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An economical and flexible chip using surface-enhanced infrared absorption spectroscopy for pharmaceutical detection:Combining qualitative analysis and quantitative detection 被引量:1
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作者 Jikai Wang Pengfei Zeng +3 位作者 Haitao Xie Suisui He Xilin Xiao Cuiyun Yu 《Journal of Pharmaceutical Analysis》 2025年第2期474-476,共3页
Infrared(IR)spectroscopy,a technique within the realm of molecular vibrational spectroscopy,furnishes distinctive chemical signatures pivotal for both structural analysis and compound identification.A notable challeng... Infrared(IR)spectroscopy,a technique within the realm of molecular vibrational spectroscopy,furnishes distinctive chemical signatures pivotal for both structural analysis and compound identification.A notable challenge emerges from the misalignment between the mid-IR light wavelength range and molecular dimensions,culminating in a constrained absorption cross-section and diminished vibrational absorption coefficients(Supplementary data). 展开更多
关键词 pharmaceutical detection quantitative detection structural analysis surface enhanced infrared absorption spectroscopy qualitative analysis chemical signatures infrared spectroscopy molecular vibrational spectroscopyfurnishes
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Qualitative Evaluation of Academic Researchers in Computer Science:Practices and Reflections from CNRS
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作者 Pierre Senellart 《计算机教育》 2025年第12期36-41,共6页
The evaluation of academic researchers often relies on quantitative metrics,despite their limitations.This paper examines the qualitative assessment approach used by the French National Center for Scientific Research(... The evaluation of academic researchers often relies on quantitative metrics,despite their limitations.This paper examines the qualitative assessment approach used by the French National Center for Scientific Research(CNRS)in Computer Science(Section 6),as presented by a National Committee for Scientific Research(CoNRS)committee president.Rejecting bibliometrics like impact factors,CNRS emphasizes in-depth peer review of research quality,diverse outputs(e.g.,software and datasets),and field-specific considerations.The process,aligned with the San Francisco Declaration on Research Assessment(DORA),faces challenges in scalability and subjectivity,addressed through committee diversity and structured deliberation.This work provides insights for institutions seeking fairer,more holistic research evaluation frameworks. 展开更多
关键词 Research evaluation qualitative assessment CNRS DORA Computer science
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A quantitative evaluation method of laser treatment efficacy for pigmentary dermatosis based on image segmentation technology
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作者 Haopu Jian Qi Chen +3 位作者 Youjun Yu Cheng Wang Peiru Wang Xiuli Wang 《Journal of Innovative Optical Health Sciences》 2025年第4期89-99,共11页
A growing number of skin laser treatments have rapidly evolved and increased their role in the field of dermatology,laser treatment is considered to be used for a variety of pigmentary dermatosis as well as aesthetic ... A growing number of skin laser treatments have rapidly evolved and increased their role in the field of dermatology,laser treatment is considered to be used for a variety of pigmentary dermatosis as well as aesthetic problems.The standardized assessment of laser treatment efficacy is crucial for the interpretation and comparison of studies related to laser treatment of skin disorders.In this study,we propose an evaluation method to quantitatively assess laser treatment efficacy based on the image segmentation technology.A tattoo model of Sprague Dawley(SD)rats was established and treated by picosecond laser treatments at varying energy levels.Images of the tattoo models were captured before and after laser treatment,and feature extraction was conducted to quantify the tattooed area and pigment gradation.Subsequently,the clearance rate,which has been a standardized parameter,was calculated.The results indicate that the clearance rates obtained through this quantitative algorithm are comparable and exhibit smaller standard deviations compared with scale scores(4.59%versus 7.93%in the low-energy group,4.01%versus 9.05%in the medium-energy group,and 4.29%versus 10.23%in the high-energy group).This underscores the greater accuracy,objectivity,and reproducibility in assessing treatment responses.The quantitative evaluation of pigment removal holds promise for facilitating faster and more robust assessments in research and development.Additionally,it may enable the optimization of treatments tailored to individual patients,thereby contributing to more effective and personalized dermatological care. 展开更多
关键词 Pigmentary dermatosis picosecond laser image segmentation quantitative evaluation
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Research on Evaluation Scheme for Quantitative Sense from the Perspective of Core Competencies:Taking the Measurement Unit of the Sixth Unit in the First Volume of the Second Grade of the Beijing Normal University Edition as an Example
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作者 Jia Gu Yunxia He 《Journal of Contemporary Educational Research》 2025年第7期169-175,共7页
The implementation of core competencies clarifies social talent needs and guides math classroom evaluation.Lower-grade primary students,highly malleable,need targeted teacher guidance.Teaching evaluation should meet t... The implementation of core competencies clarifies social talent needs and guides math classroom evaluation.Lower-grade primary students,highly malleable,need targeted teacher guidance.Teaching evaluation should meet the talent demands of the times,focusing on core literacy and essential character development.From this perspective,primary math teachers should optimize evaluation,build a diversified system,help students grow in math,find their learning position,and advance confidently. 展开更多
关键词 Core competencies Lower primary school quantitative sense evaluation scheme
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Evaluation of the shear stability of aerobic granular sludge from a pilot-scale membrane bioreactor:Establishment of a quantitative method
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作者 Biao Yang Bingduo Wang +7 位作者 Liying Bin Weirui Chen Xinyi Chen Ping Li Shanglong Wen Shaosong Huang Zhiqi Zhang Bing Tang 《Journal of Environmental Sciences》 2025年第2期579-590,共12页
This work established a quantitative method to access the shear stability of aerobic granular sludge(AGS)and validated its feasibility by using the mature AGS from a pilot-scale(50 tons/day)membrane bioreactor(MBR)for... This work established a quantitative method to access the shear stability of aerobic granular sludge(AGS)and validated its feasibility by using the mature AGS from a pilot-scale(50 tons/day)membrane bioreactor(MBR)for treating real municipal wastewater.The results showed that the changing rate( S)of the peak area(S)of granule size distribution(GSD)exhibited an exponential relationship(R^(2)≥0.76)with the shear time(y=a−b·c^(x)),which was a suitable indicative index to reflect the shear stability of different AGS samples.The limiting granule size(LGS)was defined and proposed to characterize the equilibrium size for AGS after being sheared for a period of time,whose value in terms of Dv50 showed high correlation(R^(2)=0.92)with the parameter a.The free Ca^(2+)(28.44-34.21 mg/L)in the influent specifically interacted with polysaccharides(PS)in the granule’s extracellular polymeric substance(EPS)as a nucleation site,thereby inducing the formation of Ca precipitation to enhance its Young’s modulus,while Ca^(2+) primarily interacted with PS in soluble metabolic product(SMP)during the initial granulation process.Furthermore,the Young’s modulus significantly affected the parameter a related to shear stability(R^(2)=0.99).Since the parameter a was more closely related(R^(2)=1.00)to S than that of the parameter b or c,the excellent correlation(R^(2)=0.99)between the parameter a and the wet density further verified the feasibility of this method. 展开更多
关键词 Shear stability quantitative evaluation Aerobic granular sludge Membrane bioreactor Pilot-scale study Municipal wastewater
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Quantitative Evaluation of Gas Injection Contribution Using Fluid Inclusion Data:A Case Study of the Condensate Gas Reservoirs of the Eastern Shunbei Area in the Tarim Basin
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作者 Zicheng Cao Lu Yun +6 位作者 Hongwei Ping Haiying Li Feng Geng Jun Han Cheng Huang Xin Yang Honghan Chen 《Journal of Earth Science》 2025年第6期2819-2824,共6页
0 INTRODUCTION Gas injection refers to the natural gas charging into pre-existing oil reservoirs,which often leads to notable changes in gas-oil ratio(GOR),oil density,and phase states,depending on the pressure-temper... 0 INTRODUCTION Gas injection refers to the natural gas charging into pre-existing oil reservoirs,which often leads to notable changes in gas-oil ratio(GOR),oil density,and phase states,depending on the pressure-temperature condition of the reservoirs(Meulbroek et al.,1998;Blanc and Connan,1994;Evans et al.,1971). 展开更多
关键词 natural gas gas injection fluid inclusion pressure temperature condition eastern shunbei area tarim basin quantitative evaluation condensate gas reservoirs
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Qualitative and quantitative analysis of four different polarity fractions from Huang-Lian-Jie-Du-Decoction by HPLC-DAD-ESI-MS/MS and their related neuroprotective effects 被引量:6
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作者 杨阳 赵海誉 +4 位作者 王宏洁 宋建芳 杨健 司南 边宝林 《Journal of Chinese Pharmaceutical Sciences》 CAS CSCD 2013年第4期334-341,共8页
Huang-Lian-Jie-Du-Decoction (HLJDD) has been widely used for the treatment of Alzheimer's disease (AD) in clinic. However, the relationship between its chemical profile and neuroprotective bioactivity was not cle... Huang-Lian-Jie-Du-Decoction (HLJDD) has been widely used for the treatment of Alzheimer's disease (AD) in clinic. However, the relationship between its chemical profile and neuroprotective bioactivity was not clearly clarified yet. In present study, the water extract of HLJDD and subsequent three polarity fractions divided by different reagents were investigated. A total of 17 chromatographic peaks were confirmed by comparison with standards and their UV, MS spectra. Among them, 11 major compounds were determined by HPLC-DAD method with good linear regression relationship (r2, 0.9994-0.9999), precisions (inter-day precision RSD, 0.79%-1.07%; intra-day precision RSD, 1.59%-2.10%), repeatability (RSD, 1.66%-3.67%), stability (RSD, 1.26%-4.77%) and recovery (95.24%-105.41%, RSD, 0.29%-2.69%). Furthermore, PC12 cells and primary neurons cells were used for the neuroprotective effective assessment of aforementioned four samples from HLJDD. 3"he total aqueous extract and n-butanol extract of HLJDD presented more significant effects than the other two parts. According to their quality and quantity determination results, iridoids and alkaloids have a positive correlation with the neuroprotective effectiveness of HLJDD. 展开更多
关键词 Huang-Lian-Jie-Du-Decoction qualitative and quantitative analysis Neuroprotective effects
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Study on Quantitative Evaluation of Rural Tourist Resources in Xichang City
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作者 熊金银 《Journal of Landscape Research》 2010年第9期92-95,共4页
Quantitative evaluation was conducted on rural tourist resources in Xichang City by national standard resources grading method and analytic hierarchy process. It was concluded that rural tourist resources in Xichang C... Quantitative evaluation was conducted on rural tourist resources in Xichang City by national standard resources grading method and analytic hierarchy process. It was concluded that rural tourist resources in Xichang City were diversified in resources type and high in resources value and there were excellent rural tourist resources. The study provided a scientific and quantitative evaluation for reasonable development of rural tourism. 展开更多
关键词 RURAL TOURIST RESOURCES quantitative evaluation ANALYTIC HIERARCHY process National standard RESOURCES GRADING
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Qualitative and quantitative ATR-FTIR analysis and its application to coal char of different ranks 被引量:20
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作者 Andrew O.Odeh 《燃料化学学报》 EI CAS CSCD 北大核心 2015年第2期129-137,共9页
This paper analyzes the coal to char stages of char formation of six coals of different ranks by using Fourier transform infrared coupled w ith attenuated total reflectance(ATR-FTIR).The chars w ere obtained by coal p... This paper analyzes the coal to char stages of char formation of six coals of different ranks by using Fourier transform infrared coupled w ith attenuated total reflectance(ATR-FTIR).The chars w ere obtained by coal pyrolysis carried out at temperature range of 450~700℃.The data obtained show s the pragmatic disappearance of the aliphatic hydrogen content w ith increasing char formation temperature.Numerical evaluation of the spectra enabled the determination of aromaticity,fa.The aromaticity w as found to be betw een 0.66~0.79 for lignite,0.75~0.90 for sub-bituminous,0.84~1.00 for low volatile bituminous,0.83~1.00 for high volatile bituminous,0.94~1.00 for semi-anthracite,and 0.97~1.00 for anthracite respectively.With increasing rank of coal samples,spectra exhibit rising aromaticity and enhanced condensation of aromatic rings,w hereas the aliphatic chain lengths decrease. 展开更多
关键词 qualitative quantitative FT-IR coal char
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Qualitative and Quantitative Analysis of Alkaloids in Cortex Phellodendri by HPLC-ESI-MS/MS and HPLC-DAD 被引量:19
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作者 ZHU Shuang-lai DOU Sheng-shan +6 位作者 LIU Xin-ru LIU Run-hui ZHANG Wei-dong HUANG Hong-lin ZHANG Yi HU Yao-hua WANG Shu-ping 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2011年第1期38-44,共7页
A combined method of high performance liquid chromatograph-elecrtrospray-ionization mass spectrometer(HPLC-ESI-MS/MS) coupled with a photodiode array detector(HPLC-DAD) and principal component analysis(PCA) was ... A combined method of high performance liquid chromatograph-elecrtrospray-ionization mass spectrometer(HPLC-ESI-MS/MS) coupled with a photodiode array detector(HPLC-DAD) and principal component analysis(PCA) was applied to the qualitative and quantitative analyses of alkaloids in Cortex Phellodendri(CP) samples, and to the differentiation of two species of CP, Cortex Phellodendri Chinensis(CPC) and Cortex Phellodendri Amurensis(CPA). Twenty-two peaks appeared in the HPLC-MS base peak chromatogram of CP detected by the HPLC-ESI-MS/MS analysis, and the alkaloids were identified according to the MSn data, the known MS fragmentation rules and the literature data. Five alkaloids including berberine, palmatine, jatrorrhizine, phellodendrine and magnoflorine were simultaneously determinated by the HPLC-DAD. Berberine was the primary component in all CP samples, and the contents of berberine and palmatine were exploited to be two critical parameters for effective discrimination between the two species of CP. The average content of berberine in CPC(58.75 mg/g) was higher than that in CPA(9.16 mg/g), while the content of palmatine was less, only 0.25 mg/g in CPC and 4.19 mg/g in CPA. With the use of PCA, samples datasets were separated successfully into two different clusters corresponding to the two species, and berberine, pahnatine, phellodendrine and magnoflorine contribute most to the above mentioned calssifying . The proposed method oroved to be a useful tool in the aualitv control of Chinese herbal medicines. 展开更多
关键词 Cortex Phellodendri ALKALOID HPLC-ESI-MS/MS quantitative analysis qualitative analysis Principal component analysis
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Quantitative evaluation methods for waterflooded layers of conglomerate reservoir based on well logging data 被引量:22
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作者 Tan Fengqi Li Hongqi +2 位作者 Xu Changfu Li Qingyuan Peng Shouchang 《Petroleum Science》 SCIE CAS CSCD 2010年第4期485-493,共9页
The rapid changing near source, multi-stream depositional environment of conglomerate reservoirs leads to severe heterogeneity, complex lithology and physical properties, and large changes of oil layer resistivity. Qu... The rapid changing near source, multi-stream depositional environment of conglomerate reservoirs leads to severe heterogeneity, complex lithology and physical properties, and large changes of oil layer resistivity. Quantitative evaluation of water-flooded layers has become an important but difficult focus for secondary development of oilfields. In this paper, based on the analysis of current problems in quantitative evaluation of water-flooded layers, the Kexia Group conglomerate reservoir of the Sixth District in the Karamay Oilfield was studied. Eight types of conglomerate reservoir lithology were identified effectively by a data mining method combined with the data from sealed coring wells, and then a multi-parameter model for quantitative evaluation of the water-flooded layers of the main oil-bearing lithology was developed. Water production rate, oil saturation and oil productivity index were selected as the characteristic parameters for quantitative evaluation of water-flooded layers of conglomerate reservoirs. Finally, quantitative evaluation criteria and identification rules for water-flooded layers of main oil-bearing lithology formed by integration of the three characteristic parameters of water-flooded layer and undisturbed formation resistivity. This method has been used in evaluation of the water-flooded layers of a conglomerate reservoir in the Karamay Oilfield and achieved good results, improving the interpretation accuracy and compliance rate. It will provide technical support for avoiding perforation of high water-bearing layers and for adjustment of developmental programs. 展开更多
关键词 Water-flooded layer quantitative evaluation conglomerate reservoir lithology identification decision tree characteristic parameters
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Evaluation and Quantitative Inheritance of Several Drought-Relative Traits in Maize 被引量:11
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作者 FU Feng-ling FENG Zhi-lei GAO Shi-bing ZHOU Shu-feng LI Wan-chen 《Agricultural Sciences in China》 CAS CSCD 2008年第3期280-290,共11页
The authors evaluated 57 parental inbred lines of maize hybrids disseminated in Southwest China for drought tolerance under drought-stressed and well-watered conditions. Multiple regression analyses between drought to... The authors evaluated 57 parental inbred lines of maize hybrids disseminated in Southwest China for drought tolerance under drought-stressed and well-watered conditions. Multiple regression analyses between drought tolerant coefficients of the grain yield per plant and 15 morphological and physiological traits measured from a subset of 12 selected lines, identified traits 1 and 5, which were important for drought tolerance, at the seedling and reproductive stages respectively. Gene effects, combining abilities, and heritabilities of these traits were estimated using generation mean and diallel cross methods. Dominance effect was more important than additive effect for the plant height, anthesis-silking interval (ASI), root weight, and the grain yield per plant, whereas, they were about equal for the leaf emergence rate. The variances of special combining ability (SCA) were about double that of the general combining ability (GCA) for plant height, ASI and grain yield per plant, although they were about equal for leaf emergence rate and root weight. Narrow sense heritabilities of the five traits for the reproductive stage were not high (12.8-29.6%), although broad sense heritabilities for plant height, ASI, and grain yield were as high as 70-85%. A segregating population consisting of 183 F2 plants from the cross N87-1 (drought tolerant) × 9526 (susceptible), was genotyped at 103 SSR loci and the F2:4 families were evaluated under two water regimes. Twelve quantitative trait loci (QTLs) (two for plant height, five for ASI, four for root biomass, and one for grain yield) were identified, most of which had overdominant gene action. Some chromosomal regions, such as those linked to markers umcl051 (bin 4.08), umc2881 (bin 4.03), and phi034 (bin 7.02), had overlapping QTLs. 展开更多
关键词 MAIZE drought tolerance evaluation quantitative inheritance QTL
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Strategies on Sample Size Determination and Qualitative and Quantitative Traits Integration to Construct Core Collection of Rice (Oryza sativa) 被引量:6
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作者 LI Xiao-ling LU Yong-gen +2 位作者 LI Jin-quan XU Hai-ming Muhammad Qasim SHAHID 《Rice science》 SCIE 2011年第1期46-55,共10页
The development of a core collection could enhance the utilization of germplasm collections in crop improvement programs and simplify their management. Selection of an appropriate sampling strategy is an important pre... The development of a core collection could enhance the utilization of germplasm collections in crop improvement programs and simplify their management. Selection of an appropriate sampling strategy is an important prerequisite to construct a core collection with appropriate size in order to adequately represent the genetic spectrum and maximally capture the genetic diversity in available crop collections. The present study was initiated to construct nested core collections to determine the appropriate sample size to represent the genetic diversity of rice landrace collection based on 15 quantitative traits and 34 qualitative traits of 2 262 rice accessions. The results showed that 50-225 nested core collections, whose sampling rate was 2.2%-9.9%, were sufficient to maintain the maximum genetic diversity of the initial collections. Of these, 150 accessions (6.6%) could capture the maximal genetic diversity of the initial collection. Three data types, i.e. qualitative traits (QT1), quantitative traits (QT2) and integrated qualitative and quantitative traits (QTT), were compared for their efficiency in constructing core collections based on the weighted pair-group average method combined with stepwise clustering and preferred sampling on adjusted Euclidean distances. Every combining scheme constructed eight rice core collections (225, 200, 175, 150, 125, 100, 75 and 50). The results showed that the QTT data was the best in constructing a core collection as indicated by the genetic diversity of core collections. A core collection constructed only on the information of QT1 could not represent the initial collection effectively. QTT should be used together to construct a productive core collection. 展开更多
关键词 nested core collection sample size quantitative traits qualitative traits integrated qualitative and quantitative traits RICE
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Performances and Germplasm Evaluation of Quantitative Resistance to Soybean Mosaic Virus in Soybeans 被引量:16
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作者 ZHIHai-jian GAIJun-yi 《Agricultural Sciences in China》 CAS CSCD 2004年第4期247-253,共7页
A sample composed of 96 soybean accessions was evaluated for their diseased rate (I),diseased rank (S), latent period (LP) and rate of disease development (R) in order tostudy the quantitative resistance to soybean mo... A sample composed of 96 soybean accessions was evaluated for their diseased rate (I),diseased rank (S), latent period (LP) and rate of disease development (R) in order tostudy the quantitative resistance to soybean mosaic virus (SMV) in soybeans. The resultsshowed that the performances of the above four resistance components were significantlydifferent among accessions and that some of the accessions, such as Zhongzihuangdou,Peixian Tianedan, Youbian30 could be infected by four SMV strains, Sa, SC8, N1 and N3,but their I, S, and R were lower and LP longer than most other accessions. These resultsdemonstrated the existence of quantitative resistance to SMV in soybeans. It was foundthat some soybean accessions, such as AGS19 and Lishui Zhongzihuangdou, previouslyidentified as resistant to SMV infection, performed some infection but resistant toexpansion in the present study. In addition, the resistance in Pixian Chadou and HuaiyinQiuheidou might be either qualitative or quantitative. Furthermore, the present studyalso indicated that the resistance spectrum and durability of accessions with quantitativeresistance might be wider and longer than those with qualitative resistance. 展开更多
关键词 Soybean mosaic virus quantitative resistance Germplasm evaluation
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Evaluation of vibration stress of TA11 titanium alloy blade by quantitative fractography 被引量:5
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作者 Xin-Ling Liu Yuan-Ming Xu Chun-Hu Tao 《Rare Metals》 SCIE EI CAS CSCD 2014年第3期263-269,共7页
Vibration fatigue is the main failure mode of compressor blade. Evaluating the vibration stress of blade that leads to cracking is very useful for analysis of vibration fatigue. In this paper, fatigue stress estimatio... Vibration fatigue is the main failure mode of compressor blade. Evaluating the vibration stress of blade that leads to cracking is very useful for analysis of vibration fatigue. In this paper, fatigue stress estimation methods by quantitative fractography were studied through experimental blade and in-service first-stage compressor blade in order to evaluate the initiation vibration stress of in-service blade. The analysis process of initiation vibration stress was established. The evaluating result of vibration stress of in-service blade subjected to centrifugal force and bending vibration stress agrees with aero engine test result. It is shown that the evaluation method can not only evaluate the equivalent fatigue stresses of different crack depths but also yield the initiation equivalent fatigue stress. 展开更多
关键词 Compressor blade Bending vibration Stress evaluate quantitative fractography
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Evaluation of the weakening behavior of gas on the coal strength and its quantitative influence on the coal deformation 被引量:7
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作者 Haijun Guo Kai Wang +5 位作者 Yuchen Wu Hanlu Tang Jianguo Wu Lianhe Guan Chenyang Chang Chao Xu 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2021年第3期451-462,共12页
The coal strength and deformation properties are key factors affecting safe coal mining and highefficiency coalbed methane(CBM)development.In this paper,reconstituted coal samples are chosen to investigate the weakeni... The coal strength and deformation properties are key factors affecting safe coal mining and highefficiency coalbed methane(CBM)development.In this paper,reconstituted coal samples are chosen to investigate the weakening behavior of gas on coal strength,meanwhile,its effects on coal deformation are quantitatively evaluated.The results indicate that the weakening degree of gas on coal strength is closely related to the confining stress and gas pressure.Compared with non-gas-saturated coals,the maximum weakening ratios of adsorbed gas to coal strength are 10.58%,18.12%,8.55%and 14.65%under the conditions of confining stress CS=3 MPa and gas pressure GP=1 MPa,CS=3 MPa and GP=2 MPa,CS=4 MPa and GP=1 MPa,and CS=4 MPa and GP=2 MPa,respectively.Furthermore,the maximum weakening ratios of free gas to coal strength are 18.27%,36.54%,14.79%and 29.58%,respectively,under above four conditions.The maximum coal bulk strain decreases as particle sizes of coal powders increase,and it has a maximum value of 0.0227 and a minimum value of 0.0191 in particle size ranges of 0.01–0.041 and 0.5–1 mm.Under the same conditions,the coal bulk strain increases with increasing gas pressure,revealing that coal deformation properties can be enhanced by gas. 展开更多
关键词 Gas-saturated coal Coal strength Weakening effect Coal deformation quantitative evaluation Mechanical loading
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Quantitative evaluation of air pollution in transport strategic environmental assessment:a case study based on uncertainty analysis and graphic information system technology 被引量:3
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作者 Hong-tao BAI Hui-zhi WANG He XU Tan ZHU 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2010年第5期370-381,共12页
Although the impact of road transport on urban air quality has achieved a high profile in China,still greater attention is required as it has not yet been considered fully even in relation to the road network linking ... Although the impact of road transport on urban air quality has achieved a high profile in China,still greater attention is required as it has not yet been considered fully even in relation to the road network linking cities and urban areas. Strategic environmental assessment (SEA) is a systematic and comprehensive process for evaluating the environmental impacts of a policy,plan or program in publicly accountable decision-making. Air pollution has been recognized as a significant issue in most transport SEA practices. The Strategic Environmental Assessment of the Hubei Road Network Plan (2002-2020) (HRNP) was introduced as one of the World Bank's pilot SEA projects. An effective framework was developed to investigate the functional relationship between the road network and its potential air pollutant emissions. In this study,two indicators were identified:emission intensity/ inventory of pollutants and the spatial distribution of the most polluted areas. Because strategic actions are inherently nebulous and data quality is often disappointing,three alternative scenarios were employed to address uncertainties and data/scale issues. Calculations were made using emission models and results were analyzed with the help of statistical tools and the geographic information system (GIS). The results from the project implementation and the feedback from the World Bank have both shown that the proposed framework is effective in the transport SEA process. 展开更多
关键词 Air pollution Transport strategic environmental assessment (SEA) quantitative evaluation UNCERTAINTY
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Quantitative evaluation of soil erosion of land subsided by coal mining using RUSLE 被引量:13
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作者 Meng Lei Feng Qiyan +1 位作者 Wu Kan Meng Qingjun 《International Journal of Mining Science and Technology》 2012年第1期7-11,共5页
Based on a RUSLE model, we identified the key factors of the impact on soil erosion induced by coal min- ing subsidence. We designed a method for predicting/.S factors of a mining subsidence basin, using ana- lytical ... Based on a RUSLE model, we identified the key factors of the impact on soil erosion induced by coal min- ing subsidence. We designed a method for predicting/.S factors of a mining subsidence basin, using ana- lytical GIS spatial technology. Using the Huainan mining area as an example, we calculated the modulus of erosion, its volume and classified the grade of soil erosion for both the original area and the subsidence basin. The results show that the maximum modulus of erosion and the volume of erosion of the subsi- dence basin without water logging would increase by 78% and 23% respectively compared with the ori- ginal situation. The edge of the subsidence basin, where the land subsidence was uneven, is subject to the greatest acceleration in soil erosion. In the situation of water logging after subsidence, the maximum modulus of erosion would decrease if the accumulated slope length were reduced. This maximum mod- ulus around the water logged area within the subsidence basin is equal to that without water logging, while the total volume of erosion decreases. Therefore, mining subsidence aggravates soil erosion espe- cially at the edge of basins where water and soil conservation measures should be taken. 展开更多
关键词 RUSLE Coal mining subsidence Soil erosion quantitative evaluation
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Quantitative evaluation and spatial differentiation of eco-environmental livability in Zhejiang Province, China 被引量:5
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作者 WANG Yi ZHU Ying-ming +1 位作者 YU Mao-jun XU Jing 《Journal of Mountain Science》 SCIE CSCD 2020年第6期1491-1508,共18页
The scientific analyses of the spatial patterns of regional eco-environment livability,along with the explorations of the correlations between ecoenvironments and population and economic activity distributions,are of ... The scientific analyses of the spatial patterns of regional eco-environment livability,along with the explorations of the correlations between ecoenvironments and population and economic activity distributions,are of major significance in the guidance of the coordinated development between social economies,natural resources,and environments.In this study,the topography,climate,hydrology,land cover,air quality,and the dangers presented by natural hazards in the study area were investigated in order to establish an evaluation model for the regional eco-environmental livability.Then,the observed spatial patterns and regional differences in the eco-environmental livability,as well as their relationships with the distributions of population and economic activities in Zhejiang Province,were investigated.The results showed that the ecoenvironmental livability in Zhejiang Province displayed a gradual decreasing trend from southwest to northeast,as well as from the mountains to the hills,valleys,and plains areas.During the compartmentalization of the eco-environmental livability,it was observed that the lowest livable area covered the largest population,accounting for approximately 29.64%of the total population in the study area.The higher livable areas covered the widest land areas,accounting for approximately 26.15%of the total area.Moreover,it was found that the eco-environmental livability in the mountain areas was higher than that in the plain areas in Zhejiang Province.Furthermore,the ecoenvironmental livability was found to have a significant exponential relationship with the population and GDP densities of Zhejiang Province,with the R^2 of the curve-fittings reaching 0.835 and 0.656,respectively.However,it was determined that the coefficient of the exponential function was negative,which indicated that a strong negative relationship existed between the eco-environmental livability and densities of the population and economic activities.It was assumed that the impacts of anthropogenic factors were the fundamental causes of this negative correlation.This study introduced two new factors(air quality and natural hazards)into the evaluation framework of eco-environmental livability.As a result,a more comprehensive model was established for the evaluation of eco-environmenta livability in certain segments of the study area Additionally,the correlation between ecoenvironment livability and human activities was discussed in-depth,which can potentially provide theoretical and practical guidance for the implementation of eco-livability in China,and possibly even those of other vast developing countries. 展开更多
关键词 ECO-ENVIRONMENT LIVABILITY quantitative evaluations Spatial differentiation Zhejiang Province
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Synthetically quantitative evaluation function of characteristic parameters on CO_2 arc welding process 被引量:4
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作者 俞建荣 蒋力培 +2 位作者 史耀武 孙振国 王军波 《China Welding》 EI CAS 2001年第1期19-26,共8页
The statistical probability and their variation regularity of the measurable characteristic parameters in the CO 2 arc welding droplet short circuiting transfer process have been studied. The statistical analysis sh... The statistical probability and their variation regularity of the measurable characteristic parameters in the CO 2 arc welding droplet short circuiting transfer process have been studied. The statistical analysis shows that the sensitivity of each characteristic parameter with regard to the variation of the short circuiting transfer process is different. The sensitivity of 4 kinds among these characteristic parameters is more intense than that of the short circuiting transfer frequency. In order to take account of the synthetic influence of these characteristic parameters, by means of the characteristic parameters synthetic value, a quantitative evaluation function is built up to describe and evaluate the short circuiting transfer process of CO 2 arc welding in real time. The testing shows that the evaluation function can give a suitable synthetic valuation for the short circuiting transfer process with a variety of welding variables. 展开更多
关键词 CO 2 arc welding process characteristic parameters quantitative evaluation function
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