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Xue and Haoxue:Learning Contents and Learning Attitude in The Analects of Confucius
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作者 LIANG Kai 《Cultural and Religious Studies》 2024年第9期559-565,共7页
The Analects(Lunyu論語)is a fundamental text for understanding the teachings of Confucius and offers an extensive account of the importance and methodology of learning(xue學)in the quest to become a junzi(君子),or exe... The Analects(Lunyu論語)is a fundamental text for understanding the teachings of Confucius and offers an extensive account of the importance and methodology of learning(xue學)in the quest to become a junzi(君子),or exemplary person.This paper explores the contents and attitudes of learning as presented in The Analects,focusing on how Confucius’disciples and subsequent generations compiled and understood his teachings.Confucius emphasized that the ultimate goal of learning is to become a junzi.The term junzi originally referred to nobles or aristocrats but was redefined by Confucius to describe anyone who cultivates themselves to achieve moral excellence and serve society effectively.In The Analects,the concept of junzi is constructed through various entries that illustrate what a junzi should and should not do,highlighting attributes such as being highly principled,disciplined,ethical,and capable.Confucius outlined specific content areas for learning that were essential for personal and social development.These included learning cultural knowledge(學文),the Book of Changes(學易),the Book of Odes(學詩),the Book of Propriety(學禮),and the Way(學道).He believed that proper behavior,such as filial piety,respect for elders,trustworthiness,and benevolence,was a prerequisite for effective learning.Through the study of these classical texts,learners could cultivate their emotions,improve their observational abilities,and enhance their social skills.In addition to content,Confucius stressed the importance of having the right attitude towards learning.He valued the enjoyment of learning(好學)and praised those who pursued knowledge with diligence and an open mind.This attitude was exemplified by his favorite disciple,Yan Hui,who was noted for his ability to learn without repeating mistakes or transferring anger to others.Confucius himself also modeled this attitude,demonstrating a lifelong commitment to learning and self-improvement.In conclusion,The Analects presents learning as a holistic process that encompasses not only the acquisition of knowledge but also the development of moral and social virtues.Confucius’teachings emphasize that through persistent and disciplined learning,individuals can achieve personal growth and contribute positively to society,embodying the qualities of a true junzi. 展开更多
关键词 The Analects CONFUCIUS LEARNING exemplary man contents ATTITUDE
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Mechanical properties and acoustic emission characteristics of soft rock with different water contents under dynamic disturbance 被引量:1
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作者 Yujing Jiang Lugen Chen +4 位作者 Dong Wang Hengjie Luan Guangchao Zhang Ling Dong Bin Liang 《International Journal of Coal Science & Technology》 EI CAS CSCD 2024年第3期135-148,共14页
Uniaxial compression tests and cyclic loading acoustic emission tests were conducted on 20%,40%,60%,80%,dry and saturated muddy sandstone by using a creep impact loading system to investigate the mechanical properties... Uniaxial compression tests and cyclic loading acoustic emission tests were conducted on 20%,40%,60%,80%,dry and saturated muddy sandstone by using a creep impact loading system to investigate the mechanical properties and acoustic emission characteristics of soft rocks with different water contents under dynamic disturbance.The mechanical properties and acoustic emission characteristics of muddy sandstones at different water contents were analysed.Results of experimental studies show that water is a key factor in the mechanical properties of rocks,softening them,increasing their porosity,reducing their brittleness and increasing their plasticity.Under uniaxial compression,the macroscopic damage characteristics of the muddy sandstone change from mono-bevel shear damage and‘X’type conjugate bevel shear damage to a roadway bottom-drum type damage as the water content increases.Dynamic perturbation has a strengthening effect on the mechanical properties of samples with 60%and less water content,and a weakening effect on samples with 80%and more water content,but the weakening effect is not obvious.Macroscopic damage characteristics of dry samples remain unchanged,water samples from shear damage and tensile–shear composite damage gradually transformed into cleavage damage,until saturation transformation monoclinic shear damage.The evolution of acoustic emission energy and event number is mainly divided into four stages:loading stage(Ⅰ),dynamic loading stage(Ⅱ),yield failure stage(Ⅲ),and post-peak stage(Ⅳ),the acoustic emission characteristics of the stages were different for different water contents.The characteristic value of acoustic emission key point frequency gradually decreases,and the damage degree of the specimen increases,corresponding to low water content—high main frequency—low damage and high water content—low main frequency—high damage. 展开更多
关键词 Dynamic disturbance Soft rock Cyclic loading Acoustic emission Water content
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A Simulative Study on Effects of Climate Warming on Nutrient Contents and In Vitro Digestibility of Herbage Grown in Qinghai-Xizang Plateau 被引量:11
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作者 徐世晓 赵新全 +3 位作者 孙平 赵同标 赵伟 薛白 《Acta Botanica Sinica》 CSCD 2002年第11期1357-1364,共8页
The increasing trend of air temperature along with the climate warming has been accepted gradually by scientists and by the general public. Qinghai_Xizang Plateau, a unique geographic unit due to high_altitude climate... The increasing trend of air temperature along with the climate warming has been accepted gradually by scientists and by the general public. Qinghai_Xizang Plateau, a unique geographic unit due to high_altitude climate, is one of the most susceptible regions to climate warming. Its ecosystem is very fragile and sensitive to climate change. In order to get a better understanding of the impacts of climate warming on the nutrient contents of herbage grown in Qinghai_Xizang Plateau, a simulative study was implemented at Daban Moutain by using temperature differences resulted from sites selected at different altitudes and nutrient contents and in vitro digestibility were determined for assessing the quality of the grown herbage. There were significant downtrends in crude protein (CP), ether extract (EE) and nitrogen free extract (NFE) contents of herbage along with the increase of temperature. It had a positive correlation between temperature and content of acid detergent fibre (ADF), acid detergent lignin (ADL) in herbage. In vitro digestibility of herbage decreased along with the increase of temperature. The results of this study indicated that climate warming significantly influence nutrient contents and in vitro digestibility of herbage grown in Qinghai_Xizang Plateau. It is suggested that the future climate warming especially the gradual rise of the night temperature could cause negative effect on herbage quality grown in Qinghai_Xizang Plateau by decreasing CP, EE, and NFE contents and increasing some indigestible ingredients such as crude fibre (CF), neutral detergent fibre (NDF), ADF, and ADL. This, consequently, decreases the ruminant assimilation ability. 展开更多
关键词 climate warming Daban Mountain temperature HERBAGE nutrient contents in vitro digestibility
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Optimization of Extraction Process for Total Flavonoids from Penthorum chinense Pursh and Comparison of Their Contents from Different Parts
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作者 Hongsheng LIU Jiqiang YAO +2 位作者 Xue BAI Jianying KANG Yefei YUAN 《Medicinal Plant》 2024年第2期10-14,共5页
[Objectives]This study was conducted to optimize the extraction process of total flavonoids from Penthorum chinense Pursh and compare their contents from different parts.[Methods]Single factor and orthogonal experimen... [Objectives]This study was conducted to optimize the extraction process of total flavonoids from Penthorum chinense Pursh and compare their contents from different parts.[Methods]Single factor and orthogonal experiments were designed to optimize the extraction process of total flavonoids from P.chinense Pursh with the volume fraction of ethanol,the ratio of material to liquid,heating reflux extraction time and extraction times as factors,and the content of total flavonoids as the index.A verification test was carried out.The optimized extraction process was adopted to compare the contents of total flavonoids from different parts of P.chinense Pursh.[Results]The best extraction process was extracting the powder of P.chinense Pursh for 2.0 h with 20 times of 55%ethanol by reflux twice.Under this condition,the contents of total flavonoids were 3.63%,8.90%,11.28%,and 4.36%from stems,leaves,flowers and whole grass of P.chinense Pursh,respectively.[Conclusions]The process is reasonable,feasible and stable,and can effectively extract total flavonoids from P.chinense Pursh.The contents of total flavonoids from different parts of P.chinense Pursh were quite different,and the value was higher in the leaves and flowers,so the proportions of leaves and flowers should be paid attention to in the industrial processing of P.chinense Pursh. 展开更多
关键词 Penthorum chinense Pursh Total flavonoids Orthogonal experiments Extraction process Content determination
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基于ISI Current Contents Connect的学科网站研究——以气象学为例 被引量:1
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作者 朱紫阳 张艳 顾建新 《图书情报知识》 CSSCI 北大核心 2008年第5期62-66,共5页
本文从专家推荐网站入手对学科网站进行研究,以气象学为例,通过检索ISI Current Contents Connect数据库,对学科网站的地理分布、语种分布、信息来源、出版者及关键词进行统计分析,总结出学科网站的一些特点。最后对目前学科网络信息资... 本文从专家推荐网站入手对学科网站进行研究,以气象学为例,通过检索ISI Current Contents Connect数据库,对学科网站的地理分布、语种分布、信息来源、出版者及关键词进行统计分析,总结出学科网站的一些特点。最后对目前学科网络信息资源研究提出了自己的看法。 展开更多
关键词 ISI CURRENT contents Connect气象学 学科网站
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Responses of Photosynthetic Pigment, Phenol and Total Saponin Contents of Panax notoginseng to Supplemental UV-B under Field Conditions
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作者 赵昶灵 陈中坚 +4 位作者 魏富刚 李孙文 杨莉 李俊 王崇德 《Agricultural Science & Technology》 CAS 2014年第7期1120-1124,1151,共6页
[Objective] The aim of this study was to investigate the content changes and their correlations of the photosynthetic pigment,phenols,including total phenols,total flavonoids and anthocyanins,and total saponins of the... [Objective] The aim of this study was to investigate the content changes and their correlations of the photosynthetic pigment,phenols,including total phenols,total flavonoids and anthocyanins,and total saponins of the one-year-old P.notoginseng plants under supplemental UV-B stress in fields.[Method] The one-year-old plants were irradiated by UV-B in field for 1 min per day,and the plants under the UV-B lamp were regarded as a circle center,achieving an annular leaf-sampling.The photosynthetic pigment,phenols and total saponins of the leaves were determined spectrophotometrically.[Result] With the increase of sampling radius,the supplemental UV-B intensity decreased significantly,the contents of chlorophyll (Chl) a,Chl b,Chl (a+b),carotenoid (Car) and total photosynthetic pigment (Chl+Car) of the leaves increased extremely significantly,the Chl a/b and total phenol content (TPC) decreased extremely significantly,but the Chl (a+b)/Car changes were not significant.The contents of total flavonoids,anthocyanins and saponins all increased due to the increasing of UV-B,displaying dose effects.The UV-B intensity was positively correlated with the Chl a/b,and negatively with the Chl a,Chl b,Chl (a+ b),Car and (Chl+Car) contents; and the two of TPC,total flavonoid content (TFC),total anthocyanin content (TAC) and total saponin content (TSC) were positively correlated,all reaching extremely significant level.The UV-B intensity was positively and significantly correlated with the total flavonoid content (TFC),negatively and significantly with the Chl (a+b)/Car,and positively and insignificantly with the TPC,TAC and TSC.[Conclusion] For one-year-old plants of P.notoginseng,UV-B can decrease the contents of the Chl a,Chl b,Chl (a+b),Car and (Chl+Car) and increase the Chl a/b and TPC,and,furthermore,induce the increases of the TFC,TAC and TSC in a dose-dependent manner.However,UV-B can hardly change the Chl (a+b)/Car.The supplemental UV-B of well-suited dose might be one of the effective measures to improve the TSC of P.notoginseng. 展开更多
关键词 One-year-old Panax notoginseng plants Photosynthetic pigment Phenol and total saponin contents Supplemental UV-B Response
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Effects of Lead/Chromium Stress on Contents of Chlorophyll in Bryum argenteum and Barbula indica
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作者 汪琛颖 《Agricultural Science & Technology》 CAS 2013年第11期1587-1590,共4页
[Objective] This study aimed to clarify the effects of Pb2+ and Cr3+ stress on the contents of chlorophyl in Bryum argenteum and Barbula indica. [Method] B. ar-genteum and B. indica were cultured in different concen... [Objective] This study aimed to clarify the effects of Pb2+ and Cr3+ stress on the contents of chlorophyl in Bryum argenteum and Barbula indica. [Method] B. ar-genteum and B. indica were cultured in different concentrations of lead nitrate solu-tion or chromium chloride solution, to investigate the changes in contents of photo-synthetic pigments under lead and chromium single stress. [Result] The results showed that the effects of 1, 10 and 200 mg/L Pb2+ on B. indica were greater than those on B. argenteum; the effects of 1, 50, 100 and 200 mg/L Cr3+ on B. argen-teum were greater than those on B. indica. Total chlorophyl content in B. argen-teum and B. indica under different concentrations of Pb2+ and Cr3+ was decreased compared with that in control. The tolerance of B. indica to Pb2+ pol ution was lower than that of B. argenteum, while the tolerance of B. indica to Cr3+ pol ution was greater than that of B. argenteum. [Conclusion] Based on the conventional require-ments for monitoring materials, B. indica can be used as an indicator species to monitor heavy metal pol ution in the atmosphere of Zhengzhou. 展开更多
关键词 Bryum argenteum Barbula indica Pb2* CRY+ Heavy metal pollution Chlorophyll contents
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Assessment criteria for nonverbal interaction contents in r-learning
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作者 CHOI Jong-hong LEE Jong-yun YOON Heung-seob 《Journal of Central South University》 SCIE EI CAS 2013年第9期2388-2398,共11页
r-learning,which is based on e-learning and u-learning,is defined as a learning support system that intelligent robots serve verbal and nonverbal interactions on ubiquitous computing environment.In order to guarantee ... r-learning,which is based on e-learning and u-learning,is defined as a learning support system that intelligent robots serve verbal and nonverbal interactions on ubiquitous computing environment.In order to guarantee the advantages of r-learning contents with no limits of timc and place and with nonverbal interaction which are not in e-learning contents,in recent years,assessment criteria for r-learning contents are urgently rcquired.Therefore,the reliable and valid assessment criteria were developed for nonverbal interaction contents in r-learning,and its detailed research content is as follows.First,assessment criteria for nonverbal interaction in r-learning contents will be specified into gesture,facial expression,semi-verbal message,distance,physical contact and time.Second,the validity of the developed assessment criteria will be proved by statistics.Consequently,the assessment criteria for nonverbal interaction contents will be helpful when choosing the better r-learning content and producing the better r-learning content,and the reliability of school education is improved ultimately. 展开更多
关键词 r-learning r-learning contents assessment criteria nonverbal interaction contents confirmatory factor analysis construct validity
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Comparative Study on Phosphorus Contents of Soil in Karst Rocky Desertification Area during Eco-restoration Process in Guangxi Province 被引量:15
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作者 覃勇荣 刘旭辉 +2 位作者 曾忠良 周春梅 蓝崇钰 《Agricultural Science & Technology》 CAS 2008年第3期141-144,共4页
[Objective] The research aimed to study change law of phosphorus content of soil in karst rocky desertification region(KRD) during eco-restoration process such as Northwest Guangxi Province.[Method] The soil samples w... [Objective] The research aimed to study change law of phosphorus content of soil in karst rocky desertification region(KRD) during eco-restoration process such as Northwest Guangxi Province.[Method] The soil samples were collected from typical KRD in Pingguo County and Yizhou City.The determining quotas of different soil samples such as soil total phosphorus content and available phosphorus content were detected,in addition the soil total phosphorus content,available phosphorus content, urease activity, catalase activity and organic matter content in different soil samples were analyzed comparatively.[Result] Aspect,vegetation type and recovery time generated obviously influences on phosphorus contents in different soil samples.The concrete influence order was listed as follow: phosphorus content in soil of south slope was higher than that in soil of north slope;phosphorus content in soil where Zenia insignis Chun was planted was higher than that in soil of closed forest and that of soil where Dendrocalamus minor Var. amoen was planted,additionally,phosphorus increased with recovery time. Urease activity could be used as a monitoring index of soil fertility because it is related to the change of phosphorus content.[Conclusion] The soil of karst rocky desertification region in Northwest Guangxi Province could be recovered gradually if excessive human disturbance was stopped.If proper natural method of recovery promoted by human was taken,the recovery would reach a better result. 展开更多
关键词 PHOSPHORUS content in SOIL KARST rocky DESERTIFICATION Eco-restoration
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Responses of the Anthocyanin and Osmolyte Contents of the Capsicum annuum Cultivars Planted in Wenshan Prefecture of Yunnan Province to the Drought Stress Simulated by PEG-6000 被引量:3
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作者 李云 孟凡来 +6 位作者 赵昶灵 屈用函 袁恩平 杨羚钰 张雪廷 王绍祥 赵水灵 《Agricultural Science & Technology》 CAS 2016年第6期1295-1300,1335,共7页
[Objective] The aim of this study was to compare the drought resistance difference of the main Capsicum annuum cultivars planted in Wenshan Prefecture of Yunnan Province. [Method] The total anthocyanin, soluble sugar,... [Objective] The aim of this study was to compare the drought resistance difference of the main Capsicum annuum cultivars planted in Wenshan Prefecture of Yunnan Province. [Method] The total anthocyanin, soluble sugar, soluble protein and free proline contents of the leaves of the five main C. annuum cultivars planted in Wenshan Prefecture, i.e., ZSZ75-1, ZSZ49-1-1, 12WS-18-1, 12ZH01 and ZS130, under the drought stress simulated by PEG-6000 were studied by using spectrophotometry, and the total osmoregulation abilities of the leaves were evaluated by using subordinate function. [Result] Under the drought stress simulated by PEG-6000, the total anthocyanin contents of the veins, mesophylls and whole leaves of the five cultivars were all as: ZSZ75-1〉ZSZ49-1-1〉12WS-18-1〉12ZH01〉ZS130, the soluble sugar contents as: 12ZH01 〉12WS-18-1 〉ZS130〉ZSZ49-1-1 〉ZSZ75-1, the soluble protein contents as: ZSZ75-1〉12ZH01〉ZSZ49-1-1〉12WS-18-1〉ZS130, and the free proline contents as: ZS130〉ZSZ75-1 〉12WS-18-1 〉ZSZ49-1-1 〉12ZH01. Furthermore, the differences among the total anthocyanin contents of the veins, mesophylls and whole leaves of the five cultivars all reached the extremely significant levels, whereas the differences among the contents of the soluble sugar, soluble protein and free proline did not reach the significant levels, the correlation degrees among the contents of the total anthocyanin, soluble sugar, soluble protein and free proline of different cultivars were also inconsistent, and the total osmoregulation abilities of the five cultivar leaves were as: ZSZ75-1 〉7SZ49-1-1 〉12WS-18-1 〉ZS130〉12ZH01. [Conclusion] The anthocyanin accumulation in the specific organs of the five C. annuum cultivars in Wenshan Prefecture is beneficial to the strengthening of the leaf osmoregulation abilities under drought stress, favoring the drought tolerance of the cultivars. 展开更多
关键词 Main Capsicum annuum cultivars planted in Wenshan Prefecture of Yunnan Province Anthocyanin content Osmolyte contents Drought stress simulated by PEG-6000 Response
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Effects of Land Use Patterns on Soil Heavy Metal Contents 被引量:23
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作者 孙亚乔 钱会 +1 位作者 段磊 杨胜科 《Agricultural Science & Technology》 CAS 2010年第1期159-162,共4页
Through sampling in farmland and analysis in laboratory,the contents and the pollution level of Cr,Cu,As,Pb,Zn in different soils were studied. The comparative result showed that the As in all soil samples are lower t... Through sampling in farmland and analysis in laboratory,the contents and the pollution level of Cr,Cu,As,Pb,Zn in different soils were studied. The comparative result showed that the As in all soil samples are lower than the mean value of Shaanxi and whole nation,the Cr in lower half soil samples are higher than the mean value of Shaanxi and whole nation,the Cu and Zn in majority soil samples are higher than the mean value of Shaanxi and whole nation,and the Pb in all soil samples is higher than the mean value of Shaanxi and whole nation. The single factor pollution index and multi-factor pollution index method were used to evaluate the soil pollution. According to Soil Environmental Quality Standard,the studied soils were at unpolluted degrees,the soils were clear,the quality of soil adapt to the crop growth,and not affect the quality of agricultural product. 展开更多
关键词 Farmland soil Heavy metal Content characteristics Qinling piedmont
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Effect of Nitrogen Application on Contents of Different Forms of Nitrogen in Rice Plants 被引量:9
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作者 莫润秀 江立庚 +6 位作者 郭立 胡均铭 刘开强 周佳民 梁天锋 曾可 丁成泉 《Agricultural Science & Technology》 CAS 2011年第10期1484-1489,共6页
[Objective]The paper was to study the effect of different nitrogen application levels and modes on contents of different forms of nitrogen in rice plants.[Method] Using Guichao 2 and Diejiazhan as test materials,with ... [Objective]The paper was to study the effect of different nitrogen application levels and modes on contents of different forms of nitrogen in rice plants.[Method] Using Guichao 2 and Diejiazhan as test materials,with total nitrogen,protein nitrogen,chlorophyll nitrogen,soluble protein nitrogen,Rubisco nitrogen,free amino acid nitrogen as indicators,the effect of nitrogen application on contents of different forms of nitrogen in rice plants were studied.[Result] The contents of total nitrogen,protein nitrogen,chlorophyll nitrogen,soluble protein nitrogen,Rubisco-N,free amino nitrogen of rice plant during heading and maturity stage increased with the increasing application amount of nitrogen,and their contents would be high under heavy application of spike fertilizer when the application amount of nitrogen was the same.However,application of nitrogen had different impact on different forms of nitrogen,which showed obvious impact on the contents of Rubisco-N and free amino nitrogen.The differences of Rubisco-N and free amino nitrogen content of two varieties during heading and maturity stage under different nitrogen application modes all reached significant or extremely significant level.Correlation analysis showed that total nitrogen content of rice plant had extremely significant correlation with protein nitrogen content during heading and maturity stage in both early and late seasons.[Conclusion] The study provided a theoretical basis for clarifying the regulatory role of nitrogen application on nitrogen absorption and utilization. 展开更多
关键词 Rice(Oryza sativa L.) Nitrogen content Nitrogen application Nitrogen forms
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Effects of Curing Techniques on Starch Contents of Leaves in Different Tobacco Parts with Varying Maturity Degrees 被引量:4
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作者 崔国民 汪伯军 +4 位作者 许安定 陈益银 杨超 罗以贵 韩善红 《Agricultural Science & Technology》 CAS 2014年第3期488-492,共5页
[Objective] The aim was to explore effects of different curing techniques on starch contents of tobaccos from different growth parts and with varying maturity degrees in order to reduce starch content of Yunnan tobacc... [Objective] The aim was to explore effects of different curing techniques on starch contents of tobaccos from different growth parts and with varying maturity degrees in order to reduce starch content of Yunnan tobacco. [Method] Compar- isons were conducted on tobaccos from upper, middle and down parts (immature, premature, mature and excessive mature) by low temperature and low humidity cur- ing technique, moderate temperature and moderate humidity curing technique, mod- erate temperature and high humidity curing technique to measure starch contents before and after curing. [Result] The results showed starch content of tobacco was increasing upon growth part. Low temperature and low humidity curing technique has poor effects on reduction of starch content; moderate temperature and moderate humidity curing technique improves starch content; moderate temperature and high humidity curing technique dramatically reduces starch content of tobaccos. [Conclu- sion] With consideration of tobacco appearance, inner quality and characters, moder- ate temperature and moderate humidity curing technique is recommended for tobac- co production. 展开更多
关键词 Tobacco leaf Flue-curing technique Starch content
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Investigation of Heavy Metal Contents in Traditional Chinese Herbal Medicine Peristrophe roxburghiana Collected from Northwest of Guangxi 被引量:2
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作者 刘旭辉 李容 +2 位作者 郭俊 罗志勇 覃勇荣 《Agricultural Science & Technology》 CAS 2016年第12期2751-2756,2762,共7页
Objective] This study was conducted to evaluate the product quality and safety of Peristrophe roxburghiana_ col ected from different places in Hechi City, northwest of Gunagxi, so as to provide basic data for further ... Objective] This study was conducted to evaluate the product quality and safety of Peristrophe roxburghiana_ col ected from different places in Hechi City, northwest of Gunagxi, so as to provide basic data for further development and uti-lization of the characteristic plant resource P. roxburghiana. [Method] Contents of 9 kinds of heavy metals including Cd, Mn, Pb, Zn and Cu in the herb were deter-mined by the method of wet digestion-flame atomic absorption spectrophotometry and atomic fluorescence spectrometry, respectively. [Results] Heavy metal contents of Cd, Mn, Pb, Fe, Cu, Zn, As, Hg and Se were 1.62-17.25, 8.93-142.53, 4.37-18.43, 103.7-242.81, 2.55-5.35, 85.40-146.30, 0.07-0.54, 0.00-0.08 and 0.00-0.47 mg/kg, respectively. According to the national food safety standards and Green Trade Standards of lmporting &amp; Exporting Medicinal plants &amp; Preparations, the heavy metal contents of the P. roxburghiana_samples col ected from different coun-ties in Hechi City exceeded standards or at the critical values. Among which, Cd, Pb and Zn contents of the samples are seriously higher than the standards. [Con-clusion] Therefore, the impact of soil heavy metal pol ution on the safety of edible plants in the northwest of Guangxi should be highly concerned. 展开更多
关键词 Northwest of Guangxi Traditional Chinese herbal medicine Peristro-pheroxburghiana Product quality and safety Heavy metal content
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Negative Effects of Oxytetracycline on Wheat (Triticum aestivum L.) Growth, Root Activity, Photosynthesis, and Chlorophyll Contents 被引量:10
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作者 LI Zhao-jun XIE Xiao-yu ZHANG Shu-qing LIANG Yong-chao 《Agricultural Sciences in China》 CAS CSCD 2011年第10期1545-1553,共9页
A solution culture experiment was performed to investigate the effects of oxytetracycline (OTC) on wheat (Triticum aestivum L.) growth, chlorophyll contents, and photosynthesis at five levels of 0, 10, 20, 40, and... A solution culture experiment was performed to investigate the effects of oxytetracycline (OTC) on wheat (Triticum aestivum L.) growth, chlorophyll contents, and photosynthesis at five levels of 0, 10, 20, 40, and 80 mmol L-1 OTC. OTC is toxic to wheat. The wheat growth, especially wheat root was significantly decreased. Further OTC also significantly decreased root activity, chlorophyll contents, and photosynthetic parameters except for intercellular CO2 concentrations. The different responses of indicators such as root number, root activity and so on to OTC were also observed. The IC50 values for the tested indicators to OTC ranged from 7.1 to 113.4 mmol L-1 OTC. The order of indicator sensitivity to OTC was root number stomatal conductance chlorophyll a total chlorophyll photosynthetic rates total surface area transpiration rate chlorophyll b fresh weight of root dry weight of root total length dry weight of shoot = fresh weight of shoot total volume. The root number was more sensitive than other indicators with the IC50 value of 7.1 mmol L-1 OTC, and could be taken as the sensitive indicator to predict the hazards of OTC to wheat. 展开更多
关键词 OTC WHEAT GROWTH root morphological characteristics chlorophyll contents PHOTOSYNTHESIS
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Correlation Between Chemical Element Contents in Tree Rings and Soils 被引量:8
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作者 QIANJUN-LONG KESHAN-ZHE 《Pedosphere》 SCIE CAS CSCD 1993年第4期309-319,共11页
The annual growth rings of ten trees and the soils near the tree roots were sampled from the mining area of lead-and zinc-dominant metals in the Xixia Mountain, Nanjing, for the determination of chemical element conte... The annual growth rings of ten trees and the soils near the tree roots were sampled from the mining area of lead-and zinc-dominant metals in the Xixia Mountain, Nanjing, for the determination of chemical element contents. The study results showed that the elemental contents in the tree rings were correlated with those in the soils, i. e., the elemental contents in the tree rings increased with those in the soils, even in the cases of different environments and different tree species. Therefore, a time-concentration sequence could be set up on the basis of determining the elemental contents in the successive annual growth rings of trees to qualitatively reflect the annual variations of relevant elements in the soils, and a time-concentration sequence of elemental contents in soils could also be established in terms of related model to reproduce the dynamic changes of the surroundings. 展开更多
关键词 CORRELATION elemental contents SOILS tree rings
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Characteristics of Fluoride Contents in Plants and Soils in Kaili City Under Air Pollution 被引量:1
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作者 杨成 罗绪强 +2 位作者 王娅 贺华中 黄亮 《Agricultural Science & Technology》 CAS 2012年第10期2129-2132,共4页
Fluoride contents in plants and soils in Kaili City were measured with fluorinion as per electrode method and the related characteristics were analyzed in order to explore effects of air fluoride pollution on plant an... Fluoride contents in plants and soils in Kaili City were measured with fluorinion as per electrode method and the related characteristics were analyzed in order to explore effects of air fluoride pollution on plant and soil.The results indicated that fluoride content in plants tended to be volatile in 135.62-1 420.97 μg/g and averaged 513.99 μg/g;fluoride content in soils changed from 240.50-340.36 μg/g and averaged 279.60 μg/g.The contents of plant and soil both exceeded background value,suggesting that plants and soils in the region have been polluted.In addition,fluoride contents differ significantly upon plants.In detail,the maximal content was in Camelliaolelfera Abel and the minimal in Camelliaolelfera Abel.The contents of fluoride in different plant species vary,as follows:shrub vine herbaceous plant arbor;evergreen plants deciduous plant;fluoride contents in plants and soils also differ in varying degrees upon research sites. 展开更多
关键词 Fluoride content Air pollution PLANT Soil Kaili
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Sugar beet yield and industrial sugar contents improved by potassium fertilization under scarce and adequate moisture conditions 被引量:5
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作者 Muhammad Umair Mubarak Muhammad Zahir +1 位作者 Sagheer Ahmad Abdul Wakeel 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2016年第11期2620-2626,共7页
Sugar beet(Beta vulgaris L.) is an industrial crop, grown worldwide for sugar production. In Pakistan, sugar is mostly extracted from sugarcane, soil and environmental conditions are equally favorable for sugar beet... Sugar beet(Beta vulgaris L.) is an industrial crop, grown worldwide for sugar production. In Pakistan, sugar is mostly extracted from sugarcane, soil and environmental conditions are equally favorable for sugar beet cultivation. Beet sugar contents are higher than sugarcane sugar contents, which can be further increased by potassium(K) fertilization. Total K concentration is higher in Pakistani soils developed from mica minerals, but it does not represent plant available K for sustainable plant growth. A pot experiment was conducted in the wire-house of Institute of Soil and Environmental Sciences at University of Agriculture Faisalabad, Pakistan. K treatments were the following: no K(K_0), K application at 148 kg ha^(–1)(K_1) and 296 kg ha^(–1)(K_2). Irrigation levels were used as water sufficient at 60% water holding capacity and water deficient at 40% water holding capacity. The growth, yield and beet quality data were analyzed statistically using LSD. The results revealed that increase in the level of K fertilization at water sufficient level significantly increased plant growth, beet yield and industrial beet sugar content. The response of K fertilization under water deficient condition was also similar, however overall sugar production was less than that in water sufficient conditions. It is concluded from this study that K application could be used not only to enhance plant growth and beet yield but also enhance beet sugar content both under water-deficient as well as water-sufficient conditions. 展开更多
关键词 POTASSIUM irrigation levels beet yields sugar contents
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Available Contents of Trace Nutrient Element and Factors Affecting Their Availability in Western Jilin 被引量:4
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作者 施宪 王冬艳 +2 位作者 李月芬 靳克 郭珍 《Agricultural Science & Technology》 CAS 2010年第5期73-76,共4页
Based on the assay of the total content and available content of the trace nutrient elements and the soil pH and organic matter of the soil samples,the characteristic of the available content of the trace nutrient ele... Based on the assay of the total content and available content of the trace nutrient elements and the soil pH and organic matter of the soil samples,the characteristic of the available content of the trace nutrient elements and their affecting factors are studied. The results show that the available B in western Jilin is in a middle level,the content in Nong'an is higher than that in the others; the available Mn is extremely abundant; the available Cu in Nong'an is obviously higher than other areas,and the content in Da'an differs greatly; the available Zn is in a middle level; the severe shortage of available Mo differs between different areas; and the available Fe is extremely abundant. The available Mn,Cu and Fe have significantly positive correlation with their total content; the available B has significantly positive correlation with pH,and Zn has obviously negative correlation with pH; the available Mn and Fe had significantly positive correlation with soil organic matter. 展开更多
关键词 Trace nutrient element Available content The affecting factors Western Jilin
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REE Contents in Topsoil on the Loess Plateau and Effects of REE Applying on Crops 被引量:5
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作者 刘普灵 田均良 +1 位作者 李雅奇 琚彤军 《Journal of Rare Earths》 SCIE EI CAS CSCD 1995年第3期221-224,共4页
Eight rare earth elements(REE) in 104 topsoil samples collected from the Loess Plateau has been determined by using of INAA. The regional distribution of REE contents and its effectiveness of REE applying on crops in ... Eight rare earth elements(REE) in 104 topsoil samples collected from the Loess Plateau has been determined by using of INAA. The regional distribution of REE contents and its effectiveness of REE applying on crops in this area are discussed. The preliminary results showed that the mean concentration of most REE in this area approaches to those of China as a whole; and REE content in main type of soil of the Loess Plateau is as follows: gray cinnamon forest soil, Lou soil(stratified old manured loessal soil)> Heilu soil(dark loessal soil) . loessal soil>sierozem, and similar with the distribution pattern of soil clay contents in the soil which decrease gradually from southeast to northwest. This area may be suitable to apply REE in agriculture production. 展开更多
关键词 Rare earth elements contents Application in agriculture Loess Plateau
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