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Dynamic Development Characteristics and Driving Factors of High Quality Development Level in China’s Five Major Urban Agglomerations
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作者 ZOU Weiyong XU Lingli 《Chinese Geographical Science》 SCIE CSCD 2024年第5期777-790,共14页
High-quality development is the primary task of comprehensively building a socialist,modern country,as well as the primary task of building urban agglomerations in China.Based on the five development concepts,this pap... High-quality development is the primary task of comprehensively building a socialist,modern country,as well as the primary task of building urban agglomerations in China.Based on the five development concepts,this paper used the entropy method to measure the High Quality Development Index(HQDI)of the five major urban agglomerations.The results showed that the HQDI of the five major urban agglomerations shows a fluctuating upward trend.First,using the Dagum Gini coefficient to explore the sources of HQDI development differences in urban agglomerations,we found that the main source of HQDI differences in urban agglomerations was inter-regional differences,while intra-regional differences were not important.Second,kernel density estimation was used to test the dynamic evolution trend of HQDI within urban agglomerations.There was a polarisation phenomenon in the HQDI of urban agglomerations,such as the Pearl River Delta urban agglomeration and the Chengdu-Chongqing urban agglomeration.But overall,the degree of imbalance had decreased.Third,using geographic detectors to examine the driving factors of HQDI in urban agglomerations,we found that the main driving forces for improving HQDI in urban agglomerations were economic growth,artificial intelligence technology and fiscal decentralisation.All the interaction factors had greater explanatory power for the spatial differentiation of HQDI,which can be divided into two types:two-factor improvement and non-linear improvement.This study is conducive to improving and enriching the theoretical system for evaluating the high quality development of urban agglomerations,and provides policy references for promoting the high quality development of urban agglomerations. 展开更多
关键词 urban agglomeration high quality Development Index(HQDI) spatio-temporal evolution driving factors
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Yield Characteristics of a New High-quality Disease-resistant Wheat Variety Chuanmai 618
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作者 Jianmin ZHENG Zongjun PU +4 位作者 Jijuan LU Jiangtao LUO Qingyan DENG Peixun LIU Shizhao LI 《Plant Diseases and Pests》 2024年第2期22-26,31,共6页
[Objectives]The paper was to analyze the yield characteristics of a new high-quality disease-resistant wheat variety Chuanmai 618.[Methods]The yield characteristics of Chuanmai 618 were analyzed using the AMMI model a... [Objectives]The paper was to analyze the yield characteristics of a new high-quality disease-resistant wheat variety Chuanmai 618.[Methods]The yield characteristics of Chuanmai 618 were analyzed using the AMMI model and GGE biplot based on data from a 2-year regional test and a 1-year production test.[Results]The analysis of the AMMI model for the 2-year regional test indicated that Chuanmai 618 had a moderate yield and good stability.During the production test,Chuanmai 618 had an average yield of 450.52 kg/666.7 m^(2),an effective spike of 235700 spike/666.7 m^(2),a 1000-seed weight of 47.93 g,and a kernel number per spike of 47.28.The AMMI analysis sequencing graph showed that the varieties were ranked in the following order:Zhongkemai 1816>Chuanmai 618>Shumai 1958>Chuanyu 42>Mianmai 367>Xikemai 5518.According to the GE analysis,Chuanmai 618 had comparative advantages.[Conclusions]The new wheat variety Chuanmai 618 is a high-quality disease-resistant variety with good yield and stability. 展开更多
关键词 Chuanmai 618 high quality Disease-resistant AMMI model high yield STABILITY
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Does green finance drive high-quality economic development?-Based on empirical evidence from China
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作者 WANG Shuang ZHANG Kai-lin LIU Xiang-yu 《Ecological Economy》 2024年第3期249-264,共16页
Green finance,as an important branch of modern finance,has far-reaching significance that is not limited to the financial sector.By promoting green investment and optimizing resource allocation,green finance plays a c... Green finance,as an important branch of modern finance,has far-reaching significance that is not limited to the financial sector.By promoting green investment and optimizing resource allocation,green finance plays a crucial role in reducing environmental pollution and carbon emissions.At the same time,it can also promote the quality of economic growth and achieve the harmonious development of economy,society and environment.Based on China's provincial panel data from 2008 to 2022,the direct impact and indirect transmission mechanism of green finance on high-quality economic development are analyzed by constructing a dynamic panel model and a mediation effect model.It is found that green finance not only directly promotes the high-quality development of the economy,but also indirectly promotes the sustainable and healthy growth of the economy through the transmission channel of technological innovation.This mediating effect of technological innovation is as high as 78.65%,which shows the close connection between green finance and high-quality economic development.In addition,the study also found that the direct promotion effect of green finance on high-quality economic development has significant regional heterogeneity.The results of this study suggest that when formulating relevant policies,it is necessary to fully consider the actual situation of each region and tailor them to the local conditions to ensure the in-depth promotion of green finance and the overall development of the economy. 展开更多
关键词 green finance high quality economic development system GMM mediating effect
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Six-Dimensional Guidance: The Strategies of Thinking Quality Cultivation in Senior High School English Discourse Learning
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作者 Junjie Sun 《Journal of Contemporary Educational Research》 2024年第3期237-245,共9页
Taking the discourse learning of the new senior high school English textbook published by the People’s Education Press as an example,combined with the“six-dimensional guidance”deep reading strategy,and through the ... Taking the discourse learning of the new senior high school English textbook published by the People’s Education Press as an example,combined with the“six-dimensional guidance”deep reading strategy,and through the six-skill training strategies of“memory skill training,understanding skill training,application skill training,analytical skill training,evaluation skill training,creative skill training,”this paper aims to cultivate students’thinking profundity,logic,flexibility,sensitivity,criticality,and originality.It also promotes the real implementation of senior high school English deep reading that points to the cultivation of thinking quality in classroom teaching,and realizes the transformation from“conventional reading”to“deep reading”that reflects the core literacy of the discipline. 展开更多
关键词 Six-dimensional guidance high school English Discourse learning Thinking quality Strategy
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Effects of Seed Rate on Root Twining Power and Seedling Quality of Machine-transplanted Super Rice 被引量:3
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作者 滕飞 朱德峰 +2 位作者 陈惠哲 蔡雪青 徐一成 《Agricultural Science & Technology》 CAS 2015年第12期2644-2648,2652,共6页
In order to investigate the effects of seed rate on root twining power and seedling quality of machine-transplanted super rice cultivars, Yongyou 12 and Zhongzheyou No.l, total 6 seed rates were arranged, and the grow... In order to investigate the effects of seed rate on root twining power and seedling quality of machine-transplanted super rice cultivars, Yongyou 12 and Zhongzheyou No.l, total 6 seed rates were arranged, and the growth characteris- tics, quality and root twining power of machine-transplanted rice seedlings were studied. The results showed that seed rate had great effects on root twining power and qualityof rice seedlings; with the increase of seed rate, the root twining power of rice seedlings was increased, but the quality of rice seedlings was significantly reduced; under the condition of high seed rate, rice seedlings were weak with less accumulate dry matter and nonuniform growth, and the proportion of weak seedlings was higher. When the seed rate of both rice cultivars was reduced by 10 g/tray, the average seedling height was increased by 0.5 cm, leaf age was increased by 0.1, stem base diameter was increased by 0.1 cm, and root number per plant was increased by 0.3. When the seed rate was increased by 10 g/tray, the accumulated dry matter per plant was reduced by 5.1 mg. With the increase of seed rate, the seedling quality of Zhongzheyou No.1 was decreased rapidly, and the proportion of weak seedlings was increased rapidly. However, Yongyou 12 has a larger elasticity in seed rate. When the seed rate reached to 50 g/tray, blanket seedlings of Yongy- ou 12 were nursed with uniform growth and higher quality, but the shoots were sparse with lower leaf area index. However, when the seed rate was up to 50 g/tray, blanket seedlings of Zhongzheyou No.1 were nursed with uniform growth and higher quality, as well as higher-density shoots. From a comprehensive point of view, the optimum seed rates of Yongyou 12 and Zhongzheyou No.1 were 65 and 50 g/tray, respectively. 展开更多
关键词 RICE Super rice Mechanical transplanting Seed rate Blanket seedling seedling quality
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Relation Analysis of Several Agronomic Traits and Single Plant Lint Yield in Upland Cotton with High Quality 被引量:8
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作者 汤飞宇 王晓芳 +1 位作者 莫旺成 肖文俊 《Agricultural Science & Technology》 CAS 2009年第2期90-92,共3页
[ Objective] The purpose was to study the correlation between main agronomic traits and single plant lint yield in upland cotton with high quality. [ Method] Twenty-four upland cotton lines with high quality were anal... [ Objective] The purpose was to study the correlation between main agronomic traits and single plant lint yield in upland cotton with high quality. [ Method] Twenty-four upland cotton lines with high quality were analyzed for single plant lint yield and 10 agronomic traits in a randomized, complete block at the agriculture experimental station of JXAU, Nanchang, China in 2007. They were divided into three types ( high, medium, low yield) based on single plant lint yield by Ward's method. A total of 11 traits of three types were compared. Correlation a- nalysis and stepwise regression analysis of 10 agronomic traits to single plant lint yield were carried out. [ Result] There existed statistically sig- nificant difference in bolls per plant, ~int percentage, lint index, fruit node numbers, growth period for three yield types. The high yield type ex- hibited the highest bolls per plant, lint percentage and lint index, the lowest fruit node numbers and the shortest growth period. Bolls per plant, boll weight and single plant lint yield were significantly and positively correlated. Fruit node numbers and single plant lint yield were significantly and negatively correlated. Bolls per plant, boll weight, and fruiting position number were the most important factors influencing single plant lint yield of upland cotton lines with high quality. [ Conclusion ] The results will have certain significance for the development of upland cotton variety with high quality. 展开更多
关键词 Upland cotton high quality Lint yield Agronomic trait
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Effects of Seed Soaking with Uniconazole and Substrate Formula on Seedling Quality of Rapeseed 被引量:3
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作者 高建芹 浦惠明 +4 位作者 龙卫华 胡茂龙 陈松 周晓婴 张维 《Agricultural Science & Technology》 CAS 2015年第9期1943-1949,共7页
[Objective] To cultivate blanket rapeseed seedlings suitable for automatic mechanical transplanting, the effects of seed soaking with uniconazole and substrate formula on seed germination and seedling quality of rapes... [Objective] To cultivate blanket rapeseed seedlings suitable for automatic mechanical transplanting, the effects of seed soaking with uniconazole and substrate formula on seed germination and seedling quality of rapeseed were investigated using HY4 as the material. [Method] The rapeseed seeds were soaked in different concentrations(0, 5, 10, 20, 30, 40 and 50 mg/L) of uniconazole for 0, 1, 2, 4 and8 h, respectively. Subsequently, they were dried naturally. After the preliminary screening carried out in petri dishes and in a laboratory, the optimum soaking concentration and time of uniconazole were obtained. On the other hand, the rapeseed seeds were soaked in different concentrations(0, 5, 10, 15 and 20 mg/L) of uniconazole for 0, 1 and 2 h, respectively for outdoor pot experiment. At the same time, the screening of optimum substrate formula for cultivating blanket rapeseed seedlings was carried out. The field test was carried out to verify the screened optimum substrate formula. [Result] The results of petri dish experiment showed that seed soaking with uniconazole could delay seed germination, reduce seed germination rate, inhibit hypocotyl elongation and promote root growth. When the soaking concentration exceeded 30 mg/L and soaking time exceeded 2 h, the effect of seed soaking with uniconazole on seed germination was greater, and the seed soaking inhibited root growth. The results of outdoor pot experiment showed that the soaking concentrations and times all significantly reduced seedling height, slowed shoot growth and promoted root growth, which all contributed to the cultivation of blanket rapeseed seedlings suitable for automatic mechanical transplanting. In the substrate formula, the lower the proportion of soil was, the better the seedling growth was. In the substrate with lower proportion of soil, the seed germination rate, plant height,root vigor and dry matter accumulation were all increased(P〈0.05), which was verified by the field test. When the soaking concentration was less than 10 mg/L and soaking time was less than 1 h, the uniconazole showed weaker regulation effect on seedling growth, and the rapeseed seedlings were higher. In the substrate with soil proportion less than 50%, the adequate fertility relatively weakened the regulation effect of uniconazole on seedling growth, and the rapeseed seedlings were larger. [Conclusion] When the soaking concentration ranged within 15-20 mg/L and soaking time ranged within 1-2 h and the proportion of soil in substrate was 50%,the height of cultivated rapeseed seedlings was less than 18 cm, there were 5-6leaves remained on each plant and the nursing period was shortened to 30-40 d,which were all beneficial to industrial production. 展开更多
关键词 UNICONAZOLE Seed soaking Substrate formula seedling quality
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Effects of High Temperature Stress on Growth of Stress-Tolerant Rice Seedlings with Resistibility 被引量:4
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作者 张晓晶 张思远 +1 位作者 李春青 张文会 《Agricultural Science & Technology》 CAS 2014年第4期576-578,584,共4页
Two heat-tolerant rice varieties, N5 and TQ, were chosen as test materi- als. Specifically, rice seedlings (leaf age at 2.1), cultivated in room, were treated at 40 ℃ for 7 d and some indices were measured, includi... Two heat-tolerant rice varieties, N5 and TQ, were chosen as test materi- als. Specifically, rice seedlings (leaf age at 2.1), cultivated in room, were treated at 40 ℃ for 7 d and some indices were measured, including plant height, dry weight, leaf color, proline, malondialdehyde and conductivity. The results showed that high temperature advanced the growth of N5 seedlings, for example, plant height, root length and dry weight of ground parts all increased. However, high temperature prevented TQ seedlings growth, plant height in particular. Furthermore, high temper- ature treatment increased the content of chlorophyll of N5 and had none effects on PSII of N5, with little damages on membrane system. On the other hand, high temperature actually reduced PSII activity of TQ, and seriously damaged TQ mem- brane system. It is speculated that the differences of the two varieties lie on pro- duction or removing capacity of reactive oxide species. 展开更多
关键词 high temperature stress Rice seedlings TOLERANCE
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Evaluation of Productivity and Light Quality in Two High Density Dwarf Rootstock Apple Orchards in Central China 被引量:2
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作者 高登涛 郭景南 +2 位作者 魏志峰 范庆锦 杨朝选 《Agricultural Science & Technology》 CAS 2012年第9期1848-1853,2011,共7页
[Ohjective] The aim of the study is to investigate the productivity and light quality in two high density M26 dwarf rootstock apple orchards in central China so as to provide some management guidance for close plantin... [Ohjective] The aim of the study is to investigate the productivity and light quality in two high density M26 dwarf rootstock apple orchards in central China so as to provide some management guidance for close planting of dwarf rootstock apples.[Method] The technical parameters of individual trees and group parameters as shoot number and composition and canopy coverage were determined, and the light quality in the canopy, fruit production and quality were investigated. [Result] Slender spindle (SS) orchard has 54 thousands shoots per 667 m^2. Coverage rate is 76%. Leaf area index is 1.9. The ratio of long, medium and spur shoots is 1:1:8. Fruit yield is 3 263 kg/667 m^2 with 85% first grade fruit. Light interception in the canopy is 58% while the ratio of canopy with good light is 65%. Modified slender spindle (MSS) orchard has 93 thousands shoots per 667 m^2 and the coverage is 77%. Leaf area index is 3.3. The ratio cf long, medium and spur shoots is 1:2:7. Fruit yield is 3 931 kg/667 m^2 with 85% first grade fruit. The light interception in the canopy is 73% while the ratio of canopy with good light is 35%. [Conclusion] Apple orchard with M26 dwarf rootstock trained as SS and MSS tree form in medium planting density may be useful to the management of the similar orchards in Central China. 展开更多
关键词 Apple trees on dwarf rootstocks high density planting Tree form Pro-ductivity Light quality
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Study on Seedling Quality of Double-cropping Late Rice Sowed at Different Dates in Guangdong 被引量:1
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作者 饶刚顺 肖立中 +4 位作者 田晋元 黄忠林 杜尧东 陈新光 唐湘如 《Agricultural Science & Technology》 CAS 2011年第7期975-979,共5页
[Objective] The aim was to study seedling quality of rice sowed at different dates so as to provide theoretical basis for determining the best seeding time.[Method] By investigating the characters of shoot and root of... [Objective] The aim was to study seedling quality of rice sowed at different dates so as to provide theoretical basis for determining the best seeding time.[Method] By investigating the characters of shoot and root of different varieties sowed at different dates,the best seeding time of double-cropping late rice was determined.[Result] The first leaf sheath height and the second leaf length shared significantly positive correlation,which fit the quadratic equation well.The effects of different sowing dates on shoot and root of three rice varieties appeared significant difference.[Conclusion] The best seeding time of Tianyou428 was in June 25-July 2 and that of Tianyou998 and Yuxiangyouzhan was in July 2-9. 展开更多
关键词 Seeding time Late rice seedling quality Fitting equation
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Effects of Different Upland Seedling Nurturing Modes on Shed Temperature and Rice Seedling Quality
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作者 韩康顺 贾玉敏 +3 位作者 时羽 孟令君 李彦利 邵玺文 《Agricultural Science & Technology》 CAS 2016年第1期63-68,共6页
In order to compare the advantages and disadvantages of large-shed,middle-shed and small-shed upland seedling nurturing modes in japonica rice planting regions of North China, in this study, Tongyin 58, Tonghe 836 and... In order to compare the advantages and disadvantages of large-shed,middle-shed and small-shed upland seedling nurturing modes in japonica rice planting regions of North China, in this study, Tongyin 58, Tonghe 836 and Tonghe 835 were used as experimental materials and cultivated with large-shed, middle-shed and small-shed upland seedling nurturing modes to investigate active and effective accumulated temperature and rice seedling quality. According to the results, active and effective accumulated temperature in three different upland seedling nurturing treatments during seedling nurturing period were generally in a descending order of large shed 〉 middle shed 〉 small shed. The occurrence frequency of temperature exceeding the biological upper limit for rice growth in different upland seedling nurturing treatments demonstrated a descending order of large shed 〉 small shed 〉middle shed; the occurrence frequency of temperature below the biological lower limit demonstrated a descending order of small shed 〉 middle shed 〉 large shed.Plant height, root number, aboveground dry weight, underground dry weight and emergence rate varied significantly among different upland seedling nurturing modes,which showed a descending order of large shed 〉 middle shed 〉 small shed; leaf age and stem number in large shed was significantly higher than that in middle and small sheds, but there was no significant difference in leaf age and stem number between middle and small sheds; underground dry weight varied slightly between large and middle shed, but underground dry weight in large and middle shed was remarkably higher than that in small shed. In production, large-shed upland seedling nurturing is most appropriate technique, followed by middle-shed upland seedling nurturing. In large-shed upland seedling nurturing, ventilation and seedling hardening should be strengthened. Small-shed upland seedling nurturing technique is not recommended to be used in regions with low accumulated temperature at night. In small-shed upland seedling nurturing, the minimum temperature at night should be concerned, and heat preservation measures should be taken immediately when there is a sudden drop in temperature. 展开更多
关键词 Upland seedling nurturing modes Shed temperature seedling quality
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The Application of Seedling Nursing on Moist Trays and Fermentation Heating Using Farmyard Manure Methods in High-altitude Tobacco Areas of Fenggang County
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作者 王玉科 彭晓忠 +4 位作者 周红江 张维军 罗玉英 王启均 王克敏 《Agricultural Science & Technology》 CAS 2015年第5期909-911,939,共4页
To solve the problems of long seedling culture time and poor quality of tobacco seedlings bred by floating culture technique of seedlings in high-altitude tobacco areas, a comparative trial between seedling nursing on... To solve the problems of long seedling culture time and poor quality of tobacco seedlings bred by floating culture technique of seedlings in high-altitude tobacco areas, a comparative trial between seedling nursing on moist trays + fermentation heating using farmyard manure and conventional floating culture of seedlings in Fenggang County was carried out in 2013. The results showed that seedling nursing on moist trays + fermentation heating using farmyard manure can improve 4-5 ℃ of pool water temperature, shorten 8 d of seedling age, increase 4.45 cm of seedling height, thicken 0.46 cm of stem girth and make lateral root system developed. The method can shorten the time of floating breeding of flue-cured tobacco,improve the quality of tobacco seedlings, thus it was suitable to popularize in highaltitude tobacco areas of Fenggang County. 展开更多
关键词 Flue-cured tobacco. seedling nursing seedling quality
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Effects of soilless substrates on seedling quality and the growth of transplanted super japonica rice 被引量:11
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作者 LEI Wu-sheng DING Yan-feng +2 位作者 LI Gang-hua TANG She WANG Shao-hua 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2017年第5期1053-1063,共11页
This study was conducted to investigate the effects of soilless substrates of hydroponically grown long-mat seedlings (HLMS) on seedling quality and field growth characteristics of transplanted super japonica rice. ... This study was conducted to investigate the effects of soilless substrates of hydroponically grown long-mat seedlings (HLMS) on seedling quality and field growth characteristics of transplanted super japonica rice. A widely grown conventional super japonica rice cultivar (Wuyunjing 23) was selected as the test material. The effect of HLMS on seedling quality, mechanical transplantation quality, field growth characteristics, yield, and benefit-cost ratio were compared with seedlings grown in organic substrates and traditional nutritive soil, whJch was selected as the control. Root number, root twJstJng power and root activity of seedlings cultivated by HLMS were decreased compared to that of the organic substrates andcontrol. However, seedling root length as well as aboveground growth were increased compared to the organic substrates and control seed- lings. In the HLMS, the content of gibberellin acid (GA3) decreased while abscisic acid (ABA) content increased compared to that of the organic substrates and control seedlings. During the early stages after transplanting, the re-greening of HLMS was delayed compared to that of the organic substrates and control seedlings. Nevertheless, there were no significant differences in tiller dynamics and crop yield among the HLMS, organic substrates and control treatments. The effects of HLMS on seedling production were similar to those of the organic substrates and traditional nutritive soil in the present study, suggesting that HLMS have the potential to replace traditional nutritive soil in seedling production without decreasing crop yield. Finally, it is important to reduce organic substrates and topsoil dependence during rice seedling production and worthwhile to consider HLMS popularization and its application on a larger scale. 展开更多
关键词 super hybrid rice (Oryza sativa L.) mechanical transplantation seedling quality YIELD seedling raised method
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Effect of electromagnetic stirring in mold on the macroscopic quality of high carbon steel billet 被引量:9
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作者 Haiqi YU Miaoyong ZHU 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2009年第6期461-467,共7页
An industrial plant trial for optimizing the process parameters in a round billet continuous casting mold with electromagnetic stirring (M-EMS) was performed, in which the influences of stirring parameters with M-EM... An industrial plant trial for optimizing the process parameters in a round billet continuous casting mold with electromagnetic stirring (M-EMS) was performed, in which the influences of stirring parameters with M-EMS on the solidification macrostructure of high carbon steel were investigated. The results show that the billet quality is not well controlled under the condition of working current and frequency with EMS, in which the subsurface crack of grade 1.0-2.0 ups to 38.09%, the central pipe of grade 1.0-1.5 reaches to 14.28%, and the central porosity of grade 1.5 is 14.29%. The parameters of current 260 A and frequency 8 Hz as the final optimum scheme has a remarkable effect for improving the macroscopic quality of billet, in which the subsurface crack, central pipe and skin blowhole are all disappeared, and the central porosity and carbon segregation are also well improved. 展开更多
关键词 Round billet continuous casting Electromagnetic stirring in mold Macroscopic quality high carbon steel
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Diagenetic Evolution and Formation Mechanisms of High-Quality Reservoirs under Multiple Diagenetic Environmental Constraints:An Example from the Paleogene Beach-Bar Sandstone Reservoirs in the Dongying Depression,Bohai Bay Basin 被引量:5
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作者 WANG Jian CAO Yingchang +1 位作者 SONG Guoqi LIU Huimin 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2017年第1期232-248,共17页
The diagenetic environment, diagenetic responses, diagenetic transformation model and formation mechanisms of high-quality reservoirs(beach-bar sandstones of the Paleogene fourth member) in the Dongying depression w... The diagenetic environment, diagenetic responses, diagenetic transformation model and formation mechanisms of high-quality reservoirs(beach-bar sandstones of the Paleogene fourth member) in the Dongying depression were studied through the analysis of fluid inclusions, thin section and burial evolution history. The diagenetic fluids of the beach-bar sandstone reservoirs evolved from early high salinity and weak alkalinity to low salinity and strong acidity, late high salinity and strong alkalinity and late low salinity and acidity, which were accompanied by two stages of oil and gas filling. The fluids at the margins of the sandbodies were continuously highly saline and strongly alkaline. The western(eastern) reservoirs experienced early open(closed), middle open, and late closed diagenetic environments during their burial history. The flow pattern was characterized by upwelling during the majority of the diagenesis(in the east, a non-circulating pattern transitioned into an upwelling current). Due to the evolution of the diagenetic fluids, the diagenetic sequence of the beach-bar reservoirs was as follows: early weak carbonate cementation; feldspar and carbonate cement dissolution and authigenic quartz cementation; late carbonate and anhydrite cementation, authigenic feldspar cementation, and late quartz dissolution; and late carbonate cementation, feldspar dissolution, and authigenic quartz cementation. The diagenetic strength during these stages varied or was absent altogether in different parts of the reservoirs. Due to the closeness of the diagenetic environment and the flow pattern of the diagenetic fluids, the diagenetic products are variably distributed in the sandstones interbedded with mudstones and in the fault blocks. The evolution of multiple alternating alkaline and acidic diagenetic environments controlled the distribution patterns of the reservoir diagenesis and reservoir space, and the reservoir quality index, RQI, increased gradually from the margins to the centers of the sandstones. The closeness of the diagenetic environment and the flow patterns of the diagenetic fluids controlled the differences in the reservoir properties among the fault blocks. With increasing distance from the oil-source faults, the RQI values in the west gradually decreased and in the east initially increased and then decreased. 展开更多
关键词 diagenetic environment DIAGENESIS diagenetic fluids beach-bar high quality reservoir Dongying depression
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Coinoculation of bioinoculants improve Acacia auriculiformis seedling growth and quality in a tropical Alfisol soil 被引量:4
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作者 Thangavelu Muthukumar Karuthamuthu Udaiyan 《Journal of Forestry Research》 SCIE CAS CSCD 2018年第3期660-670,共11页
We conducted a study to find out if arbuscular mycorrhizal(AM) fungi(Acaulospora scrobiculata,Scutellospora calospora) and phosphate solubilizing bacteria(PSB, Paenibacillus polymyxa) inoculation either individually o... We conducted a study to find out if arbuscular mycorrhizal(AM) fungi(Acaulospora scrobiculata,Scutellospora calospora) and phosphate solubilizing bacteria(PSB, Paenibacillus polymyxa) inoculation either individually or in combinations can improve Acacia auriculiformis seedling growth, uptake of nutrients and quality in a phosphorus deficient tropical Alfisol. The seedlings were assessed for various growth and nutrient uptake parameters after 60 days of treatment. Inoculation with P.polymyxa stimulated mycorrhizal formation. Seedling height, stem girth, taproot length, number of leaves and leaf area, plant dry matter production, nodulation, and nodular dry weight were significantly higher for seedlings that were either dual inoculated or triple inoculated compared to individual inoculation of AM fungi or PSB, and uninoculated seedlings. Dual and triple application of AM fungi and PSB also significantly improved the nutrient contents of shoots and roots and nutrient uptake efficiencies. The calculated seedling quality indexes of the AM fungi and PSB inoculated seedling were 25–208% higher than uninoculated seedlings. These findings show that A.auriculiformis seedlings when dual inoculated or triple inoculated performed better than seedlings inoculated with the microbes individually and compared with uninoculated control seedlings. We conclude that bioinoculation is important for the production of high-quality A.auriculiformis seedlings in tree nurseries for planting in nutrient deficient soils. 展开更多
关键词 Arbuscular mycorrhizal fungi Nutrient uptake efficiency Paenibacillus polymyxa Relative field mycorrhizal dependency seedling quality
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Effect of carbon and nitrogen ratio control on Artemia growth, water quality, biofloc microbial diversity under high salinity and zero-water exchange culture condition 被引量:3
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作者 WANG Shanyue CUI Xueping +2 位作者 XU Ruyi GAO Meirong SUI Liying 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2019年第5期1768-1776,共9页
Biofloc technology has been applied successfully in the intensive aquaculture of several fish and shrimp species. The growth of heterotrophic microorganisms can be stimulated through adding extra carbon, which reduces... Biofloc technology has been applied successfully in the intensive aquaculture of several fish and shrimp species. The growth of heterotrophic microorganisms can be stimulated through adding extra carbon, which reduces the nitrogen level in the water and provides microbial protein to the animals. However, most of the studies and practical applications have been conducted in freshwater and marine environment. This paper focused on brine shrimp Artemia that lives in high salinity environment together with other halophilic or halotolerant microorganisms. The effect of carbon supplementation on Artemia growth, water quality, and microbial diversity of biofl ocs was studied in the closed culture condition without any water exchange. The salinity of the culture medium was 100. A 24-d culture trial was conducted through supplementing sucrose at carbon/nitrogen (C/N) ratio of 5, 15, and 30 (Su5, Su15, and Su30), respectively. The culture without adding sucrose was used as a control. Artemia was fed formulated feed at a feeding ration of 60% recommended feeding level. The results showed that sucrose supplementation at higher C/N ratio (15 and 30) signifi cantly improved the Artemia survival, growth and water quality ( P <0.05). Addition of sucrose at C/N ratio of 15 and 30 significantly increased biofloc volume (BFV)( P <0.05). The Illumina MiSeq sequencing analysis showed that supplementing carbon at C/N ratio of 15 had a better total bacterial diversity and richness, and shaped the microbial composition at genera level. This study should provide information for studying the mechanism of biofloc technology and its application in high salinity culture conditions. 展开更多
关键词 biofl OCS C/N ratio ARTEMIA GROWTH water quality MICROBIAL diversity high throughput SEQUENCING
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Effect of seedling age and water depth on morphological and physiological aspects of transplanted rice under high temperature 被引量:4
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作者 KHAKWANI Abdul Aziz SHIRAISHI Masaaki +3 位作者 ZUBAIR Muhammad BALOCH Mohammad Safdar NAVEED Khalid AWAN Inayatullah 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2005年第5期389-395,共7页
To study the effect of high temperature, rice seedlings 20, 30, 40 and 50 d were kept at 5, 10, 15 and 20 cm water depth in a water pool. Meteorological findings indicated that water temperature varied up to 10 cm but... To study the effect of high temperature, rice seedlings 20, 30, 40 and 50 d were kept at 5, 10, 15 and 20 cm water depth in a water pool. Meteorological findings indicated that water temperature varied up to 10 cm but became stable below this depth. Deep water inflicted higher tiller mortality, minimal increase in dry weight of aerial parts and leaf area, decrease in root length, and decrease in root dry weight especially at 20 cm water depth and produced an unbalanced T/R ratio (top versus root dry weight). However, deep water tended to increase plant length. These parameters, however, excel in shallow water. Older seedlings, with the exception of root dry weight, could not perform well compared to young seedlings in all physiological and morphological aspects. The study revealed that seedlings, particularly young ones, stand well in shallow water and can cope with high temperature. 展开更多
关键词 RICE high temperature seedling age Water depth
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Studies on Tomato Seedling Quality Indices Under Simulated Shipping and Storage Conditions 被引量:3
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作者 NINGWei GEXiao-guang LITian-lai 《Agricultural Sciences in China》 CAS CSCD 2004年第12期948-952,共5页
Indices of the tomato seedling quality maintenance level after production before field planting were studied through simulated experiments, small—scale operation, indoor analyses and measurements, and field observa... Indices of the tomato seedling quality maintenance level after production before field planting were studied through simulated experiments, small—scale operation, indoor analyses and measurements, and field observation. The results showed that under simulated shipping and storage conditions, seedling quality change following different durations (days) of shipping and storage was correlated significantly or even very significantly with certain physiological and morphological indices. With various measured indices following different periods of shipping and storage treatment subjected to multinomial successive regressive correlation analysis, the principal factors influencing seedling quality maintenance level are identified to be chlorophyll content →dry short weight → leaf freshness index in order of their importance. Significance analysis with multinomial fitted equation indicated that correlations between any one of above three factors and the growth index after field planting reached very significant difference level. 展开更多
关键词 Tomato seedling Shipping and storage after production Physiological change quality maintenance
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The Effect of High Temperature after Anthesis on Rice Quality and Starch Granule Structure of Endosperm 被引量:6
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作者 Zhang Guilian Liao Bin +1 位作者 Li Bo Cai Zhihuan 《Meteorological and Environmental Research》 CAS 2016年第3期72-75,共4页
To ascertain the effect mechanism of high temperature after anthesis on rice quality, the experiment was conducted with two rice lines, the heat-tolerant line 996 and heat-sensitive line 4628, with high temperature an... To ascertain the effect mechanism of high temperature after anthesis on rice quality, the experiment was conducted with two rice lines, the heat-tolerant line 996 and heat-sensitive line 4628, with high temperature and optimal temperature in the growth chamber to investigate the effect of high temperature stress after anthesis on rice appearance quality, milling quality, cooking and eating quality and starch granule structure of endo- sperm. The result showed that milled rice rate, head rice rate, amylose content and gel consistency of both lines decreased under high temperature stress after anthesis, while the ratio of grain length to width, chalky rate, chalkiness, protein content increased. Under high temperature treatments, gelatinization temperature, final viscosity, set back and peak time increased, breakdown decreased, Mg content and K content increased, Mg/K ra- tio decreased. Under same treatment, the extent of rice quality of heat tolerant line 996 affected by high temperature was lower than that of heat sensitive line 4628. Under high temperature stress after anthesis, starch granule arranged untightly, most of starch granules existed in the form of a single starch endosperm, refractive index decreased, transparency reduced, and led to the formation of chalk. Under high temperature stress af- ter anthesis, the increase of protein content, the decrease of Mg/K, the changes of rice RVA profile characteristics and starch granule structure of endosperm could be the main reason for the decrease of rice cooking and eating quality and appearance quality. 展开更多
关键词 high temperature stress after anthesis Rice quality ENDOSPERM Starch granule structure China
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