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An overview of grid-forming technology and its application in new-type power system
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作者 Zehong Liu Yu Sun Chao Ma 《Global Energy Interconnection》 EI CSCD 2024年第5期541-552,共12页
To address the global climate crisis,achieving energy transitions is imperative.Establishing a new-type power system is a key measure to achieve CO_(2) emissions peaking and carbon neutrality.The core goal is to trans... To address the global climate crisis,achieving energy transitions is imperative.Establishing a new-type power system is a key measure to achieve CO_(2) emissions peaking and carbon neutrality.The core goal is to transform renewable energy resources into primary power sources.The large-scale integration of high proportions of renewable energy sources and power electronic devices will dramatically change the operational mechanisms and control strategies of power systems.Existing wind and solar converters mostly adopt the grid-following control mode,which leads to significant challenges in system security and stability as it is insufficient to support the frequency and voltage of the grid.On the other hand,grid-forming control technology(GFM)can provide voltage and frequency support for the system,and thus becomes an effective measure to improve the inertia and damping characteristics of power systems.This paper illustrates the principles,control strategies,equipment types,application scenarios,and project implementation of grid-forming technology.The simulation and analysis based on a renewable-dominated real new-type power system show that GFM can significantly enhance the frequency and voltage support capacity of the power system,improve renewable energy accommodation capacity and grid transmission capacity under weak grid conditions,and play an important role in enhancing the stability and power supply reliability of renewable-dominated new-type power systems. 展开更多
关键词 new-type power system Renewable energy resources Grid-Forming(GFM) Control strategy
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Development of a stable attenuated double-mutant of tobacco mosaic virus for cross-protection
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作者 Xiaojie Xu Shaoyan Jiang +7 位作者 Chunju Liu Xujie Sun Qing Zhu Xiuzhai Chen Pengchao Jiang Fenglong Wang Yanping Tian Xiangdong Li 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第7期2318-2331,共14页
Tobacco(Nicotiana tabacum)and tomato(Solanum lycopersicum)are two major economic crops in China.Tobacco mosaic virus(TMV;genus Tobamovirus)is the most prevalent virus infecting both crops.Currently,some widely cultiva... Tobacco(Nicotiana tabacum)and tomato(Solanum lycopersicum)are two major economic crops in China.Tobacco mosaic virus(TMV;genus Tobamovirus)is the most prevalent virus infecting both crops.Currently,some widely cultivated tobacco and tomato cultivars are susceptible to TMV and there is no effective strategy to control this virus.Cross-protection can be a safe and environmentally friendly strategy to prevent viral diseases.However,stable attenuated TMV mutants are scarce.In this study,we found that the substitutions in the replicase p126,arginine at position 196(R^(196))with aspartic acid(D),glutamic acid at position 614(E^(614))with glycine(G),serine at position 643(S^(643))with phenylalanine(F),or D at position 730(D^(730))with S,significantly reduced the virulence and replication of TMV.However,only the mutation of S^(643) to F reduced the RNA silencing suppression activity of TMV p126.A double-mutant TMV-E614G-S643F induced no visible symptom and was genetically stable through six successive passages in tobacco plants.Furthermore,our results showed that TMV-E614G-S643F double-mutant could provide effective protection against the wild-type TMV infection in tobacco and tomato plants.This study reports a promising mild mutant for cross-protection to control TMV in tobacco and tomato plants. 展开更多
关键词 CROSS-PROTECTION double-mutant p126 tobacco mosaic virus VIRULENCE
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Comparison of Combustion Characteristics of Tars Produced with Tobacco Stem Biomass Gasification
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作者 Bo Chen Mingjun Wang +4 位作者 Bo Liu Chunping Lu Guohai Jia Yong Chao Chao Zhong 《Journal of Renewable Materials》 EI CAS 2024年第1期119-129,共11页
In order to study the combustion characteristics of tar in biomass gasifier inner wall and gasification gas,“tobacco stem semi-tar inside furnace”,“tobacco stem tar inside furnace”and“tobacco stem tar out-of-furn... In order to study the combustion characteristics of tar in biomass gasifier inner wall and gasification gas,“tobacco stem semi-tar inside furnace”,“tobacco stem tar inside furnace”and“tobacco stem tar out-of-furnace”were subjected to thermogravimetric experiments,and the combustion characteristics and kinetic characteristics were analyzed.The result shows that“tobacco stem semi-tar inside furnace”has the highest value and“tobacco stem tar out-of-furnace”is has the lowest value on ignition characteristics,combustion characteristics and combustible stability;“tobacco stem semi-tar inside furnace”has the lowest value and“tobacco stem tar outside furnace”has the highest value on burnout characteristics;“tobacco stem tar outside furnace”has the highest value and“tobacco stem tar inside furnace”has the lowest value on integrated combustion characteristics. 展开更多
关键词 tobacco stem TAR GASIFIER combustion characteristics
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Plant Chemical Defenses against Insect Herbivores—Using theWild Tobacco as a Model
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作者 Guangwei Sun Xuanhao Zhang +4 位作者 Yi Liu Liguang Chai Daisong Liu Zhenguo Chen Shiyou Lü 《Phyton-International Journal of Experimental Botany》 SCIE 2024年第4期641-659,共19页
The Nicotiana genus, commonly known as tobacco, holds significant importance as a crucial economic crop. Confrontedwith an abundance of herbivorous insects that pose a substantial threat to yield, tobacco has develope... The Nicotiana genus, commonly known as tobacco, holds significant importance as a crucial economic crop. Confrontedwith an abundance of herbivorous insects that pose a substantial threat to yield, tobacco has developed adiverse and sophisticated array of mechanisms, establishing itself as a model of plant ecological defense. Thisreview provides a concise overview of the current understanding of tobacco’s defense strategies against herbivores.Direct defenses, exemplified by its well-known tactic of secreting the alkaloid nicotine, serve as a potent toxinagainst a broad spectrum of herbivorous pests. Moreover, in response to herbivore attacks, tobacco enhancesthe discharge of volatile compounds, harnessing an indirect strategy that attracts the predators of the herbivores.The delicate balance between defense and growth leads to the initiation of most defense strategies only after aherbivore attack. Among plant hormones, notably jasmonic acid (JA), play central roles in coordinating thesedefense processes. JA signaling interacts with other plant hormone signaling pathways to facilitate the extensivetranscriptional and metabolic adjustments in plants following herbivore assault. By shedding light on these ecologicaldefense strategies, this review emphasizes not only tobacco’s remarkable adaptability in its natural habitatbut also offers insights beneficial for enhancing the resilience of current crops. 展开更多
关键词 tobacco HERBIVORE chemical defense jasmonic acid REGULATION
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Variations of phyllosphere microorganisms in asymptomatic and tobacco brown spot leaves before and after spraying 12% difenoconazole + fluxapyroxad SC
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作者 LI Tong WANG Hancheng +6 位作者 YE Guo WANG Qing NGANGUEM NZALLE Yranney Brice WANG Feng CAI Liuti FENG Ruichao ZHANG Songbai 《农药学学报》 CAS CSCD 北大核心 2024年第5期932-948,共17页
12%difenoconazole+fluxapyroxad SC(commercial name:Jiangong)was first released by BASF in China in 2016.It has been registered to control many diseases,including pear scab,apple Alternaria leaf spot,tomato early blight... 12%difenoconazole+fluxapyroxad SC(commercial name:Jiangong)was first released by BASF in China in 2016.It has been registered to control many diseases,including pear scab,apple Alternaria leaf spot,tomato early blight,cucumber powdery mildew,etc.This study evaluated the bioactivity of Jiangong against Alternaria alternata and explored variations of phyllosphere microorganisms in both asymptomatic and tobacco brown spot leaves at different persistence periods(0,5,10,and 15 days post-fungicide application)using high-throughput sequencing technology.The results indicated that Jiangong effectively inhibited mycelial growth(average EC_(50) value of 0.51μg/mL),conidia germination(average EC_(50) value of 3.47μg/mL),and the carbon metabolism of A.alternata.Both asymptomatic and symptomatic leaves presented complex microbial communities.Higher fungal diversity was noted in asymptomatic leaves,while higher bacterial diversity was found in symptomatic leaves.After application,the diversity and abundance of microbial community structures in both types of leaves changed over time.Fungal microbiome communities showed greater sensitivity than bacterial groups,with the microbiome communities of asymptomatic leaves being more affected than those of symptomatic leaves.Fungal community diversity decreased for both symptomatic and asymptomatic leaves after 5 days of application,while the diversity of fungal community in symptomatic leaves showed an upward trend after 10 days of application.Meanwhile,bacterial community diversity increased in both symptomatic and asymptomatic leaves after 5 days of application but then declined in asymptomatic leaves after 15 days.The abundance of the dominant function group of phyllosphere bacteria(metabolism,genetic information processing,environmental information processing)was not affected by the application of Jiangong.However,the abundance of the dominant function group of phyllosphere fungi(animal pathogen-endophyte-wood saprotroph,endophyte-plant pathogen,plant pathogen-undefined saprotroph)was significantly affected by the application of Jiangong,and high variation was found in symptomatic leaves than that of asymptomatic leaves.The application of Jiangong-induced alterations in the community structure of the tobacco phyllosphere microbiome provides a basis for future tobacco brown spot control strategies based on phyllospheric microecology. 展开更多
关键词 tobacco brown spot DIFENOCONAZOLE fluxapyroxad microorganism communities diversity high-throughput sequencing
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Smokeless Tobacco Use among Women in Kasama District-Zambia
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作者 Gloria Kangwa Caroline Zulu +1 位作者 Kabwe Chitundu Jamia Milanzi 《Journal of Biosciences and Medicines》 2024年第6期129-148,共20页
Background: Smokeless tobacco is defined as a product that contains tobacco, is not smoked or burned at the time of use, and commonly consumed orally or nasally. These products can be placed in the mouth, cheek or the... Background: Smokeless tobacco is defined as a product that contains tobacco, is not smoked or burned at the time of use, and commonly consumed orally or nasally. These products can be placed in the mouth, cheek or the lip and are sucked or chewed. The Zambian government, in the 2019 country report, gave an estimated figure of 4.5% of females aged 15 years and above in 2017 used smokeless tobacco and by 31st December, 2018, there was an increase of smokeless tobacco users to 6.8% women of the same age group. This study aimed to explore the extent of smokeless tobacco use among women in Kasama district-Zambia. Methodology: An analytical cross-sectional quantitative study design was used to collect data using the modified structured interview schedule, adopted from Medicine for Global Health. Simple random sampling method using rotary technique was used to select 430 respondents after meeting the inclusion criteria. Informed consent to participate in the study was obtained. Data was analysed using version 26.0 of the Statistical Package for Social Sciences. Appropriate parametric or non-parametric statistical tests (Chi-squared or Fisher’s exact test) were adopted in testing for associations between variables. Univariable and multivariable binary logistic regression analysis were employed in identifying smokeless tobacco use among women using an investigator-led stepwise approach, guided by various fit statistics and the likelihood ratio test. All statistical analyses adopted a 5% significance level at 95% confidence interval. Results: The results showed that most of the respondents were aged between 18 and 25 years (45.6%), (53.7%) lived in urban settlements and the majority (80%) were unemployed. The majority of respondents (83.5%) had a friend/relative who used smokeless tobacco and over half (53.5%) thought smokeless tobacco was beneficial to them. The commonly mentioned benefits of smokeless tobacco included body warmth (13.6%) and vaginal tightening (7.9%). The results revealed that most of the respondents attained a secondary level of education (38.4%). According to the study, smokeless tobacco use among women of Kasama-Zambia was significantly associated with the following;age (p Conclusion: Based on these findings, the study recommends that efforts should be channeled towards the dissemination of information on the impacts of smokeless tobacco use in order to overcome cultural beliefs attached to smokeless tobacco use. 展开更多
关键词 Smokeless tobacco Use KNOWLEDGE Educational Level Cultural Belief
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Determinants of Tobacco Cultivation and the Associated Impacts of Adoption in Hurungwe District, Zimbabwe
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作者 Spencer Sibanda Satoshi Tsuyuki 《Agricultural Sciences》 2024年第4期505-531,共27页
Tobacco is an essential cash crop in Zimbabwe and a strategic livelihood option for hundreds of thousands of rural households. However, the crop is linked to negative environmental, economic, and social impacts. The e... Tobacco is an essential cash crop in Zimbabwe and a strategic livelihood option for hundreds of thousands of rural households. However, the crop is linked to negative environmental, economic, and social impacts. The existing studies on tobacco cultivation in Zimbabwe present contradictory findings on the determinants and impacts of adoption, leaving unanswered questions about the crop’s sustainability impact in the country. This article investigates the determinants of smallholder farmers’ decisions to grow tobacco and the associated impacts of adoption. Random and purposive sampling were used to select 273 household surveys, including tobacco and non-tobacco smallholder farmers, and 56 expert interviews to answer the research questions. We employed regression models alongside expert interviews and document analysis to identify the determinants influencing the decision-making process of smallholder farmers in Zimbabwe regarding tobacco cultivation. Additionally, our investigation aimed to elucidate the perceived impacts associated with the adoption of this agricultural practice. The regression analysis indicated that the farmer’s age, education level, farming experience, family size, household income, and perceived high farm profitability are significant drivers of tobacco adoption. We also discovered divergent and convergent perceptions of the critical impacts of tobacco cultivation. The study highlights the need for proactive multi-stakeholder collaboration and sustainable financial arrangements to address the negative impacts of tobacco production. As the primary stakeholder responsible for regulating and promoting agricultural activities, the Zimbabwean government should provide meaningful financial support, increase access to credit, and ensure better market facilities for alternative crops to reduce the over-dependence on tobacco. 展开更多
关键词 tobacco Cultivation Determinants of Adoption Sustainability Impacts Economic Livelihood Stakeholder Perceptions
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Field Prevention and Control of Tobacco Black Shank in Guizhou Province
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作者 Yingjie JIANG Yongmo LI +2 位作者 Jun ZHOU Laifu LUO Yinsheng WANG 《Plant Diseases and Pests》 2024年第5期11-14,23,共5页
[Objectives]The paper was to explore the prevention and therapeutic schedule of tobacco black shank.[Methods]Different concentrations of 25 g/L fludioxonil·37.5 g/L metalaxyl-M,10 billion/mL Bacillus amyloliquefa... [Objectives]The paper was to explore the prevention and therapeutic schedule of tobacco black shank.[Methods]Different concentrations of 25 g/L fludioxonil·37.5 g/L metalaxyl-M,10 billion/mL Bacillus amyloliquefaciens,110 g/L amino acids·24 g/L manganese zinc,120 g/L calcium·20 g/L magnesium,and 4%metalaxyl-M·64%mancozeb were employed to assess their efficacy in controlling tobacco black shank.The disease index was subsequently evaluated.[Results]25 g/L fludioxonil·37.5 g/L metalaxyl-M+10 billion/mL B.amyloliquefaciens+110 g/L amino acids·24 g/L manganese zinc(transplanting dosage)or 120 g/L calcium·20 g/L magnesium(sealing dosage)(transplanting dosage:750 mL/hm 2+1.2×104 mL/hm 2+1.5×103 mL/hm 2,sealing dosage:1.5×103 mL/hm 2+1.2×104 mL/hm 2+1.5×103 mL/hm 2)resulted in a notable impact on the prevention of tobacco black shank.The incidence in the treated area was 10.78%,a 35.72%reduction compared to the control.The estimated yield was 99700 yuan/hm 2,a 34.91%increase compared to the control.25 g/L fludioxonil·37.5 g/L metalaxyl-M+10 billion/mL B.amyloliquefaciens+120 g/L calcium·20 g/L magnesium+4%metalaxyl-M·64%mancozeb(control dosage:1.5×103 mL/hm 2+1.2×104 mL/hm 2+1.5×103 mL/hm 2+1.5×103 g/hm 2,1.5×103 mL/hm 2+1.2×104 mL/hm 2+1.5×103 mL/hm 2+1.5×103 g/hm 2,with an interval of 7 d between applications)demonstrated a significant efficacy in controlling tobacco black shank.At 7 d following the second application,the relative preventive efficacy was observed to be 88.99%.Additionally,the estimated yield was 109900 yuan/hm 2,representing an increase of 244.51%compared to the control.[Conclusions]During the transplanting and sealing stages,25 g/L fludioxonil·37.5 g/L metalaxyl-M+10 billion/mL B.amyloliquefaciens+110 g/L amino acids·24 g/L manganese zinc(transplanting dosage)or 120 g/L calcium·20 g/L magnesium(sealing dosage)may be employed to enhance the growth of tobacco plants and mitigate the occurrence of tobacco black shank.Additionally,25 g/L fludioxonil·37.5 g/L metalaxyl-M+10 billion/mL B.amyloliquefaciens+120 g/L calcium·20 g/L magnesium+4%metalaxyl-M·64%mancozeb can be utilized for the treatment of tobacco black shank during the initial incidence stage. 展开更多
关键词 tobacco black shank PREVENTION TREATMENT FIELD
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Association of cannabis use disorder with atrial fibrillation in young men without concomitant tobacco use:Insights from nationwide propensity matched analysis
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作者 Bhavin Patel Sumanth Khadke +7 位作者 Kshitij Mahajan Avleen Dhingra Rishika Trivedi Samrath Singh Brar Sakshi Dixit Vaibhav Periwal Shaylika Chauhan Rupak Desai 《World Journal of Experimental Medicine》 2024年第3期64-71,共8页
BACKGROUND Recent data are inconclusive regarding the risk of arrhythmias among young cannabis users.Furthermore,many young adults use both cannabis and tobacco,which could add a residual confounding effect on outcome... BACKGROUND Recent data are inconclusive regarding the risk of arrhythmias among young cannabis users.Furthermore,many young adults use both cannabis and tobacco,which could add a residual confounding effect on outcomes.So,we studied young men who have cannabis use disorder(CUD)excluding tobacco use disorder(TUD)to understand their independent association with atrial fibrillation(AF)and related outcomes.AIM To study the association of CUD with AF and related outcomes.METHODS We used weighted discharge records from National Inpatient Sample(2019)to assess the baseline characteristics and mortality rates for AF-related hospitalizations in young(18-44 years)men in 1:1 propensity-matched CUD+vs CUD-cohorts without TUD.RESULTS Propensity matched CUD+and CUD-cohorts consisted of 108495 young men in each arm.Our analysis showed an increased incidence of AF in black population with CUD.In addition,the CUD+cohort had lower rates of hyperlipidemia(6.4%vs 6.9%),hypertension(5.3%vs 6.3%),obesity(9.1%vs 10.9%),alcohol abuse(15.5%vs 16.9%),but had higher rates of anxiety(24.3%vs 18.4%)and chronic obstructive pulmonary disease(COPD)(9.8%vs 9.4%)compared to CUD-cohort.After adjustment with covariates including other substance abuse,a non-significant association was found between CUD+cohort and AF related hospitalizations(odd ratio:1.27,95%confidence interval:0.91-1.78,P=0.15).CONCLUSION Among hospitalized young men,the CUD+cohort had a higher prevalence of anxiety and COPD,and slightly higher proportion of black patients.Although there were higher odds of AF hospitalizations in CUD+cohort without TUD,the association was statistically non-significant.The subgroup analysis showed higher rates of AF in black patients.Large-scale prospective studies are required to evaluate long-term effects of CUD on AF risk and prognosis without TUD and concomitant substance abuse. 展开更多
关键词 CANNABIS Marijuana Atrial fibrillation tobacco use disorder Original research SMOKING
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Correlation Analysis between Well-cellar Early Transplanting of Robust Seedlings and Diseases in Shiyan Tobacco-growing Area
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作者 Dingjun WANG Aihua LI +4 位作者 Liguang CHAI Dan LIU Yixia LIU Minggang LI Jingyang PENG 《Plant Diseases and Pests》 2024年第4期21-24,36,共5页
[Objectives]The paper was to investigate the relationship between the well-cellar early transplanting of robust seedlings and the prevalence of diseases in the Shiyan tobacco-growing area.[Methods]The relationship bet... [Objectives]The paper was to investigate the relationship between the well-cellar early transplanting of robust seedlings and the prevalence of diseases in the Shiyan tobacco-growing area.[Methods]The relationship between disease occurrence and meteorological factors during the field growth period was examined by analyzing the prevalence of flue-cured tobacco virus diseases,brown spot,and total disease in the Shiyan tobacco-growing area before(2013-2017)and after(2018-2022)the well-cellar early transplanting of robust tobacco seedlings.[Results]The implementation of a well-cellar early transplanting technique of robust seedlings resulted in a reduction in the average incidence of tobacco virus disease,brown spot,and total disease by 0.83%,8.85%,and 7.91%,respectively,in comparison to the incidence observed prior to early transplanting.These findings suggest that early transplanting can significantly reduce the incidence of flue-cured tobacco diseases.Prior to the well-cellar early transplanting of robust tobacco seedlings,there was a significant(including highly significant)positive correlation between the incidence of brown spot and total disease and precipitation in August and September.The incidence of brown spot and total disease in tobacco plants was found to be significantly positively correlated with May precipitation and significantly negatively correlated with May sunshine hours following the well-cellar early transplanting of robust seedlings.The advancement of the transplanting period by 20 d resulted in a reduction in the growing period of tobacco plants in the field under autumn rains(late August to November)in western China.This effectively circumvented the suitable conditions for disease occurrence and can reduce the incidence of disease.[Conclusions]This study offers a framework for enhancing the quality and efficiency of flue-cured tobacco production in the northwest tobacco-growing area of Hubei. 展开更多
关键词 tobacco disease Well-cellar early transplanting of robust seedlings Meteorological factor Correlation analysis Shiyan tobacco-growing area
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Production of Partial New-typed Brassica Napus by Introgression of Genomic Components from B. rapa and B. carinata 被引量:1
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作者 栗茂腾 刘建民 +2 位作者 王艳婷 余龙江 孟金陵 《Journal of Genetics and Genomics》 SCIE CAS CSCD 北大核心 2007年第5期460-468,共9页
A breeding strategy for widening the germplasm of Brassica napus was proposed by introgression of the A^r subgenome of B. rapa (A^rA^r) and C^c of B. carinata (B^cB^cC^cC^c) into natural B. napus (AnAncncn). The... A breeding strategy for widening the germplasm of Brassica napus was proposed by introgression of the A^r subgenome of B. rapa (A^rA^r) and C^c of B. carinata (B^cB^cC^cC^c) into natural B. napus (AnAncncn). The progenies with 38 chromosomes that were derived from the self-pollinated seeds of pentaploid hybrids (A^rA^nB^cC^cC^n) were used for further research. Some of the partial new-typed B. napus showed normal meiotic behavior, high portion of germinated pollen and normal embryological development. This indicates that the selected new-typed B. napus had a balanced genetic base. Molecular analysis showed that about 50% of the genome in the new-typed B. napus was replaced by A^r and C^c subgenome from B. rapa and B. carinata. Considering the genetic diversity among different lines of new-typed B. napus, it was deduced that the introgression of the genomic components from B, rapa and B. carinata could widen the genetic diversity of rapeseed. 展开更多
关键词 new-typed B. napus pollen germination embryo sac development genome introgression genetic distance
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Spatiotemporal Characteristics of Rural Labor Migration in China: Evidence from the Migration Stability under New-type Urbanization 被引量:7
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作者 DENG Wei ZHANG Shaoyao +3 位作者 ZHOU Peng PENG Li LIU Ying WAN Jiangjun 《Chinese Geographical Science》 SCIE CSCD 2020年第5期749-764,共16页
Although the factors affecting rural-to-urban migration have been discussed and analyzed in detail, few studies have examined the spatiotemporal dynamic characteristics of rural migrants’ employment and working-citie... Although the factors affecting rural-to-urban migration have been discussed and analyzed in detail, few studies have examined the spatiotemporal dynamic characteristics of rural migrants’ employment and working-cities in the post-immigrate era, which is essential for the citizenization and social integration of new-type urbanization in China. This study uses survey data from rural migration laborers across the eastern, central, and western China to construct a comprehensive labor migration stability index, and compares the determinants of the migration stability of rural labor among cities and industries using Geodetector. The results are as follows: 1) Compared with the midwestern cities, eastern cities have attracted younger and more skilled rural labor, and industries with higher technical content have higher migration stability among rural laborers. 2) Rural laborers more often adapt to changes by changing employment instead of changing working-cities. 3) The individual experiences of rural laborers and urban characteristics have significant impacts on the stability of migration, and family and societal guanxi(Chinese interpersonal relationships) enhance migration stability. 4) A unified labor market and convenient transportation have somewhat slowed industrial transfers and labor backflow. This study enhances our understanding of the roles of industrial transfer and new-type urbanization in shaping the labor geography landscape and provides policy implications for the promotion of people-oriented urbanization. 展开更多
关键词 migration stability rural labor Geodetector spatiotemporal characteristics new-type urbanization
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Paleoenvironments Recorded in a New-Type Ferromanganese Crust fromthe East Philippine Sea 被引量:1
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作者 徐兆凯 李安春 +1 位作者 蒋富清 李铁刚 《Journal of China University of Geosciences》 SCIE CSCD 2006年第1期34-42,共9页
We attempt to recover the paleocnvironments recorded in the accretion of a typical newtype hydrogenetic ferromanganese crust from the deep water areas of the East Philippine Sea. From detailed geochemical and U-series... We attempt to recover the paleocnvironments recorded in the accretion of a typical newtype hydrogenetic ferromanganese crust from the deep water areas of the East Philippine Sea. From detailed geochemical and U-series chronological studies, analysis of major and minor elements performed by X-ray fluorescence spectrometry (XRF) and inductively coupled plasma-mass spectrometer (ICPMS), three major accretion periods and corresponding paleocnvironments can be ascertained. The first period is a faster accretion period in the terminal Late Miocene to the Early Pliocene with looser structure and higher volcanic detritus content, corresponding to the active Antarctic bottom waters and depressed temperature from the intermediate Middle Miocene to the Early Pliocene. The second period is a pulse of pelagic clay deposition at the Early to Middle Pliocene, reflecting the shrinkage of the Antarctic bottom waters and the global temperature elevation of this period. The third period is a slower accretion period from the Middle Pliocene, which indicates the more violent activity of Antarctic bottom waters once again and more depressed temperature than the first period, facilitating the accretion of a more compact and pure ferromanganese zone. The paleoceanographic histories of these studied areas had not been made clear in previous research. 展开更多
关键词 new-type ferromanganese crust PALEOENVIRONMENT GEOCHEMISTRY East Philippine Sea
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Cultivating New-type Farmers Based on the Theory of Human Resources Development 被引量:3
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作者 ZHANG Li 《Asian Agricultural Research》 2010年第7期14-18,共5页
Under the direction of theory of human resources development,this thesis analyzes the impact of rural human resources development oncultivating new-type farmers.Firstly,it increases the input of rural basic education;... Under the direction of theory of human resources development,this thesis analyzes the impact of rural human resources development oncultivating new-type farmers.Firstly,it increases the input of rural basic education;secondly,it reinforces the vocational education and technologytraining;thirdly,it promotes the rural medical and public health services;fourthly,it quickens the rural labor transfer.The status quo of China's ruralhuman resources has been analyzed as follows:in terms of the quantity of rural human resources,the status quo is large and quick-developed baseof rural human resources,high labor participatory rate,and constitution of low age;in terms of the quality of rural human resources,the status quois the ubiquitous low quality of rural human resources,low technological level of rural human resources,and overall low physical quality of farmers;in terms of the structure of rural human resources,the status quo is the irrational industrial structure distribution and imbalanced regional structuredistribution.The thesis also discusses the edification of theory of human resources development in cultivating new-type farmers.First,in terms ofthe control over quantity of rural human resources,it is to keep the stability of family planning policy,and expedite the transfer of rural surplus la-bor;second,in terms of promoting the quality of rural human resources,it is to bolster the development of reserve rural labor force resources,toconstruct the adult educational training system with Chinese characteristics,and to build rural primary health care system;third,in terms of adjus-ting the structure of rural human resources,it is to perfect rural human resources market,and adjust rural economical structure and talents struc-ture. 展开更多
关键词 Development of human resources new-type farmers Educational training Rural surplus labor force China
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BUILDING A MODERATELY PROSPEROUS SOCIETY IN ALL RESPECTS——New-Type Industrialization 被引量:3
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作者 Zhang Qizi 《China Economist》 2020年第1期48-71,共24页
After announcing the goal of building a moderately prosperous society in all respects by 2020, the Chinese leadership also called for a new path of industrialization, putting a premium on quality and new development c... After announcing the goal of building a moderately prosperous society in all respects by 2020, the Chinese leadership also called for a new path of industrialization, putting a premium on quality and new development concepts. Unlike traditional industrialization in the broad or narrow sense, new-type industrialization features synergy between primary, secondary, and tertiary industries, integration between traditional economy and the new economy, environmental protection, technology progress, and innovation. It represents an inclusive approach to industrial development. At the fundamental level, the success of China’s new-type industrialization can be attributed to China’s inclusive learning and innovations. 展开更多
关键词 building a moderately prosperous society new-type industrialization inclusive learning and innovation
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Resistance characteristics of the ball packed-bed regenerator of the new-type swirl flow hot blast stove 被引量:1
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作者 Hongzhi Guo, Xiaohu Cheng, and Shuchen ZhangDepartment of Thermal Engineering, University of Science and Technology Beijing, Beijing 100083, China 《Journal of University of Science and Technology Beijing》 CSCD 2003年第1期21-24,共4页
A renovation project of miniaturization and high efficiency is provided for the hot blast stove .The experimental data tested feasibility of the new-type swirl flow hot blast stove. The normal and hot state experiment... A renovation project of miniaturization and high efficiency is provided for the hot blast stove .The experimental data tested feasibility of the new-type swirl flow hot blast stove. The normal and hot state experiments have been done through changing the angle of gas entering into the regenerator. Factors influencing pressure drop have been studied and analyzed. The experimental results can be formulated in the form of the Ergun equation. The regression equation is obtained. And two modified coefficients are offered to the regenerator pressure drop of the new-type swirl flow hot blast stove. 展开更多
关键词 the new-type swirl flow hot blast stove REGENERATOR regression equation resistance drop
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Characteristic Town: The Effective Path of New-type Urbanization with Chinese Characteristics Based on the Investigation of Intemet Town Wuzheng, Aficion Chocolate Town Jiashan, Photovoltaic Town Xiuzhou in Zhejiang 被引量:1
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作者 WU Zhen-ping 《Journal of Literature and Art Studies》 2018年第3期412-416,共5页
The characteristic town is a dynamic and vivid case of experience of Zhejiang. With the internet town Wuzheng, Aficion chocolate town Jiashan, photovoltaic town Xiuzhou in Zhejiang as the research perspective, the con... The characteristic town is a dynamic and vivid case of experience of Zhejiang. With the internet town Wuzheng, Aficion chocolate town Jiashan, photovoltaic town Xiuzhou in Zhejiang as the research perspective, the concept of development that the production, life and ecology merge together and the development direction and value of New-type urbanization is consistent, and it is the effective path of New-type urbanization development. At the same time, these towns provide a model for the development of the country small town 展开更多
关键词 haracteristic town new-type urbanization the production life and ecology merge together
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Dynamic changes and driving factors of land use under new-type urbanization: A case of Guiyang 被引量:1
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作者 ZENG Fang WEI Yuan 《Ecological Economy》 2015年第3期236-242,共7页
With the continuous progress of new-type urbanization in Karst mountain area, how to correctly deal with the relationship between urban economy and land use are attracting much attention. Based on the land-use change ... With the continuous progress of new-type urbanization in Karst mountain area, how to correctly deal with the relationship between urban economy and land use are attracting much attention. Based on the land-use change data, this paper analyzes the characteristics of land use change and its driving factors in Guiyang with the method of land-use dynamic analysis, land utilization and factor correlation analysis. We get the following results:(1) the change of land use was obvious during 2004 and 2012. The area of arable land and other land were decreased, the rate of decrease are 3.89% and 8.24%. In the meantime, a series of construction land and forest area increased a lot, the rate of increase are 3.89% and 8.24%.(2) The integrated land use dynamic degree of two research stages(2004-2009 and 2009-2012) were decreased from 2.12% to 0.34%, this suggests dynamic changes of land tend to be stable.(3) Four kinds of Land use class have a great contribution to the index of land use degree respectively. The composite index of land use degree rose from 229.58 to 247.19 during 2004 and 2012; the land use is still in the development stage.(4) Economy, population, transportation and policy guidance are the main drivers of land use change. 展开更多
关键词 new-type URBANIZATION LAND USE driving FACTORS GUI
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Green manuring facilitates bacterial community dispersal across different compartments of subsequent tobacco 被引量:2
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作者 LIANG Hai FU Li-bo +3 位作者 CHEN Hua ZHOU Guo-peng GAO Song-juan CAO Wei-dong 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2023年第4期1199-1215,共17页
Green manure–crop rotation is a sustainable approach to protect crops against diseases and improve yield.However,the mechanism by which green manuring manipulates the crop-associated microbial community remains to be... Green manure–crop rotation is a sustainable approach to protect crops against diseases and improve yield.However,the mechanism by which green manuring manipulates the crop-associated microbial community remains to be elucidated.In this study,we explored the horizontal processes of bacterial communities in different compartments of the soil–root interface(bulk soil,rhizosphere soil,rhizoplane and endosphere)of tobacco by performing a field experiment including four rotation practices,namely,tobacco rotated with smooth vetch,ryegrass,radish,and winter fallow(without green manure).Results showed that the co-occurrence networks constructed by adjacent compartments of the soil–root interface with green manuring had more edges than without green manuring,indicating dramatic microbial interactions.Green manuring increased the dispersal-niche continuum index between bulk soil and other compartments,indicating that it facilitated the horizontal dispersal of microbes.For the different green manuring practices,the neutral community model explained 24.6–27.6%of detection frequency for bacteria,and at least one compartment under each practice had a normalized stochasticity ratio higher than the 50%boundary point,suggesting that the deterministic and stochastic processes jointly shaped the tobacco microbiome.In conclusion,green manuring generally facilitates bacterial community dispersal across different compartments and enhances potential interactions among adjacent compartments.This study provides empirical evidence for understanding the microbiome assembly under green manure–crop rotation. 展开更多
关键词 green manure tobacco rotation practice niche compartment community assembly
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Numerical calculation of flow and heat transfer process in the new-type external combustion swirl-flowing hot stove
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作者 ShuchenZhang HongzhiGuo +3 位作者 XiangjunLiu ZhangpingCai XianchengGao SidongXu 《Journal of University of Science and Technology Beijing》 CSCD 2003年第5期31-34,共4页
It is clarified that the important method to improve the blast temperature ofthe small and the middle blast furnaces whose production is about two-thirds of total sum of Chinafrom 1000℃ to 1250-1300℃ is to preheat b... It is clarified that the important method to improve the blast temperature ofthe small and the middle blast furnaces whose production is about two-thirds of total sum of Chinafrom 1000℃ to 1250-1300℃ is to preheat both their combustion-supporting air and coal gas. The airtemperature of blast furnaces can be reached to 1250-1300℃ by burning single blast furnace coal gasif high speed burner is applied to blast furnaces and new-type external combustion swirl-flowinghot stove is used to preheat their combustion-supporting air. The computational results of the flowand heat transfer processions in the hot stove prove that the surface of the bed of the thermalstorage balls there have not eccentric flow and the flow field and temperature field distribution iseven. The computational results of the blast temperature distribution are similar to thosedetermination experiment data. The numerical results also provide references for developing anddesigning the new-type external combustion swirl-flowing hot stoves. 展开更多
关键词 new-type external combustion swirl-flowing hot stove flow field temperaturefield numerical calculation
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