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Comparison of Crop Model Validation Methods 被引量:3
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作者 CAO Hong-xin Jim Scott Hanan +11 位作者 LIU Yan LIU Yong-xia YUE Yan-bin ZHU Da-wei LU Jian- fei SUNJin-ying SHI Chun-lin GE Dao-kuo WEI Xiu-fang YAO An-qing TIAN Ping-ping BAO Tai-lin 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2012年第8期1274-1285,共12页
In this paper, the many indices used in validation of crop models, such as RMSE (root mean square errors), Sd (standard error of absolute difference), da (mean absolute difference), dap (ratio of da to the mean... In this paper, the many indices used in validation of crop models, such as RMSE (root mean square errors), Sd (standard error of absolute difference), da (mean absolute difference), dap (ratio of da to the mean observation), r (correlation), and R2 (determination coefficient), are compared for the same rice architectural parameter model, and their advantages and disadvantages are analyzed. A new index for validation of crop models, dap between the observed and the simulated values, is proposed, with dap〈5% as the suggested standard for precision of crop models. The different kinds of validation methods in crop models should be combined in the following aspects:(1) calculating da and dap; (2) calculating the RMSE or Sd; (3) calculating r and R2, at the same time, plotting 1:1 diagram. 展开更多
关键词 crop models validation methods comparison
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Methods Comparison for Microsatellite Marker Development:Different Isolation Methods,Different Yield Efficiency 被引量:1
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作者 ZHAN Aibin BAO Zhenmin HU Xiaoli LU Wei HU Jingjie 《Journal of Ocean University of China》 SCIE CAS 2009年第2期161-165,共5页
Microsatellite markers have become one kind of the most important molecular tools used in various researches. A large number of microsatellite markers are required for the whole genome survey in the fields of molecula... Microsatellite markers have become one kind of the most important molecular tools used in various researches. A large number of microsatellite markers are required for the whole genome survey in the fields of molecular ecology,quantitative genetics and genomics. Therefore,it is extremely necessary to select several versatile,low-cost,efficient and time-and labor-saving methods to develop a large panel of microsatellite markers. In this study,we used Zhikong scallop(Chlamys farreri) as the target species to compare the efficiency of the five methods derived from three strategies for microsatellite marker development. The results showed that the strategy of constructing small insert genomic DNA library resulted in poor efficiency,while the microsatellite-enriched strategy highly improved the isolation efficiency. Although the mining public database strategy is time-and cost-saving,it is difficult to obtain a large number of microsatellite markers,mainly due to the limited sequence data of non-model species deposited in public databases. Based on the results in this study,we recommend two methods,microsatellite-enriched library construction method and FIASCO-colony hybridization method,for large-scale microsatellite marker development. Both methods were derived from the microsatellite-enriched strategy. The experimental results obtained from Zhikong scallop also provide the reference for microsatellite marker development in other species with large genomes. 展开更多
关键词 微卫星标记 分离方法 基因组DNA文库 分子生态学 公共数据库 产量 基因组学 数量遗传学
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Research on Comparison and Evaluation Studies of Several Smoothing Denoising Method Based on γ-ray Spectrum Detector 被引量:1
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作者 Jian-Feng He Fang Fang +2 位作者 Yao-Zong Yang Yue-Shun He Bin Tang 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2013年第2期7-11,共5页
The extraction of spectral parameters is very difficult because of the limited energy resolution for NaI( TI) gamma-ray detectors. For statistical fluctuation of radioactivity under complex environment,some smoothing ... The extraction of spectral parameters is very difficult because of the limited energy resolution for NaI( TI) gamma-ray detectors. For statistical fluctuation of radioactivity under complex environment,some smoothing filtering methods are proposed to solve the problem. These methods include adopting method of arithmetic moving average,center of gravity,least squares of polynomial,slide converter of discrete funcion convolution etc. The process of spectrum data is realized,and the results are assessed in H / FWHM( Peak High / Full Width at Half Maximum) and peak area based on the Matlab programming. The results indicate that different methods smoothed spectrum have respective superiority in different ergoregion,but the Gaussian function theory in discrete function convolution slide method is used to filter the complex γ-spectrum on Embedded system platform,and the statistical fluctuation of γ-spectrum is filtered well. 展开更多
关键词 γ-spectrum data-processing SMOOTHING DENOISING method comparison and EVALUATION matlab programming
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Comparison of Methods for Estimating Reference Crop Evapotranspiration in Beijing 被引量:1
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作者 Cao Yajie Shi Youyu +1 位作者 Mo Nannan Li Xin 《Meteorological and Environmental Research》 CAS 2019年第6期72-74,78,共4页
Based on the meteorological data from 1951 to 2015 in Beijing,the reference crop evapotranspiration(ET_0)in Beijing was estimated using the FAO 56 Penman-Monteith method,the FAO PPP-17 Penman method,the Hargreaves met... Based on the meteorological data from 1951 to 2015 in Beijing,the reference crop evapotranspiration(ET_0)in Beijing was estimated using the FAO 56 Penman-Monteith method,the FAO PPP-17 Penman method,the Hargreaves method,and the Priestley-Taylor method.The results showed that the monthly and annual changing trends of ET0 estimated by the four methods are basically the same.In general,the ET0 values estimated by the Hargreaves method are the closest to those of the standard method FAO 56 Penman-Monteith,while the difference between the FAO PPP-17 Penman method and the standard method is the biggest.The Hargreaves method is the most suitable method for the estimation of ET0 in Beijing. 展开更多
关键词 REFERENCE CROP EVAPOTRANSPIRATION ESTIMATION method comparison
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Quantitative comparison screening of seismological indexes and research on the integrated prediction method in North China
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作者 周翠英 朱元清 +3 位作者 王红卫 梁凯莉 李平 郭爱香 《Acta Seismologica Sinica(English Edition)》 CSCD 1999年第2期232-237,共6页
关键词 comparison screening method quantitative selecting SEISMOLOGY parameters INTEGRATED Prediction
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Performance Comparison of Two Efficient Genomic Selection Methods(gsbay & MixP ) Applied in Aquacultural Organisms
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作者 SU Hailin LI Hengde +2 位作者 WANG Shi WANG Yangfan BAO Zhenmin 《Journal of Ocean University of China》 SCIE CAS CSCD 2017年第1期137-144,共8页
Genomic selection is more and more popular in animal and plant breeding industries all around the world, as it can be applied early in life without impacting selection candidates. The objective of this study was to br... Genomic selection is more and more popular in animal and plant breeding industries all around the world, as it can be applied early in life without impacting selection candidates. The objective of this study was to bring the advantages of genomic selection to scallop breeding. Two different genomic selection tools Mix P and gsbay were applied on genomic evaluation of simulated data and Zhikong scallop(Chlamys farreri) field data. The data were compared with genomic best linear unbiased prediction(GBLUP) method which has been applied widely. Our results showed that both Mix P and gsbay could accurately estimate single-nucleotide polymorphism(SNP) marker effects, and thereby could be applied for the analysis of genomic estimated breeding values(GEBV). In simulated data from different scenarios, the accuracy of GEBV acquired was ranged from 0.20 to 0.78 by Mix P; it was ranged from 0.21 to 0.67 by gsbay; and it was ranged from 0.21 to 0.61 by GBLUP. Estimations made by Mix P and gsbay were expected to be more reliable than those estimated by GBLUP. Predictions made by gsbay were more robust, while with Mix P the computation is much faster, especially in dealing with large-scale data. These results suggested that both algorithms implemented by Mix P and gsbay are feasible to carry out genomic selection in scallop breeding, and more genotype data will be necessary to produce genomic estimated breeding values with a higher accuracy for the industry. 展开更多
关键词 GENOMIC SELECTION SCALLOP BREEDING method comparison
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Comparison of Four Diagnostic Tests Methods for the Detection of Dengue Virus Non-Structural-1 Antigen and IgM/IgG Antibodies
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作者 Moses N. Ikegbunam Ifeyinwa T.O. Onochie-Igbinedion +5 位作者 Nzube F. Ekpunobi Abone Harrison Enyi Emmanuel Simon Nkpeh Ushie Micheal U. Adiukwu Charles O. Esimone 《Journal of Biosciences and Medicines》 2022年第5期179-190,共12页
Objectives: Dengue virus (DENV) infection is a mosquito-borne disease that stands out as one of the major public health issues and has a wide-ranging geographical distribution throughout the tropics and subtropics. Th... Objectives: Dengue virus (DENV) infection is a mosquito-borne disease that stands out as one of the major public health issues and has a wide-ranging geographical distribution throughout the tropics and subtropics. The general alarming increase in the number of cases over the last two decades can be attributed to an extent by the change in national practices to keeping records and reporting dengue to the Ministries of Health, and WHO. Dengue diagnosis is routinely carried out by detection of dengue virus (DENV) antigen NS1 (Non-structural Antigen 1) and/or anti-DENV IgM/IgG antibodies using enzyme-linked immunosorbent assays (ELISAs) and rapid diagnostic tests (RDTs). This study compared the performance of three RDTs and one ELISA used for dengue diagnosis in southeastern, Nigeria. Design: This study adopted a cross-sectional design that included prospective hospital-based surveillance of cases among febrile participants attending two major health facilities within the southeastern region of Nigeria. In this study, 338 HIV-infected participants from two teaching hospitals in Nigeria’s southeast were systematically tested for Dengue with four methods: NS1 RDT, IgG RDT, IgM RDT, and NS1 ELISA. Their specificities and sensitivities were compared, as well as their level of concordance. Their respective performances were also evaluated using the Receivers Operational curve (ROC). Results: Out of the 338 patients, the dengue prevalence from the four dengue diagnostic methods Dengue virus NS1 ELISA, NS1 RDT, IgM and IgG seropositivity were 8.9%, 0.6%, 5.6%, and 8.0%, respectively. The Dengue IgM RDT test indicated 36.8% sensitivity, 92.8% specificity, the IgG anti-dengue specific test indicated 29.6% sensitivity, 92.9% specificity and the dengue NS1 RDT test indicated 3.3% sensitivity, 99.4% specificity when compared with the Dengue NSI Elisa test method as a reference method. Conclusion: The use of NSI ELISA for DENV diagnosis showed good performance and the RDTs showed, to an extent, reliable results compared with ELISA. However, diagnostic laboratories should be aware of performance variations across tests and the possibilities of cross-reactivity that may affect results. 展开更多
关键词 Dengue Virus Diagnosis methods comparison Performance Southeastern Nigeria
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Comparison of Three Methods in Extracting Coherent Modes from a Doppler Backscatter System
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作者 张小辉 刘阿娣 +7 位作者 周楚 胡健强 王明远 俞昌旋 刘万东 李弘 兰涛 谢锦林 《Chinese Physics Letters》 SCIE CAS CSCD 2015年第12期92-95,共4页
We compare three different methods to extract coherent modes from Doppler backscattering (DBS), which are center of gravity (COG) of the complex amplitude spectrum, spectrum of DBS phase derivative (phase derivat... We compare three different methods to extract coherent modes from Doppler backscattering (DBS), which are center of gravity (COG) of the complex amplitude spectrum, spectrum of DBS phase derivative (phase derivative method), and phase spectrum, respectively. These three methods are all feasible to extract coherent modes, for example, geodesic acoustic mode oscillation. However, there are stilI differences between dealing with high frequency modes (several hundred kHz) and low frequency modes, (several kHz) hiding in DBS signal. There is a significant amount of power at low frequencies in the phase spectrum, which can be removed by using the phase derivative method and COG. High frequency modes are clearer by using the COO and the phase derivative method than the phase spectrum. The spectrum of DBS amplitude does not show the coherent modes detected by using COG, phase derivative method and phase spectrum. When two Doppler shifted peaks exist, coherent modes and their harmonics appear in the spectrum of DBS amplitude, which are introduced by the DBS phase. 展开更多
关键词 DBS comparison of Three methods in Extracting Coherent Modes from a Doppler Backscatter System COG Figure
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Comparison of three methods for paternity test
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《中国输血杂志》 CAS CSCD 2001年第S1期384-,共1页
关键词 comparison of three methods for paternity test
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Comparison between Two Kinds of Methods of Locating Acupoints 
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作者 Ding Yidan,Li Jingming(Medical College of Jinan University) 《中国针灸》 CAS CSCD 北大核心 1995年第S2期375-375,共1页
ComparisonbetweenTwoKindsofMethodsofLocatingAcupoints¥DingYidan,LiJingming(MedicalCollegeofJinanUniversity)T... ComparisonbetweenTwoKindsofMethodsofLocatingAcupoints¥DingYidan,LiJingming(MedicalCollegeofJinanUniversity)Theproportionalmea... 展开更多
关键词 comparison between Two Kinds of methods of Locating Acupoints
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Comparison of Extraction Methods for Total Alkaloids from Abrus Cantoniensis Hance
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作者 Mengyao LIN Qiumeng WEI +7 位作者 Xiaoxia HUANG Jiaming WANG Suoyi HUANG Luyao WANG Yan LIU Gongxiao MO Xunjie LIANG Xiaoting MA 《Medicinal Plant》 2017年第2期19-21,共3页
[Objectives] To compare different extraction methods for total alkaloids from Abrus Cantoniensis Hance taking chloroform as solvent. [Methods] The ethanol extraction method,ultrasonic extraction method,acid water extr... [Objectives] To compare different extraction methods for total alkaloids from Abrus Cantoniensis Hance taking chloroform as solvent. [Methods] The ethanol extraction method,ultrasonic extraction method,acid water extraction method,and Soxhlet extraction method were used to extract total alkaloids,and the total alkaloids of Abrus Cantoniensis Hance were measured at 238 nm wavelength. [Results] The extraction rate of ethanol extraction method was 14. 76 mg/100 g; the extraction rate of ultrasonic extraction method was 56. 85 mg/100 g; the extraction rate of acid water extraction method was 56. 63 mg/100 g; the extraction rate of Soxhlet extraction method was 58. 19 mg/100 g.[Conclusions]Results indicate that Soxhlet extraction method can obtain the highest extraction rate. 展开更多
关键词 TOTAL ALKALOIDS Abrus Cantoniensis Hance EXTRACTION methodS comparison
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The Comparison between Audio-lingual Method and Communicative Language Teaching in the Foreign Language Teaching 被引量:1
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作者 张瑜 张汉伟 《海外英语》 2013年第5X期15-16,23,共3页
To increase the efficiency of teaching and improve the quality of teaching, it is necessary to learn the English teaching methodology and put the theory into practice. Audio-lingual Method and Communicative Language T... To increase the efficiency of teaching and improve the quality of teaching, it is necessary to learn the English teaching methodology and put the theory into practice. Audio-lingual Method and Communicative Language Teaching are very important methods in English language teaching. In this essay, I made a comparison and analysis based on their theories and practices. It is beneficial for us to proceed from the reality and use these methods appropriately. 展开更多
关键词 comparison Audio-lingual method COMMUNICATIVE lang
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Comparison of four methods of DNA extraction from rice
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作者 SONG Ming GUO Zhongxin GAO Zhiyong ZHANG Yunsun,Dept of Biotechnology,Yunnan Univ,Kunming 650091,China 《Chinese Rice Research Newsletter》 2002年第3期10-11,共2页
Polyphenols,teroens,and resinsmake it difficult to obtain high qualitygenomic DNA from rice.Four ex-traction methods were compared inour study,and CTAB precipitationwas the most practical one.Materials used were old l... Polyphenols,teroens,and resinsmake it difficult to obtain high qualitygenomic DNA from rice.Four ex-traction methods were compared inour study,and CTAB precipitationwas the most practical one.Materials used were old leavesfrom Ftransgenic rice in Hainan andfresh leaves from Ftransgenic rice inKunming.Procedures of the four methodswere as follows:1.Basical method:powder 1 gold or new leaves→added 2 ml ex-traction solution(100 mmol/L 展开更多
关键词 DNA CTAB comparison of four methods of DNA extraction from rice
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Quantitative comparison of cranial approaches in the anatomy laboratory: A neuronavigation based research method 被引量:1
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作者 Francesco Doglietto Jimmy Qiu +7 位作者 Mayoorendra Ravichandiran Ivan Radovanovic Francesco Belotti Anne Agur Gelareh Zadeh Marco Maria Fontanella Walter Kucharczyk Fred Gentili 《World Journal of Methodology》 2017年第4期139-147,共9页
AIM To describe the development and validation of a novel neuronavigation-based method, which allows the quan-tification of the anatomical features that define an approach, as well as real-time visualization of the su... AIM To describe the development and validation of a novel neuronavigation-based method, which allows the quan-tification of the anatomical features that define an approach, as well as real-time visualization of the surgical pyramid. METHODS The method was initially developed with commerciallyavailable hardware for coordinate collection(a digitizer and a frameless navigation system) and software for volume rendering; dedicated neuronavigation software(ApproachV iewer, part of GTx-UHN) was then developed. The accuracy of measurements and the possibility of volumetric rendering of surgical approaches simulated in a phantom were compared among three different methods and commercially-available radiological software. In the anatomy laboratory, ApproachV iewer was applied to the comparative quantitative analysis of multiple neurosurgical approaches and was used by many surgeons who were untrained for the research method.RESULTS The accuracy of ApproachV iewer is comparable to commercially-available radiological software. In the anatomy laboratory, the method appears versatile. The system can be easily used after brief training. ApproachV iewer allows for real-time evaluation and comparison of surgical approaches, as well as post-dissection analyses of collected data. The accuracy of the method depends on the navigation registration: with a 1-2 mm registration error, it is adequate for evaluation and comparison of most neurosurgical approaches.CONCLUSION This new research method and software allows semiautomated visualization, quantification, and comparison of neurosurgical approaches in the anatomy laboratory. 展开更多
关键词 Anatomical study comparison Neurosurgical approach Quantification Research method 3D rendering
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基于CLSI指南EP09-A3比对2套化学发光免疫分析系统血清TT_3测定结果
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作者 陈永伟 王静 +2 位作者 杨晓龙 胡芳宇 林芳 《检验医学》 CAS 2024年第2期176-180,共5页
目的 基于美国临床实验室标准化协会(CLSI)指南EP09-A3探讨2套化学发光免疫分析系统血清总三碘甲状腺原氨酸(TT_3)测定结果的可比性。方法 根据EP09-A3指南要求,使用2个品牌化学发光免疫分析系统(分别命名为系统一和系统二)分别测定111... 目的 基于美国临床实验室标准化协会(CLSI)指南EP09-A3探讨2套化学发光免疫分析系统血清总三碘甲状腺原氨酸(TT_3)测定结果的可比性。方法 根据EP09-A3指南要求,使用2个品牌化学发光免疫分析系统(分别命名为系统一和系统二)分别测定111例血清样本TT_3水平。通过广义极端学生化偏差(ESD)法检验离群值,选用EP09-A3指南列举的5种回归模型分析2套系统TT_3检测结果,并计算医学决定水平处的偏移。结果 散点图目测和ESD法检验均未发现离群值。2套系统TT_3检测结果的5种回归分析结果显示,一般线性回归、加权最小二乘法回归、Deming回归、Passing-Bablock回归分析在TT_3医学决定水平处(0.75和1.91 ng·mL~(-1))的偏移均<可接受范围[允许总误差(TEa)±12.5%],偏移的95%可信区间(CI)结果类型解读为可接受的A型和B型,加权Deming回归分析得到的偏移的95%CI部分超出可接受范围,结果类型解读为C型。结论 EP09-A3指南适用于2套系统检测TT_3的方法学比对和偏移评估,且该指南更新的离群值判断方法、回归分类分析法和对应的解读分型方式更为科学、合理。 展开更多
关键词 EP09-A3 总三碘甲状腺原氨酸 方法学比对 医学决定水平 偏移
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典型场景彩色夜视融合图像质量主观评价实验
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作者 高绍姝 倪潇 +3 位作者 孙士明 宋尚鸽 田琪琳 赵全强 《实验技术与管理》 CAS 北大核心 2024年第3期36-44,共9页
评价特定场景下红外和可见光(微光)彩色融合图像质量的研究对彩色夜视融合技术和嵌入式系统开发具有重要作用。由于主观评价实验能够得到与人眼感受一致的评价结果因而成为研究的热点。因此,该文针对海天、森林、城镇、乡村和特殊条件... 评价特定场景下红外和可见光(微光)彩色融合图像质量的研究对彩色夜视融合技术和嵌入式系统开发具有重要作用。由于主观评价实验能够得到与人眼感受一致的评价结果因而成为研究的热点。因此,该文针对海天、森林、城镇、乡村和特殊条件五个典型应用场景,提出基于动态参考的多刺激比较主观评价法,开展了大规模典型场景彩色融合图像主观评价实验,建立了包含1648幅彩色融合图像的质量主观评价数据库;此外,提出基于评价实验特性的模糊综合评判方法用于分析不同融合算法的场景适用性。实验数据一致性分析中,该主观评价法具有较高的皮尔逊相关系数,表明本文构建的数据集具有良好的有效性与可靠性。该文结果可为进一步开展夜视融合图像质量评价研究提供实验基础和理论依据。 展开更多
关键词 彩色融合图像 主观质量评价 多刺激比较法 典型场景 模糊综合评判
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振弦式土压力计自动校准系统设计及应用研究
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作者 李林 韩鸿胜 周振杰 《水道港口》 2024年第2期308-312,共5页
随着智慧港口和智慧航道建设的发展,监测传感器的自动化计量已成为未来发展趋势。通过分析监测传感器——振弦式土压力计的组成和工作原理、校准需求及难点,设计并研制了一套自动化校准系统。以工控机为控制核心,以自动加压系统、频率... 随着智慧港口和智慧航道建设的发展,监测传感器的自动化计量已成为未来发展趋势。通过分析监测传感器——振弦式土压力计的组成和工作原理、校准需求及难点,设计并研制了一套自动化校准系统。以工控机为控制核心,以自动加压系统、频率采集仪为标准器,通过控制系统自动加压和测量被检设备输出频率模数值,可实现压力标准值的设置输出、频率测量值的自动记录存储及运算处理、历史数据管理及生成校准报告等目标。试验表明其各项程序和指标均能满足振弦式土压力计的校准要求,可直接用于相关计量校准工作。 展开更多
关键词 智慧港口 智慧航道 土压力计 校准 比较法
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不同类型多肉植物的花粉活力检测方法筛选及活力鉴定
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作者 杨澜 曾春雪 +2 位作者 王维泽 韦朝妹 陈之林 《种子》 北大核心 2024年第2期120-126,F0002,共8页
以3个科6个属的13种多肉植物种质资源为材料,对比亚历山大染色法和碘-碘化钾(I2-KI)染色法染色后花粉活力的差异,筛选适宜不同类型多肉植物花粉活力的测定方法。结果表明,两种染色法对不同科属的多肉植物花粉染色结果差异极显著,I2-KI... 以3个科6个属的13种多肉植物种质资源为材料,对比亚历山大染色法和碘-碘化钾(I2-KI)染色法染色后花粉活力的差异,筛选适宜不同类型多肉植物花粉活力的测定方法。结果表明,两种染色法对不同科属的多肉植物花粉染色结果差异极显著,I2-KI染色法检测的花粉活力平均值显著低于亚历山大染色法;种质资源的花粉活力普遍高于杂交组合,聚类分析结合差异显著性分析将26种目标种质资源及杂交组合的花粉活力划分为5个等级;显微镜下花粉形状呈现圆形、方形、椭圆形和不规则形,且同一品种存在一种到多种的花粉萌发孔形态。 展开更多
关键词 多肉植物 花粉活力 染色法对比 活力等级划分
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Comparison of methods for identification of cold tolerance of rice
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作者 LIU Yanzhuo CHEN Zhaoming ZHANG Xu LIN Daoxuan KONG Qingui Rice Research Institute,Guangdong Academy of Agricultural Sciences,Guangzhou 510640,China 《Chinese Rice Research Newsletter》 1991年第3期3-4,共2页
Under low temperature stress,theplasmamembrane and chloroplast of plant cellsare impaired,resulting in electrolyte leakage and al-teration of chlorophyll fluorescence which can bemeasured with conductometer and fluore... Under low temperature stress,theplasmamembrane and chloroplast of plant cellsare impaired,resulting in electrolyte leakage and al-teration of chlorophyll fluorescence which can bemeasured with conductometer and fluoremeter.The cold tolerance of excised leaves of several ricevarieties were determined with these two instru-ments at seedling and heading stages to compare 展开更多
关键词 comparison of methods for identification of cold tolerance of rice
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基于UPLC-Triple-TOF-MS技术初步分析雅安产道地中药材川牛膝中生物碱成分
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作者 王悦秋 王昌 +1 位作者 梁林辉 梁大伟 《山东化工》 CAS 2024年第3期155-157,160,共4页
采用乙醇提取、成盐、二氯甲烷萃取等方法初步富集川牛膝总生物碱,确定最优提取分离工艺;通过超高液相色谱串联三重四级杆飞行时间质谱法,采用Waters XSelect CSH-C_(18)色谱柱(2.1 mm×150 mm,1.7μm),梯度洗脱,流速为0.3 mL/min,... 采用乙醇提取、成盐、二氯甲烷萃取等方法初步富集川牛膝总生物碱,确定最优提取分离工艺;通过超高液相色谱串联三重四级杆飞行时间质谱法,采用Waters XSelect CSH-C_(18)色谱柱(2.1 mm×150 mm,1.7μm),梯度洗脱,流速为0.3 mL/min,测试波长254 nm,柱温为50℃,进样量为3μL,采用电喷雾离子源正离子模式,扫描范围为m/z 100~1500,并采用全扫描模式对样品数据进行收集,根据高分辨质谱结合二级质谱所得信息对川牛膝中生物碱类化学成分进行快速鉴定,通过对比分子离子峰和碎片离子的质荷比、Scifinder和Reaxy数据库及相关文献,推测出两种生物碱成分。研究建立的生物碱类化学成分提取与分析方法,为提高雅安产道地中药材川牛膝的质量控制水平及后续阐明药效物质基础提供了实验依据。 展开更多
关键词 川牛膝 生物碱 提取方法 超高液相色谱串联三重四级杆飞行时间质谱法 定性分析
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