of a Sustainable Biomaterial:Tannins 被引量:2
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作者 Antonio Pizzi Marie-Pierre Laborie Zeki Candan 《Journal of Renewable Materials》 EI CAS 2024年第3期397-425,共29页
Condensed and hydrolysable tannins are non-toxic natural polyphenols that are a commercial commodity industrialized for tanning hides to obtain leather and for a growing number of other industrial applications mainly ... Condensed and hydrolysable tannins are non-toxic natural polyphenols that are a commercial commodity industrialized for tanning hides to obtain leather and for a growing number of other industrial applications mainly to substitute petroleum-based products.They are a definite class of sustainable materials of the forestry industry.They have been in operation for hundreds of years to manufacture leather and now for a growing number of applications in a variety of other industries,such as wood adhesives,metal coating,pharmaceutical/medical applications and several others.This review presents the main sources,either already or potentially commercial of this forestry by-materials,their industrial and laboratory extraction systems,their systems of analysis with their advantages and drawbacks,be these methods so simple to even appear primitive but nonetheless of proven effectiveness,or very modern and instrumental.It constitutes a basic but essential summary of what is necessary to know of these sustainable materials.In doing so,the review highlights some of the main challenges that remain to be addressed to deliver the quality and economics of tannin supply necessary to fulfill the industrial production requirements for some materials-based uses. 展开更多
关键词 TANNINS FLAVONOIDS SOURCES extraction methods analysis methods
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Definition,measuring methods and status of carbon information disclosure in Chinese enterprises
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作者 CHEN Hua WANG Hai-yan 《Ecological Economy》 2015年第4期393-400,共8页
From the perspective of carbon disclosure goal,the paper defined the detail types of contents about carbon information disclosure,then constructed the carbon information disclosure index,by using the indices to 2011 a... From the perspective of carbon disclosure goal,the paper defined the detail types of contents about carbon information disclosure,then constructed the carbon information disclosure index,by using the indices to 2011 annual report of A-share listed companies in Shanghai and Shenzhen Security Exchange,we found that Chinese enterprises' carbon disclosure scattered,industry structure quite different characteristics,quantity information and quality information asymmetry. 展开更多
关键词 CARBON information DISCLOSURE content DEFINITION measuring methods STATUS DESCRIPTION
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Multi-Aspect Value of Measuring Systems and Methods Based on the Results of Roundness Measurements
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作者 Miodrag Hadzistevic Imre Nemedi +2 位作者 Milenko Sekulic Martin Bosak Janko Hodolic 《Journal of Mechanics Engineering and Automation》 2012年第8期514-530,共17页
The increase of quality consciousness brings about the growth of significance of metrological systems. Besides the significance, the level of automatization, flexibility, accuracy, et al. have advanced. The modern mea... The increase of quality consciousness brings about the growth of significance of metrological systems. Besides the significance, the level of automatization, flexibility, accuracy, et al. have advanced. The modern measuring systems are constructed so that nearly all necessary dimensional characteristics can be measured with them. However, conventional measuring systems are provided for particular mode measurements. This research paper presents and compares several conventional and modem measuring systems and methods. The measured value is roundness, one of the basic shapes of cross section in mechanical engineering. This paper arises in search of answers for the question whether conventional measuring techniques and equipments are made redundant because of the modern ones. In what segments and in which criterion are modem methods preferable? 展开更多
关键词 measuring systems ROUNDNESS V-block method coordinate measuring machine (CMM) rotational datum method(RDM).
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IMPROVEMENT OF FLUORIMETRIC AND UV-VISIBLE SPECTROPHOTOMETRIC ASSAY METHODS FOR MEASURING NITRIC OXIDE AND/OR EDRF IN BLOOD
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作者 杨凡 刘朴 《Journal of Pharmaceutical Analysis》 CAS 1995年第2期203-203,共1页
The increasing importance of endothelium-derived relaxing factor(EDRF),which has now been identified as nitric oxide (NO),has been underscored by the eltlcidation of its role'in a growing number of normal and path... The increasing importance of endothelium-derived relaxing factor(EDRF),which has now been identified as nitric oxide (NO),has been underscored by the eltlcidation of its role'in a growing number of normal and pathophysiological processes. Therefore techniques for detection of nitric oxide should serve as useful tools in defining the role of nitric oxide to these processes.We have improved a simple, sensitive assay methods for determination of nitric oxide in blood, tissue, and other body fluids both by fluorometric and by ultraviolet-visible spectrophotometric measurements. Data obtained by floores cence and by UV-visible assay were correlated well (r=0. 9938, P<0. 0001 ).Linearity:0.1 ̄ 100μmol/L,r =0.9996,P<0.0001. The minimum detection limit were < 10pmol/L. Within-and between-run CVs were 2. 48%and 4. 62% (n = 10),respectively.Reference values for healthy adults(n=40) were(9.82 ± 1. 57) pmol/L. In conclusion:the methods is sensitive, specific,and precise. It is fairly rapid and simple to perform andrequires no pretreatment of sample, i. e., plasma and urine.The value can be obtained by fluorimeter and/or UV-visible spectrophotometer.The present method is sufficiently rapid and simple to make this a practical choice for many laboratories. 展开更多
关键词 nitric oxided endothelium-derived relaxing factor measurement fluorescence ultraviolet-visible SPECTROPHOTOMETRY
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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:5
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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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Deciphering gastric inflammation-induced tumorigenesis through multi-omics data and AI methods 被引量:1
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作者 Qian Zhang Mingran Yang +3 位作者 Peng Zhang Bowen Wu Xiaosen Wei Shao Li 《Cancer Biology & Medicine》 SCIE CAS CSCD 2024年第4期312-330,共19页
Gastric cancer(GC), the fifth most common cancer globally, remains the leading cause of cancer deaths worldwide. Inflammation-induced tumorigenesis is the predominant process in GC development;therefore, systematic re... Gastric cancer(GC), the fifth most common cancer globally, remains the leading cause of cancer deaths worldwide. Inflammation-induced tumorigenesis is the predominant process in GC development;therefore, systematic research in this area should improve understanding of the biological mechanisms that initiate GC development and promote cancer hallmarks. Here, we summarize biological knowledge regarding gastric inflammation-induced tumorigenesis, and characterize the multi-omics data and systems biology methods for investigating GC development. Of note, we highlight pioneering studies in multi-omics data and state-of-the-art network-based algorithms used for dissecting the features of gastric inflammation-induced tumorigenesis, and we propose translational applications in early GC warning biomarkers and precise treatment strategies. This review offers integrative insights for GC research, with the goal of paving the way to novel paradigms for GC precision oncology and prevention. 展开更多
关键词 Gastric cancer inflammation-induced tumorigenesis multi-omics artificial intelligence network-based methods
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Data-driven methods for predicting the representative temperature of bridge cable based on limited measured data
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作者 WANG Fen DAI Gong-lian +2 位作者 HE Chang-lin GE Hao RAO Hui-ming 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第9期3168-3186,共19页
Cable-stayed bridges have been widely used in high-speed railway infrastructure.The accurate determination of cable’s representative temperatures is vital during the intricate processes of design,construction,and mai... Cable-stayed bridges have been widely used in high-speed railway infrastructure.The accurate determination of cable’s representative temperatures is vital during the intricate processes of design,construction,and maintenance of cable-stayed bridges.However,the representative temperatures of stayed cables are not specified in the existing design codes.To address this issue,this study investigates the distribution of the cable temperature and determinates its representative temperature.First,an experimental investigation,spanning over a period of one year,was carried out near the bridge site to obtain the temperature data.According to the statistical analysis of the measured data,it reveals that the temperature distribution is generally uniform along the cable cross-section without significant temperature gradient.Then,based on the limited data,the Monte Carlo,the gradient boosted regression trees(GBRT),and univariate linear regression(ULR)methods are employed to predict the cable’s representative temperature throughout the service life.These methods effectively overcome the limitations of insufficient monitoring data and accurately predict the representative temperature of the cables.However,each method has its own advantages and limitations in terms of applicability and accuracy.A comprehensive evaluation of the performance of these methods is conducted,and practical recommendations are provided for their application.The proposed methods and representative temperatures provide a good basis for the operation and maintenance of in-service long-span cable-stayed bridges. 展开更多
关键词 cable-stayed bridges representative temperature gradient boosted regression trees(GBRT)method field test limited measured data
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Hybrid Strategy of Partitioned and Monolithic Methods for Solving Strongly Coupled Analysis of Inverse and Direct Piezoelectric and Circuit Coupling
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作者 Daisuke Ishihara Syunnosuke Nozaki +1 位作者 Tomoya Niho Naoto Takayama 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第8期1371-1386,共16页
The inverse and direct piezoelectric and circuit coupling are widely observed in advanced electro-mechanical systems such as piezoelectric energy harvesters.Existing strongly coupled analysis methods based on direct n... The inverse and direct piezoelectric and circuit coupling are widely observed in advanced electro-mechanical systems such as piezoelectric energy harvesters.Existing strongly coupled analysis methods based on direct numerical modeling for this phenomenon can be classified into partitioned or monolithic formulations.Each formulation has its advantages and disadvantages,and the choice depends on the characteristics of each coupled problem.This study proposes a new option:a coupled analysis strategy that combines the best features of the existing formulations,namely,the hybrid partitioned-monolithic method.The analysis of inverse piezoelectricity and the monolithic analysis of direct piezoelectric and circuit interaction are strongly coupled using a partitioned iterative hierarchical algorithm.In a typical benchmark problem of a piezoelectric energy harvester,this research compares the results from the proposed method to those from the conventional strongly coupled partitioned iterative method,discussing the accuracy,stability,and computational cost.The proposed hybrid concept is effective for coupled multi-physics problems,including various coupling conditions. 展开更多
关键词 Structure-piezoelectric-circuit interaction energy harvesting partitioned method monolithic method hybrid method
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The influences of canopy temperature measuring on the derived crop water stress index
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作者 WANG Hongxi LI Fei +4 位作者 SHEN Hongtao LI Mengyu YIN Gongchao FANG Qin SHAO Liwei 《中国生态农业学报(中英文)》 CAS CSCD 北大核心 2024年第9期1503-1519,共17页
Crop water stress index(CWSI)is widely used for efficient irrigation management.Precise canopy temperature(T_(c))measurement is necessary to derive a reliable CWSI.The objective of this research was to investigate the... Crop water stress index(CWSI)is widely used for efficient irrigation management.Precise canopy temperature(T_(c))measurement is necessary to derive a reliable CWSI.The objective of this research was to investigate the influences of atmospheric conditions,settled height,view angle of infrared thermography,and investigating time of temperature measuring on the performance of the CWSI.Three irrigation treatments were used to create different soil water conditions during the 2020-2021 and 2021-2022 winter wheat-growing seasons.The CWSI was calculated using the CWSI-E(an empirical approach)and CWSI-T(a theoretical approach)based on the T_(c).Weather conditions were recorded continuously throughout the experimental period.The results showed that atmospheric conditions influenced the estimation of the CWSI;when the vapor pressure deficit(VPD)was>2000 Pa,the estimated CWSI was related to soil water conditions.The height of the installed infrared thermograph influenced the T_(c)values,and the differences among the T_(c)values measured at height of 3,5,and 10 m was smaller in the afternoon than in the morning.However,the lens of the thermometer facing south recorded a higher T_(c)than those facing east or north,especially at a low height,indicating that the direction of the thermometer had a significant influence on T_(c).There was a large variation in CWSI derived at different times of the day,and the midday measurements(12:00-15:00)were the most reliable for estimating CWSI.Negative linear relationships were found between the transpiration rate and CWSI-E(R^(2)of 0.3646-0.5725)and CWSI-T(R^(2)of 0.5407-0.7213).The relations between fraction of available soil water(FASW)with CWSI-T was higher than that with CWSI-E,indicating CWSI-T was more accurate for predicting crop water status.In addition,The R^(2)between CWSI-T and FASW at 14:00 was higher than that at other times,indicating that 14:00 was the optimal time for using the CWSI for crop water status monitoring.Relative higher yield of winter wheat was obtained with average seasonal values of CWSI-E and CWSI-T around 0.23 and 0.25-0.26,respectively.The CWSI-E values were more easily influenced by meteorological factors and the timing of the measurements,and using the theoretical approach to derive the CWSI was recommended for precise irrigation water management. 展开更多
关键词 Canopy temperature measuring time measuring height and direction Crop water stress index
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Application of Digital Image Correlation and Geodetic Displacement Measuring Methods to Monitor Water Dam Behavior under Dynamic Load
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作者 Janina Zaczek-Peplinska Maria Elzbieta Kowalska +1 位作者 Krzysztof Malowany MarcinMalesa 《Journal of Civil Engineering and Architecture》 2015年第12期1496-1505,共10页
This paper presents experiment results of the measurement conducted at the Roznew Dam power plant. For a course of starting and operating of turbo-plants, downstream face of the dam was monitored in relation to its ev... This paper presents experiment results of the measurement conducted at the Roznew Dam power plant. For a course of starting and operating of turbo-plants, downstream face of the dam was monitored in relation to its eventual displacements on direction parallel to the construction axis. For the purpose of the experiment, geodetic measurement techniques and 2D DIC (digital image correlation) method (utilizing photographs of the object recorded with digital camera) were compared with regard to credibility, efficiency and accuracy. The vertical and horizontal displacements were monitored by tachometers measurements. The deformations in x-axis and y-axis on the wall surface was monitored by 2D DIC. It has been noticed that 2D DIC method is a surface method, continuous--not discreet. It allows for continuous observations of surface deformations, which is not possible in case of tachemetric measurements. Despite many advantages, the 2D DIC method lacks unambiguous evaluation of precision and relevance of designated displacements, which is rather significant for possibilities of utilization in technical control of large engineered objects. It should be also marked that the tachometric method is more reliable but is more laborious. Research of this type might comprise additional element for the assessment of the influence of dynamic loads, such as activating turbine water flow, onto the overall condition of the surveyed structure. 展开更多
关键词 Hydrotechnical structure structure dynamic load engineering object displacement geodetic displacement measurements.digital image correlation.
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