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A Comparison of Microbial Communities in Three Morphs of the Rhynchophorus ferrugineus (Olivier), a Key Pest of Date Palms
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作者 AbdulAziz M. A. Mohamed Malabika Roy Pathak +2 位作者 Muhammad Farooq Jennifer A. White Laura C. Rosenwald 《Advances in Bioscience and Biotechnology》 CAS 2024年第10期556-572,共17页
The invasive insect pest, red palm weevil (RPW), Rhynchophorus ferrugineus, poses a significant threat to date production, causing substantial economic damage. If uncontrolled, RPW leads the severely infested host tre... The invasive insect pest, red palm weevil (RPW), Rhynchophorus ferrugineus, poses a significant threat to date production, causing substantial economic damage. If uncontrolled, RPW leads the severely infested host tree to collapse and eventually die. The symbiotic associations with microorganisms and RPW in their gut may help their host insects’ establishment, development, nutrition assimilation, and survival. The objective of this research was the molecular characterization of the microbiome of RPW. In this study, the microbiome was compared among different tissues in females and males of RPW of three different morphs and larvae collected from date palm plantations in the Kingdom of Bahrain. A 251-bp segment of bacterial 16S rRNA was amplified by PCR, sequenced, and processed using the bioinformatics platform QIIME2. One ASV, corresponding to the obligate weevil symbiont Nardonella, predominated in adult female samples, constituting 56 ± 7% of total reads, but was less dominant in male samples (12 ± 3%) and larval samples (2.6 ± 1.9%). For females, samples that included reproductive tissues were almost entirely composed of Nardonella (88% - 99%). When Nardonella was excluded from analyses, there were no differences between adult females and adult males, but larval samples were more species-rich and differed in microbial composition from adults. There were no consistent differences in the microbiomes among morphs. Several specimens showed evidence of infection with host-specific strains of Spiroplasma-like members of the Entomoplasmatales, which are often pathogens or vertically transmitted symbionts. Such close microbial associates deserve additional attention as potential routes to control this destructive date palm pest. 展开更多
关键词 date Palm Rhynchophorus ferruginous GUT ENDOSYMBIONTS BACTERIA Nardonella
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Estimating Key Phenological Dates of Multiple Rice Accessions Using Unmanned Aerial Vehicle-Based Plant Height Dynamics for Breeding
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作者 HONG Weiyuan LI Ziqiu +5 位作者 FENG Xiangqian QIN Jinhua WANG Aidong JIN Shichao WANG Danying CHEN Song 《Rice science》 SCIE CSCD 2024年第5期617-628,I0066-I0070,共17页
Efficient and high-quality estimation of key phenological dates in rice is of great significance in breeding work. Plant height(PH) dynamics are valuable for estimating phenological dates. However, research on estimat... Efficient and high-quality estimation of key phenological dates in rice is of great significance in breeding work. Plant height(PH) dynamics are valuable for estimating phenological dates. However, research on estimating the key phenological dates of multiple rice accessions based on PH dynamics has been limited. In 2022, field traits were collected using unmanned aerial vehicle(UAV)-based images across 435 plots, including 364 rice varieties. PH, dates of initial heading(IH) and full heading(FH), and panicle initiation(PI), and growth period after transplanting(GPAT) were collected during the rice growth stage. PHs were extracted using a digital surface model(DSM) and fitted using Fourier and logistic models. Machine learning algorithms, including multiple linear regression, random forest(RF), support vector regression, least absolute shrinkage and selection operator, and elastic net regression, were employed to estimate phenological dates. Results indicated that the optimal percentile of the DSM for extracting rice PH was the 95th(R^(2) = 0.934, RMSE = 0.056 m). The Fourier model provided a better fit for PH dynamics compared with the logistic models. Additionally, curve features(CF) and GPAT were significantly associated with PI, IH, and FH. The combination of CF and GPAT outperformed the use of CF alone, with RF demonstrating the best performance among the algorithms. Specifically, the combination of CF extracted from the logistic models, GPAT, and RF yielded the best performance for estimating PI(R^(2) = 0.834, RMSE = 4.344 d), IH(R^(2) = 0.877, RMSE = 2.721 d), and FH(R^(2) = 0.883, RMSE = 2.694 d). Overall, UAV-based rice PH dynamics combined with machine learning effectively estimated the key phenological dates of multiple rice accessions, providing a novel approach for investigating key phenological dates in breeding work. 展开更多
关键词 phenological date plant height unmanned aerial vehicle machine learning rice breeding
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Effect of dates on blood glucose and lipid profile among patients with type 2 diabetes
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作者 Hyder Osman Mirghani 《World Journal of Diabetes》 SCIE 2024年第6期1079-1085,共7页
Poor fruit and vegetable consumption is one of the 10 major risk factors for mortality.There is a misconception regarding the consumption of dates among patients with diabetes.This manuscript assessed the effects of d... Poor fruit and vegetable consumption is one of the 10 major risk factors for mortality.There is a misconception regarding the consumption of dates among patients with diabetes.This manuscript assessed the effects of date consumption on fasting and postprandial blood glucose,glycated hemoglobin,total cholesterol,triglycerides,low-density lipoproteins,high-density lipoproteins,and microbial markers.Four literature databases were searched for relevant articles.Of the 595 studies retrieved,24 assessed the effects of dates on glycemic control and lipids.Overall,the evidence suggests that dates have a lowering effect on blood glucose.Dates reduce total cholesterol and triglyceride levels and increase high-density lipoprotein levels.Dates also promote the abundance of beneficial gut microbiota.Therefore,patients with diabetes and dyslipidemia can consume dates to reduce their blood glucose,cholesterol,and triglycerides. 展开更多
关键词 dateS Lipid profile Blood glucose Diabetes mellitus Microbial contamination
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Effects of Seeding Date and Density on Yield and Agronomic Traits of Millet : A Case Study of Wangu 098 Variety of Millet
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作者 Yinting NIU Le JU +3 位作者 Peiyu CHEN Zhigang YIN Xuejie QIANG Junxia LI 《Asian Agricultural Research》 2024年第4期33-36,共4页
[Objectives]To find out a suitable cultivation technique of Wangu 098 in Nanyang area,speed up the popularization,demonstration and application of Wangu 098,and provide a theoretical and practical basis for adjusting ... [Objectives]To find out a suitable cultivation technique of Wangu 098 in Nanyang area,speed up the popularization,demonstration and application of Wangu 098,and provide a theoretical and practical basis for adjusting the planting structure and realizing the matching of improved varieties and methods.[Methods]The new self-bred millet variety Wangu 098 was used as the material,and the two-factor split zone experimental design was adopted.The effects of different sowing dates and densities on the yield,growth period and agronomic characters of millet were studied.[Results]The interaction of seeding date and density had a great effect on the yield and plant traits of millet.Millet yield was significantly and positively correlated with plant height,panicle length,single panicle weight,panicle grain weight and tiller number.[Conclusions]The reasonable combination of seeding date and density could give full play to the yield potential of millet.According to the experimental results and cultivation experience,the suitable seeding date of millet in Nanyang area is in the first and middle ten days of June,and the best density is about 750000 plants/ha.However,after June 30,the seeding millet did not tiller,so the density should be increased to more than 900000 plants/ha to obtain higher yield.In terms of cultivation and management,timely seeding,reasonable close planting,and coordination of vegetative growth and reproductive growth can make the plant tall and strong,panicle long and thick,and improve the yield of millet. 展开更多
关键词 Wangu 098 MILLET SEEDING date DENSITY AGRONOMIC traits YIELD
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以学生为中心的BOPPPS教学模型+DATE监控模式在药理学教学中的应用探索
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作者 赵丽琼 《中国科技经济新闻数据库 教育》 2024年第8期0182-0185,共4页
随着教育改革的推广和深入,当前教学的模式开始逐渐的丰富化和多元化,各个教学理念、教学模型层出不穷,在这样的背景下,结合学科的特质和需求,设计良好的教学模式,认知理论和构建主义是BOPPPS教学模型的理论和依据,该模型是一个能够帮... 随着教育改革的推广和深入,当前教学的模式开始逐渐的丰富化和多元化,各个教学理念、教学模型层出不穷,在这样的背景下,结合学科的特质和需求,设计良好的教学模式,认知理论和构建主义是BOPPPS教学模型的理论和依据,该模型是一个能够帮助教师分解并分析教学过程、找出教学盲点、改善并提升教学成效的工具。如何使学生在课堂上最大限度的掌握知识,是其关注的重点,教学互动和反馈是其突出的特点。BOPPPS教学模型就是一个基于体验式学习模型的教学框架,是一种有效的课程设计模式,强调学生主动参与式学习,体现“以学生为中心、教师为主导”教学理念设计,为高质量的有效课堂提供了理论基础。因此,本文旨在探讨以学生为中心的BOPPPS教学模型与DATE监控模式在药理学教学中的应用及其效果。通过实践与研究,发现BOPPPS模型能够有效地提高学生的主动参与度和学习效果,而DATE监控模式则有助于及时发现和解决学生学习中的问题。以供一线教学教师作为教学提供参考和依据,有效提升药理学教学质量。 展开更多
关键词 以学生为中心 BOPPPS教学模型 date监控模式 药理学
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Effects of sowing date and ecological points on yield and the temperature and radiation resources of semi-winter wheat 被引量:2
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作者 ZHANG Zhen-zhen CHENG Shuang +7 位作者 FAN Peng ZHOU Nian-bing XING Zhi-peng HU Ya-jie XU Fang-fu GUO Bao-wei WEI Hai-yan ZHANG Hong-cheng 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2023年第5期1366-1380,共15页
Exploring the effects of sowing date and ecological points on the yield of semi-winter wheat is of great significance.This study aims to reveal the effects of sowing date and ecological points on the climate resources... Exploring the effects of sowing date and ecological points on the yield of semi-winter wheat is of great significance.This study aims to reveal the effects of sowing date and ecological points on the climate resources associated with wheat yield in the Rice–Wheat Rotation System.With six sowing dates,the experiments were carried out in Donghai and Jianhu counties,Jiangsu Province,China using two semi-winter wheat varieties as the objects of this study.The basic seedlings of the first sowing date (S1) were planted at 300×10^(4)plants ha^(-1),which was increased by 10%for each of the delayed sowing dates (S2–S6).The results showed that the delay of sowing date decreased the number of days,the effective accumulated temperature and the cumulative solar radiation in the whole growth period.The yields of S1 were higher than those of S2 to S6 by 0.22–0.31,0.5–0.78,0.86–0.98,1.14–1.38,and 1.36–1.59 t ha^(–1),respectively.For a given sowing date,the growth days increased as the ecological point was moved north,while both mean daily temperature and effective accumulative temperature decreased,but the cumulative radiation increased.As a result,the yields at Donghai County were 0.01–0.39 t ha–1lower than those of Jianhu County for the six sowing dates.The effective accumulative temperature and cumulative radiation both had significant positive correlations with yield.The average temperature was significantly negatively correlated with the yield.The decrease in grain yield was mainly due to the declines in grains per spike and 1 000-grain weight caused by the increase in the daily temperature and the decrease in the effective accumulative temperature. 展开更多
关键词 WHEAT YIELD SOWING date ECOLOGICAL point
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Untargeted metabolomics analysis of four date palm(Phoenix dactylifera L.)cultivars using MS and NMR
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作者 Shuruq Alsuhaymi Upendra Singh +7 位作者 Inas Al-Younis Najeh M.Kharbatia Ali Haneef Kousik Chandra Manel Dhahri Mohammed A.Assiri Abdul-Hamid Emwas Mariusz Jaremko 《Natural Products and Bioprospecting》 CSCD 2023年第1期247-265,共19页
Since ancient times,the inhabitants of dry areas have depended on the date palm(Phoenix dactylifera L.)as a staple food and means of economic security.For example,dates have been a staple diet for the inhabitants of t... Since ancient times,the inhabitants of dry areas have depended on the date palm(Phoenix dactylifera L.)as a staple food and means of economic security.For example,dates have been a staple diet for the inhabitants of the Arabian Peninsula and Sahara Desert in North Africa for millennia and the local culture is rich in knowledge and experience with the benefits of dates,suggesting that dates contain many substances essential for the human body.Madinah dates are considered one of the most important types of dates in the Arabian Peninsula,with Ajwa being one of the most famous types and grown only in Madinah,Saudi Arabia.Date seeds are traditionally used for animal feed,seed oil production,cosmetics,and as a coffee substitute.Phytochemical compounds that have been detected in date fruits and date seeds include phenolic acids,carotenoids,and flavonoids.Phenolic acids are the most prevalent bioactive constituents that contribute to the antioxidant activity of date fruits.The bioactive properties of these phytochemicals are believed to promote human health by reducing the risk of diseases such as chronic inflammation.Ajwa dates especially are thought to have superior bioactivity properties.To investigate these claims,in this study,we compare the metabolic profiles of Ajwa with different types of dates collected from Saudi Arabia and Tunisia.We show by UHPLC-MS that date seeds contain several classes of flavonoids,phenolic acids,and amino acid derivatives,including citric acid,malic acid,lactic acid,and hydroxyadipic acid.Additionally,GC-MS profiling showed that date seeds are richer in metabolite classes,such as hydrocinnamic acids(caffeic,ferulic and sinapic acids),than flesh samples.Deglet N fruit extract(minimum inhibitory concentration:27 MIC/μM)and Sukkari fruit extract(IC_(50):479±0.58μg/mL)have higher levels of antibacterial and antioxidative activity than Ajwa fruits.However,the seed analysis showed that seed extracts have better bioactivity effects than fruit extracts.Specifically,Ajwa extract showed the best MIC and strongest ABTS radical-scavenging activity among examined seed extracts(minimum inhibitory concentration:20μM;IC_(50):54±3.61μg/mL).Our assays are a starting point for more advanced in vitro antibacterial models and investigation into the specific molecules that are responsible for the antioxidative and anti-bacterial activities of dates. 展开更多
关键词 Metabolomics GC-MS UHPLC-MS NMR date palm PHYTOCHEMICALS
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Influence of Planting Date on the Incidence and Severity of Leaf Spot Disease in Telfairia occidentalis Hook f.
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作者 Agyingi Lucy Ambang Kebei Andrew Kpu Mbong Grace Annih 《Agricultural Sciences》 2023年第9期1169-1178,共10页
Telfairia occidentalis Hook f. is attacked by a destructive fungal pathogen Epicoccum sorghinum which causes leaf spot disease in the field. In Came-roon, this critically important seed and leaf vegetable is predomina... Telfairia occidentalis Hook f. is attacked by a destructive fungal pathogen Epicoccum sorghinum which causes leaf spot disease in the field. In Came-roon, this critically important seed and leaf vegetable is predominantly culti-vated under natural environmental conditions. An experiment was conducted in 2019 and 2020 during the long and short rainy seasons in Santchou to de-termine the influence of planting dates between seasons on the incidence and severity of leaf spot disease. The design used was a 2 by 4 factorial random-ized complete block design with three replications and four sowing dates. Data for disease incidence and severity documented fortnightly, were submitted to analysis of variance using SPSS version 23, and the means were separated by Duncan’s multiple range test (DMRT) at a 95% confidence interval. Statistical analysis revealed that the long rainy season registered a significantly (p p < 0.05) disease incidences and severities to other planting dates investi-gated. We established that the first three planting dates in the long rainy season could be a management practice to reduce disease prevalence. 展开更多
关键词 Leaf Spot Planting date SEASON Telfairia occidentalis
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In Situ Rb-Sr Dates of Muscovite and Sulfur Isotope of Pyrite from the Yangshan Gold Deposit in Western Qinling,China
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作者 HUANG Yong QI Xianmao +10 位作者 WU Qingsong LI Jianzhong REN Minghua DUAN Liu’an XIONG Tao YANG Zhonghu ZHAO Yang CIREN Lamu WEI Wei DUAN Jilin YAN Mengmeng 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2023年第5期1475-1489,共15页
Located along the southern part of the West Qinling orogenic belt,the Yangshan gold deposit is one of the largest in China.The major gold ores of Yangshan are disseminated in metasedimentary host rocks with minor nati... Located along the southern part of the West Qinling orogenic belt,the Yangshan gold deposit is one of the largest in China.The major gold ores of Yangshan are disseminated in metasedimentary host rocks with minor native gold amounts in stibnite-gold quartz veins.Pyrite and arsenopyrite are the major Au-bearing minerals.Hydrothermal muscovite from gold-bearing quartz veins was dated using the in situ Rb-Sr method to determine the formation age of the Yangshan gold deposit.The Rb-Sr isochron date of the muscovite yielded 210.1±5.6 Ma(MSWD=1.2).This date is near the lower end of the period of the mineralized granitic dykes(210.49-213.10 Ma).Two stages of gold enriching process are recognized in the gold-bearing pyrite:the first is incorporated with the Co,Cu,As,Ni enrichment;and the second is accompanied by Bi,Co,Ni,Pb,Cu,Sb concentration.The in-situ sulfur isotopic values of pyrites show a restrictedΔ34s range of-1.43‰to 2.86‰with a mean value of 0.43‰.Trace-element mapping and in-situ sulfur isotopic analysis of pyrite suggest that the sulfur deposits are likely derived from a magmatic source and likely assimilated by sulfur from the sedimentary bedrock.Thus,magmatism plays a critical role in the formation of the Yangshan gold deposit. 展开更多
关键词 Rb-Sr dating trace-element mapping sulfur isotope gold deposit Yangshan Qinling orogenic belt
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Investigation of Aegilops umbellulata for stripe rust resistance,heading date,and the contents of iron,zinc,and gluten protein
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作者 SONG Zhong-ping ZUO Yuan-yuan +5 位作者 XIANG Qin LI Wen-jia LI Jian LIU Gang DAI Shou-fen YAN Ze-hong 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2023年第4期1258-1265,共8页
Aegilops umbellulata(UU)is a wheat wild relative that has potential use in the genetic improvement of wheat.In this study,46 Ae.umbellulata accessions were investigated for stripe rust resistance,heading date(HD),and ... Aegilops umbellulata(UU)is a wheat wild relative that has potential use in the genetic improvement of wheat.In this study,46 Ae.umbellulata accessions were investigated for stripe rust resistance,heading date(HD),and the contents of iron(Fe),zinc(Zn),and seed gluten proteins.Forty-two of the accessions were classified as resistant to stripe rust,while the other four accessions were classified as susceptible to stripe rust in four environments.The average HD of Ae.umbellulata was significantly longer than that of three common wheat cultivars(180.9 d vs.137.0 d),with the exception of PI226500(138.9 d).The Ae.umbellulata accessions also showed high variability in Fe(69.74-348.09 mg kg^(-1))and Zn(49.83-101.65 mg kg^(-1))contents.Three accessions(viz.,PI542362,PI542363,and PI554399)showed relatively higher Fe(230.96-348.09 mg kg^(-1))and Zn(92.46-101.65 mg kg^(-1))contents than the others.The Fe content of Ae.umbellulata was similar to those of Ae.comosa and Ae.markgrafii but higher than those of Ae.tauschii and common wheat.Aegilops umbellulata showed a higher Zn content than Ae.tauschii,Ae.comosa,and common wheat,but a lower content than Ae.markgrafii.Furthermore,Ae.umbellulata had the highest proportion of γ-gliadin among all the species investigated(Ae.umbellulata vs.other species=mean 72.11%vs.49.37%;range:55.33-86.99%vs.29.60-67.91%).These results demonstrated that Ae.umbellulata exhibits great diversity in the investigated traits,so it can provide a potential gene pool for the genetic improvement of these traits in wheat. 展开更多
关键词 Aegilops umbellulata stripe rust resistance heading date Fe and Zn gluten proteins genetic variation
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Modeling Date Palm Trunk Fibers (DPTF) Packed Bed Adsorption Performances for Cadmium Removal from Aqueous Wastewater
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作者 Ahmad S.Awad Banan Hudaib Waid Omar 《Fluid Dynamics & Materials Processing》 EI 2023年第6期1535-1549,共15页
In this study,the potential of a low-cost bio-adsorbent,taken directly from Date Palm Trunk Fibers(DPTF)agricultural wastes,for cadmium ions removal from wastewaters is examined.The performances of this adsorbent are ... In this study,the potential of a low-cost bio-adsorbent,taken directly from Date Palm Trunk Fibers(DPTF)agricultural wastes,for cadmium ions removal from wastewaters is examined.The performances of this adsorbent are evaluated by building breakthrough curves at different bed heights and flow rates while keeping other parameters,such as the initial feed concentration,pH,and particle size,constant.The results indicate that the maximum cadmium adsorption capacity of DTPF can be obtained from the Thomas model as 51.5 mg/g with the most extended mass transfer zone of 83 min at the lowest flow rate at 5 ml/min.The saturation concentrations(NO)and the rate constant(kab)obtained from the BDST(bed depth service time)model are 7022.16 mg/l and 0.0536 l/mg.min,respectively.Using the Yon-Nelsen Model,it is found that operating at a lower flow rate leads to a larger value of the elapsed needed time to reach a 50%breakthrough.The Wolborska model indicates that the bed capacity increases with decreasing the flow rate,and the adsorbent can achieve a greater external mass transfer kinetic coefficient(2.271/min)at a higher flow rate. 展开更多
关键词 Cadmium ions ADSORPTION fixed bed biodorbent POLLUTANT date palm trunk fibers wastewater treatment breakthrough curves MODELING
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大麦茎、叶、穗对饲草产量及品质的影响 被引量:1
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作者 赵斌 季昌好 +3 位作者 孙皓 朱斌 王瑞 陈晓东 《麦类作物学报》 CAS CSCD 北大核心 2024年第7期865-870,共6页
为探明大麦不同组织(茎、叶和穗)在不同刈割期对饲草产量及品质的影响,以安徽省两个主栽饲用大麦品种为材料,比较了两年度两个品种茎、叶和穗分别在齐穗期及其后14 d和28 d饲草产量及品质的差异。结果显示,不同组织、刈割期及组织×... 为探明大麦不同组织(茎、叶和穗)在不同刈割期对饲草产量及品质的影响,以安徽省两个主栽饲用大麦品种为材料,比较了两年度两个品种茎、叶和穗分别在齐穗期及其后14 d和28 d饲草产量及品质的差异。结果显示,不同组织、刈割期及组织×刈割期互作效应对饲草产量及品质均有显著影响(P<0.05),年度效应主要影响产量,其他互作效应因品种和性状不同而异。饲草产量随刈割期后移增加,对其贡献表现为茎﹥穗﹥叶,第2年度高于第1年度。饲草品质性状在组织间和刈割期间存在显著差异,而在年度间仅在单个品种若干性状上存在差异;粗蛋白含量表现为穗﹥叶﹥茎,且随刈割期后移下降;粗纤维、酸性洗涤纤维、中性洗涤纤维和酸性洗涤木质素含量均为茎﹥叶﹥穗,且随刈割期后移前3个性状先降后升,酸性洗涤木质素含量持续上升;粗脂肪含量为叶﹥穗﹥茎,且随刈割期后移上升。综上,在株高相当时,增加穗部比例可提高大麦饲草产量和品质;刈割期后移可提升饲草产量但降低品质。基于本研究,选育大穗、多叶型品种,适期刈割,有望同步提升大麦饲草产量和品质。 展开更多
关键词 大麦 组织 刈割期 饲草产量 饲草品质
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Detecting Climate Change Trend, Size, and Change Point Date on Annual Maximum Time Series Rainfall Data for Warri, Nigeria
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作者 Masi G. Sam Ify L. Nwaogazie +2 位作者 Chiedozie Ikebude Chigozie Dimgba Diaa W. El-Hourani 《Open Journal of Modern Hydrology》 2023年第3期165-179,共15页
The study focused on the detection of indicators of climate change in 24-hourly annual maximum series (AMS) rainfall data collected for 36 years (1982-2017) for Warri Township, using different statistical methods yiel... The study focused on the detection of indicators of climate change in 24-hourly annual maximum series (AMS) rainfall data collected for 36 years (1982-2017) for Warri Township, using different statistical methods yielded a statistically insignificant positive mild trend. The IMD and MCIMD downscaled model’s time series data respectively produced MK statistics varying from 1.403 to 1.4729, and 1.403 to 1.463 which were less than the critical Z-value of 1.96. Also, the slope magnitude obtained showed a mild increasing trend in variation from 0.0189 to 0.3713, and 0.0175 to 0.5426, with the rate of change in rainfall intensity at 24 hours duration as 0.4536 and 0.42 mm/hr.year (4.536 and 4.2 mm/decade) for the IMD and the MCIMD time series data, respectively. The trend change point date occurred in the year 2000 from the distribution-free CUSUM test with the trend maintaining a significant and steady increase from 2010 to 2015. Thus, this study established the existence of a trend, which is an indication of a changing climate, and satisfied the condition for rainfall Non-stationary intensity-duration-frequency (NS-IDF) modeling required for infrastructural design for combating flooding events. 展开更多
关键词 Climate Change Annual Maximum Series Statistical Test Rainfall Trend and Size Change Point date
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柴达木盆地东北部拉合根地区中生代火山岩的发现及其地质意义:来自地球化学与锆石年代学证据 被引量:1
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作者 郑英 韩杰 +3 位作者 张小永 缑明亮 王明 袁博武 《现代地质》 CAS CSCD 北大核心 2024年第4期1147-1161,共15页
柴达木盆地北缘东部地区哇洪山—温泉断裂与宗务隆山南缘断裂之间地带出露系列火山岩,由于其中一部分缺乏精确的地质年代学制约,导致其地层归属难以确定,因此该地区大地构造单元划分尚存争议。本文基于详细的野外调查,在柴达木盆地北缘... 柴达木盆地北缘东部地区哇洪山—温泉断裂与宗务隆山南缘断裂之间地带出露系列火山岩,由于其中一部分缺乏精确的地质年代学制约,导致其地层归属难以确定,因此该地区大地构造单元划分尚存争议。本文基于详细的野外调查,在柴达木盆地北缘东部拉合根地区新识别出一套中生代火山岩,岩石类型为流纹岩、中酸性角砾熔岩及英安岩。对代表性流纹岩样品进行LA-ICP-MS锆石U-Pb定年,获得^(206)Pb/^(238)U加权平均年龄为(248.3±1.2)Ma(MSWD=0.30,n=20),表明岩石形成于早三叠世。全岩元素组成分析结果显示,该火山岩为准铝质高钾钙碱性岩石,轻重稀土元素分馏明显,轻稀土元素富集、重稀土元素亏损,δEu平均值为0.63,显示为弱负异常;微量元素呈现Rb、Ba等大离子亲石元素和Th、U、Hf和Zr等高场强元素相对富集,Sr强烈亏损,Ta、Nb相对亏损的特征,具有典型岛弧火山岩地球化学特征。锆石εHf(t)值分布范围为-19.62~-3.07,对应的t_(DM2)为2421~1639 Ma,表明岩石来自古元古代地壳物质的部分熔融。综合岩石年代学和地球化学特征,认为该火山岩为早三叠世阿尼玛卿洋向北俯冲于东昆仑地块,导致地壳基底(如达肯大坂岩群)发生深熔作用的产物。通过区域对比,提出该火山岩与鄂拉山岩浆弧洪水川组火山岩的地球化学性质较为相似,因此将其厘定为下三叠统洪水川组火山岩。该火山岩的发现指示拉合根地区大地构造单元属于东昆仑造山带鄂拉山岩浆弧。研究成果为柴达木盆地北缘东部地区大地构造划分提供了新的数据资料支撑。 展开更多
关键词 拉合根 火山岩 锆石U-PB定年 HF同位素 构造环境
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西天山乌孙山花岗岩和闪长岩年代学、地球化学及岩石成因 被引量:1
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作者 孙吉明 马中平 +1 位作者 贠杰 王国强 《西北地质》 CAS CSCD 北大核心 2024年第3期59-72,共14页
笔者选取位于伊犁盆地内乌孙山北缘察布查尔林场花岗岩为研究对象,其地球化学、地质年代学和岩石成因研究对于探讨西天山南缘壳幔岩浆作用具有较重要的指示意义。岩石地球化学特征显示二长花岗岩属高钾钙碱性准铝质-弱过铝质岩石系列;... 笔者选取位于伊犁盆地内乌孙山北缘察布查尔林场花岗岩为研究对象,其地球化学、地质年代学和岩石成因研究对于探讨西天山南缘壳幔岩浆作用具有较重要的指示意义。岩石地球化学特征显示二长花岗岩属高钾钙碱性准铝质-弱过铝质岩石系列;轻稀土富集,弱的Eu负异常(δEu=0.74~0.84),富集大离子亲石元素,亏损Nb、Ta、P、Ti等高场强元素特征,Zr/Hf=42~44,部分样品中含有少量的刚玉标准矿物,显示出壳源花岗岩的特征。闪长岩Al_(2)O_(3)、FeOT、CaO含量明显高于二长花岗岩,Na_(2)O和K_(2)O含量低于二长花岗岩,属于高钾准铝质岩石系列;轻稀土富集,显示出Eu的轻微正异常(δEu=0.90~1.24),富集大离子亲石元素,亏损Nb、Ta等高场强元素,此外,闪长岩还显示出具有高Sr(Sr>400×10^(-6))低Y(12.83×10^(-6))及Yb(1.34×10^(-6))和高Mg^(#)特征,其源岩应为俯冲板片上覆地幔部分熔融产物。二者均显示出岛弧岩浆的特征。二长花岗岩锆石U-Pb年龄为(361.7±1.8)Ma;形成于晚泥盆世末期,结合前人的研究资料认为在~360 Ma由于南天山洋板片的回撤或俯冲流体参与,上覆地幔发生部分熔融产生了基性岩浆,岩浆上涌过程中提供大量的热导致地壳发生部分熔融形成了酸性岩浆,两种岩浆发生不均匀混合作用。上涌的岩浆引起地幔对流,导致伊犁地块内部出现一定的伸展作用(弧后伸展作用)。 展开更多
关键词 西天山 花岗岩及包体 锆石U-PB定年 岩石地球化学 构造环境
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激光剥蚀-扇形磁场电感耦合等离子体质谱法同时测定锆石U-Pb年龄和微量元素含量 被引量:1
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作者 赵令浩 孙冬阳 +3 位作者 胡明月 袁继海 范晨子 詹秀春 《岩矿测试》 CAS CSCD 北大核心 2024年第1期47-62,共16页
激光剥蚀-扇形磁场电感耦合等离子体质谱(LA-SF-ICP-MS)具有高灵敏度特征,被广泛应用于锆石等含U矿物原位微区U-Pb定年研究,但磁偏转式质量分析器的使用导致该质谱仪扫描速度相对较慢,可能影响U-Pb同位素与其他关键微量元素的同时采集... 激光剥蚀-扇形磁场电感耦合等离子体质谱(LA-SF-ICP-MS)具有高灵敏度特征,被广泛应用于锆石等含U矿物原位微区U-Pb定年研究,但磁偏转式质量分析器的使用导致该质谱仪扫描速度相对较慢,可能影响U-Pb同位素与其他关键微量元素的同时采集。本文通过优化仪器信号稳定性和实验方法,对目前常用的7种锆石U-Pb标准样品进行U-Pb定年和Ti、REEs、Hf等关键元素同时定量分析,探讨了多元素同时分析方法的可行性及对于U-Pb定年结果的影响。实验结果表明,相对于LA-SF-ICP-MS仅检测U-Pb同位素方法,同时开展多元素含量检测可能会使U-Pb同位素信号强度稳定性下降,导致单点U-Pb年龄结果误差及离散程度增大。与仅测定U-Pb同位素年龄的测定结果相比较,根据不同锆石样品中U-Pb同位素含量高低,多元素同时检测获得分析点的206Pb/238U年龄和207Pb/235U年龄变化范围不同程度地增大,其中207Pb/235U年龄受影响明显,单点207Pb/235U年龄误差从~1.5%增大至~2.0%,单点年龄的相对标准偏差(RSD)从0.5%~1.3%增大至1.2%~3.3%。尽管如此,多元素同时检测方法对于各样品最终测定年龄没有明显的影响,相对于TIMS年龄,各样品的谐和年龄和206Pb/238U加权平均年龄偏差分别小于1.0%和0.7%,完全满足U-Pb同位素地质年代学测试要求。同时测定锆石样品中的关键微量元素含与其推荐值相对误差小于10%。因此,采用LA-SF-ICP-MS可以同时准确地测定锆石U-Pb年龄和微量元素含量,该方法亦可用于其他副矿物U-Pb年龄与关键微量元素同时测定。 展开更多
关键词 激光剥蚀-扇形磁场电感耦合等离子体质谱(LA-SF-ICP-MS) 锆石 U-PB定年 微量元素
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塔吉克斯坦南帕米尔阿里秋(Alichur)穹隆花岗岩锆石U-Pb定年、Hf同位素特征及地质意义
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作者 刘江 罗彦军 +1 位作者 范堡程 Mustafo Gadoev 《西北地质》 CAS CSCD 北大核心 2024年第6期290-299,共10页
南帕米尔地区分布一系列受拆离断层控制,于印度–欧亚大陆碰撞过程中形成的穹隆构造,穹隆核部以晚中生代花岗岩和高级变质岩为主,并有少量新生代花岗质侵入岩。为阐明穹隆有关花岗岩的侵位背景和构造意义,笔者通过LA-MC-ICP锆石U-Pb定... 南帕米尔地区分布一系列受拆离断层控制,于印度–欧亚大陆碰撞过程中形成的穹隆构造,穹隆核部以晚中生代花岗岩和高级变质岩为主,并有少量新生代花岗质侵入岩。为阐明穹隆有关花岗岩的侵位背景和构造意义,笔者通过LA-MC-ICP锆石U-Pb定年测试获得侵位到穹隆拆离断层韧性剪切带中的花岗岩和占穹隆体积主体的核部白垩纪花岗岩年龄,分别为(19.3±0.4)Ma和(111.7±0.8)Ma。结合帕米尔地区和南帕米尔穹隆构造已有研究成果,笔者认为锆石Hf同位素特征反映南帕米尔地区晚中生代花岗岩是含有亏损地壳熔融作用的结果。新生代花岗岩形成于构造减压导致的中下地壳部分熔融作用,宏观上可能形成于印度板块碰撞俯冲过程中的减速调整阶段。 展开更多
关键词 花岗岩 定年 帕米尔 塔吉克斯坦
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南岭湘南吴家坪锡矿成岩成矿时代研究
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作者 夏杰 卢友月 +6 位作者 付建明 张遵遵 程顺波 李剑锋 宁勇云 冯经平 张吉梼 《地质通报》 CAS CSCD 北大核心 2024年第4期572-581,共10页
南岭吴家坪锡矿为湖南大义山地区近年新发现的具有中型以上远景规模的云英岩型矿床,矿体呈脉状产于大义山复式花岗岩体内部,受NE向断裂控制。为确定其成岩、成矿时代,总结大义山地区成矿规律,指导区域找矿及勘查工作,对赋矿围岩中粗粒... 南岭吴家坪锡矿为湖南大义山地区近年新发现的具有中型以上远景规模的云英岩型矿床,矿体呈脉状产于大义山复式花岗岩体内部,受NE向断裂控制。为确定其成岩、成矿时代,总结大义山地区成矿规律,指导区域找矿及勘查工作,对赋矿围岩中粗粒斑状黑云母二长花岗岩(PM21-19)、中细粒斑状黑云母二长花岗岩(PM21-27)进行了LA−ICP−MS锆石U−Pb定年研究。测年结果表明,其成岩年龄为157.1±1.1 Ma(MSWD=0.55)和153.7±1.2 Ma(MSWD=0.55),属燕山早期。同时,获得云英岩型锡矿石中石英Rb−Sr等时线年龄为148.1±2.1 Ma(MSWD=0.52)。结合区域资料认为,吴家坪锡矿成岩成矿时代为燕山早期,属南岭地区中生代成岩成矿高峰期(160~150 Ma)的产物。 展开更多
关键词 锆石U−Pb年龄 石英Rb−Sr定年 锡矿床 吴家坪 南岭 矿产勘查工程
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播期对不同熟期组大豆品质的影响
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作者 孙旭刚 张立军 +2 位作者 李盛有 王文斌 曹永强 《大豆科学》 CAS CSCD 北大核心 2024年第3期352-358,共7页
为明确不同播期对大豆品质的影响,本研究以东北地区不同熟期组(早、中、晚)的20个大豆品种为试材,探讨了不同播期(5月13日、5月23日、6月2日、6月12日和6月22日)条件下大豆蛋白质含量、脂肪含量、蛋脂总量等品质指标的变化规律。结果表... 为明确不同播期对大豆品质的影响,本研究以东北地区不同熟期组(早、中、晚)的20个大豆品种为试材,探讨了不同播期(5月13日、5月23日、6月2日、6月12日和6月22日)条件下大豆蛋白质含量、脂肪含量、蛋脂总量等品质指标的变化规律。结果表明:整体而言,播期推迟在10 d以内,对大豆品质影响较小,推迟10~20 d,对蛋白质含量的影响大于对脂肪含量影响,推迟20 d以上,各项品质指标与第1期差异达到显著或极显著水平,推迟40 d时,蛋白质含量和脂肪含量均极显著下降,达到最低值。本研究进一步分析了不同熟期组大豆品质对播期推迟的响应。结果表明:大豆品质指标随播期推迟而变化的趋势与品种的生育日数(即熟期)密切相关,不同熟期组间存在较大差异,播期推迟越晚导致早熟组大豆平均蛋白质含量降低的幅度越大,第3期(6月2日)及以后各期蛋白质含量较第1期(5月13日)下降达到显著、极显著水平,中熟组和晚熟组大豆的蛋白质含量分别在6月2日和6月12日前,差异不显著;晚熟组大豆脂肪含量随播期推迟显著下降,且下降幅度逐渐扩大,早熟组和中熟组大豆的脂肪含量分别在6月2日和6月12日下降未达显著水平;不同熟期组的大豆蛋脂总量总体上随播期的推迟而下降,其下降趋势与蛋白质含量的变化规律基本一致,即早熟组大豆在晚播10 d以上时,蛋脂总量显著下降,而中熟组、晚熟组大豆蛋脂总量分别在6月12日和6月2日播种,蛋脂总量相对稳定;不同熟期组大豆晚播30 d以上时,各项品质指标均会出现严重下降。本研究为沈阳地区晚播大豆的品质预测提供重要参考依据。 展开更多
关键词 播期 大豆 熟期组 品质
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江西九岭南缘古阳寨地区铍矿化伟晶岩独居石U-Pb定年及其地质意义 被引量:1
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作者 徐喆 张福神 +6 位作者 张芳荣 张勇 周渝 徐进 黄成伟 贺彬 龙立学 《东华理工大学学报(自然科学版)》 CAS 北大核心 2024年第1期13-21,共9页
以江西九岭南缘古阳寨地区铍矿化伟晶岩为研究对象,选取规模较大的藏龙洞铍矿化伟晶岩脉,通过野外地质调查和LA-ICP-MS测定独居石U-Pb年龄测定,初步了解了九岭南缘古阳寨地区花岗伟晶岩地质特征。结果表明,九岭南缘古阳寨地区铍矿化伟... 以江西九岭南缘古阳寨地区铍矿化伟晶岩为研究对象,选取规模较大的藏龙洞铍矿化伟晶岩脉,通过野外地质调查和LA-ICP-MS测定独居石U-Pb年龄测定,初步了解了九岭南缘古阳寨地区花岗伟晶岩地质特征。结果表明,九岭南缘古阳寨地区铍矿化伟晶岩成岩成矿年龄为(138.57±0.78) Ma,归属于早白垩世。铍矿化伟晶岩侵入于九岭南缘古阳寨中细粒含斑二云母二长花岗岩体内部,形成时代略晚于燕山期古阳寨岩体,显示两者在空间和时间上具有密切的成因联系,推测古阳寨地区铍矿化伟晶岩为古阳寨岩体二云母二长花岗岩结晶分异而成。建议针对古阳寨二云母二长花岗岩体内部和外接触带0~5 km范围内,加强调查力度,以期实现该区域内伟晶岩型铍矿找矿突破。 展开更多
关键词 独居石U-Pb定年 铍矿化伟晶岩 古阳寨地区 九岭南缘
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