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Characteristics of Temperature Change in China over the Last 2000 years and Spatial Patterns of Dryness/Wetness during Cold and Warm Periods 被引量:10
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作者 Quansheng GE Haolong LIU +2 位作者 Xiang MA Jingyun ZHENG Zhixin HAO 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2017年第8期941-951,共11页
This paper presents new high-resolution proxies and paleoclimatic reconstructions for studying climate changes in China for the past 2000 years. Multi-proxy synthesized reconstructions show that temperature variation ... This paper presents new high-resolution proxies and paleoclimatic reconstructions for studying climate changes in China for the past 2000 years. Multi-proxy synthesized reconstructions show that temperature variation in China has exhibited significant 50–70-yr, 100–120-yr, and 200–250-yr cycles. Results also show that the amplitudes of decadal and centennial temperature variation were 1.3℃ and 0.7℃, respectively, with the latter significantly correlated with long-term changes in solar radiation, especially cold periods, which correspond approximately to sunspot minima. The most rapid warming in China occurred over AD 1870–2000, at a rate of 0.56°± 0.42℃(100 yr)^(-1); however, temperatures recorded in the 20 th century may not be unprecedented for the last 2000 years, as data show records for the periods AD 981–1100 and AD1201–70 are comparable to the present. The ensemble means of dryness/wetness spatial patterns in eastern China across all centennial warm periods illustrate a tripole pattern: dry south of 25°N, wet from 25°–30°N, and dry to the north of 30°N. However, for all centennial cold periods, this spatial pattern also exhibits a meridional distribution. The increase in precipitation over the monsoonal regions of China associated with the 20 th century warming can primarily be attributed to a mega El Nino–Southern Oscillation and the Atlantic Multidecadal Oscillation. In addition, a significant association between increasing numbers of locusts and dry/cold conditions is found in eastern China. Plague intensity also generally increases in concert with wetness in northern China, while more precipitation is likely to have a negative effect in southern China. 展开更多
关键词 temperature change dry-wet spatial pattern cold and warm periods last 2000 years China
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An Analysis of China's Overall Price Trend During the 12th Five-year Plan Period and Suggestions
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作者 王双正 《China Economist》 2010年第6期120-133,共14页
In this paper,the author first summarizes China’s price operation situation and characteristics since the 1990s,and thenanalyzes inflation shaping factors and types.Based on that,the author raises six inflation early... In this paper,the author first summarizes China’s price operation situation and characteristics since the 1990s,and thenanalyzes inflation shaping factors and types.Based on that,the author raises six inflation early-warning indexes andfully dissects influencing factors of the overall price trend and inflation risks during the 12th Five-year Plan period.Afterthat,the author explains some aspects of price fluctuation that warrants attention during the 12th Five-year Plan period.Finally,the author puts forward policies and suggestions for stabilizing the overall price during the transformation of theeconomic development mode based on our actual situation. 展开更多
关键词 12th Five-year PLAN period overall PRICE level INFLATION TRANSFORMING ECONOMIC development mode
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Changes of China's various mineral resource reserves during the“Tenth-Five Year Plan”period from 2006 to 2010 被引量:1
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作者 Hao Ziguo,Fei Hongcai Liu Lian 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2011年第6期1518-1518,共1页
关键词 period from 2006 to 2010 Changes of China’s various mineral resource reserves during the Tenth-Five year Plan
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Monitoring and Assessment of Water Quality of Centralized Drinking Water Sources in Kaixian County during the " Twelfth Five-year Plan " Period 被引量:3
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作者 Li Zhang'an 《Meteorological and Environmental Research》 CAS 2015年第10期23-25,29,共4页
Based on the monitoring data of water quality of more than 40 centralized drinking water sources in 40 towns (townships or streets) of Kaixian County in the first and second half of each year during the "Twelfth Fi... Based on the monitoring data of water quality of more than 40 centralized drinking water sources in 40 towns (townships or streets) of Kaixian County in the first and second half of each year during the "Twelfth Five-year Plan" period, the changing rules of the water quality were studied to provide scientific references for the improvement of drinking water safety of urban and rural residents and drinking water quality. The re- sults show that the water quality of centralized drinking water sources in Kaixian County improved year by year during the "Twelfth Five-year Plan" period, and most monitoring sites with water quality exceeding the standard are distributed in reservoirs. Total phosphorus, total nitrogen, chemical oxygen demand, and permanganate index exceeded the standard obviously. Main pollution sources are domestic pollution and non-point source pol- lution caused by excessive discharge of nitrogen, phosphorus and organic pollutants. To improve drinking water quality, it is suggested that some towns can get drinking water from other reservoirs, surface water or underground water with better quality instead of previous reservoirs with water quality exceeding the standard, and the control of non-point source pollution should be enhanced. 展开更多
关键词 "Twelfth Five-year Plan" period Centralized drinking water Water quality~ Monitoring Assessment Kaixian County
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A Review of Development of Environmental Protection Information during the 12^(th) Five-Year Plan Period and Its Outlook 被引量:1
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作者 Zhang Fujiang 《Meteorological and Environmental Research》 CAS 2017年第3期67-70,共4页
During the 12^(th)Five-Year Plan period,the environmental protection information work made remarkable achievements,and the construction of nationwide air quality monitoring network was completed; the trinitarian monit... During the 12^(th)Five-Year Plan period,the environmental protection information work made remarkable achievements,and the construction of nationwide air quality monitoring network was completed; the trinitarian monitoring system was established,and environmental emergency command ability enhanced significantly. However,the issues of " information island" and " application silo" are still outstanding,and the application and promotion of new technologies make slow progress; the capacity of information system to support environmental protection business is insufficient,and there is no capacity for decision analysis. In the 13^(th)Five-Year Plan period,it is needed to strengthen the application and promotion of new technologies such as cloud computing,big data,Internet of Things,and spatial information,mainly construct and improve " Cloud Computing Based Environmental Protection( CCBEP) ", " big data platform of ecological environment",and then realize the core objective of improving environmental quality. 展开更多
关键词 the 12th Five-year PLAN period ENVIRONMENTAL information Review OUTLOOK
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Small Town Construction in the 13th Five-Year Plan Period: A Case Study of Shangrao City
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作者 Kun YANG Xifeng SHENG 《Asian Agricultural Research》 2016年第10期101-104,共4页
The 12 th Five-Year Plan period was unusual five years in the development of China. Under the dual pressure of complex international environment and arduous domestic reform task,China made outstanding achievements in ... The 12 th Five-Year Plan period was unusual five years in the development of China. Under the dual pressure of complex international environment and arduous domestic reform task,China made outstanding achievements in economic development,which lays a solid foundation for building a moderately prosperous society in all respects in the 13 th Five-Year Plan period. The key and difficult points of building a moderately prosperous society in all respects lie in solving issues concerning agriculture,farmers,and rural areas. The 18 th National Congress of the CPC stated that integrated urban and rural development is the fundamental approach for solving issues concerning agriculture,farmers,and rural areas. As a transitional form from rural areas to urban areas,small town play an important role in integrated urban and rural development. In the 13 th Five-Year Plan period,China should take a new road of characteristic urbanization,energetically develop key towns,central towns,and characteristic towns,use points to drive areas,and promote coordinated progress of urbanization construction and new countryside construction. Focusing on the objective of building a moderately prosperous society in all respects and taking Shangrao City as an example,we analyzed construction of small town,in order to provide scientific theoretical reference for urbanization development,plan preparation,and policy formulation of Shangrao City. 展开更多
关键词 13th Five-year Plan period Small town construction Shangrao City
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Variation of sea ice extent in different regions of the Arctic Ocean 被引量:4
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作者 CHEN Ping ZHAO Jinping 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2017年第8期9-19,共11页
Sea ice in the Arctic has been reducing rapidly in the past half century due to global warming. This study analyzes the variations of sea ice extent in the entire Arctic Ocean and its sub regions. The results indicate... Sea ice in the Arctic has been reducing rapidly in the past half century due to global warming. This study analyzes the variations of sea ice extent in the entire Arctic Ocean and its sub regions. The results indicate that sea ice extent reduction during 1979-2013 is most significant in summer, following by that in autumn, winter and spring. In years with rich sea ice, sea ice extent anomaly with seasonal cycle removed changes with a period of 4-6 years. The year of 2003-2006 is the ice-rich period with diverse regional difference in this century. In years with poor sea ice, sea ice margin retreats further north in the Arctic. Sea ice in the Fram Strait changes in an opposite way to that in the entire Arctic. Sea ice coverage index in melting-freezing period is an critical indicator for sea ice changes, which shows an coincident change in the Arctic and sub regions. Since 2002, Region C2 in north of the Pacific sector contributes most to sea ice changes in the central Aarctic, followed by C1 and C3. Sea ice changes in different regions show three relationships. The correlation coefficient between sea ice coverage index of the Chukchi Sea and that of the East Siberian Sea is high, suggesting good consistency of ice variation. In the Atlantic sector, sea ice changes are coincided with each other between the Kara Sea and the Barents Sea as a result of warm inflow into the Kara Sea from the Barents Sea. Sea ice changes in the central Arctic are affected by surrounding seas. 展开更多
关键词 Key words: Arctic sea ice extent period of 4-6 years sea ice margin sea ice coverage indices
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A Study on the Law of Birth and Formation of Yang-Deficiency Constitution Based on the Theory of Five Movement and Six Qi
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作者 Jingyi Bai Xinli Wen 《Journal of Clinical and Nursing Research》 2021年第5期54-57,共4页
Objective:To explore the law of birth and yang deficiency constitution based on the theory of five movements and six qi,as well as to provide a new way to better realize the prevention of yang deficiency constitution.... Objective:To explore the law of birth and yang deficiency constitution based on the theory of five movements and six qi,as well as to provide a new way to better realize the prevention of yang deficiency constitution.Methods:The data of TCM quality table and luck data were collected via questionnaires.According to the data of from the TCM quality table,the respondents were divided into yang deficiency constitution group and non-yang deficiency group.According to the luck data,the distributions of gestational age were compared between the two groups.Results:A total of 175 questionnaires were collected,of which 89 were non-yang deficiency constitution and 86 were yang deficiency constitution.The proportion of Ding year(15.1%)in the yang deficiency group was significantly higher than that in non-yang deficiency group(5.6%),in which the difference was statistically significant(P<0.05).Conclusion:The possibility of yang deficiency constitution is higher. 展开更多
关键词 Five movement six qi Yang deficiency constitution Gestational period year transport Prevention before illness
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Maximum Entropy Estimation of n-Year Extreme Waveheights 被引量:12
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作者 徐德伦 张军 郑桂珍 《海洋工程:英文版》 EI 2004年第2期307-314,共8页
A new method for estimating the n (50 or 100) -year return-period waveheight, namely, the extreme waveheight expected to occur in n years, is presented on the basis of the maximum entropy principle. The main p... A new method for estimating the n (50 or 100) -year return-period waveheight, namely, the extreme waveheight expected to occur in n years, is presented on the basis of the maximum entropy principle. The main points of the method are as follows: (1) based on the Hamiltonian principle, a maximum entropy probability density function for the extreme waveheight H, f(H)=αHγ e -βH4 is derived from a Lagrangian function subject to some necessary and rational constraints; (2) the parameters α, β, and γ in the function are expressed in terms of the mean , variance V= (H-)2 and bias B= (H-)3 ; and (3) with , V and B estimated from observed data, the n -year return-period wave height H n is computed in accordance with the formula 11-F(H n)=n , where F(H n) is defined as F(H n)=∫ H n 0f(H) d H. Examples of estimating the 50 and 100-year return period waveheights by the present method and by some currently used method from observed data acquired from two hydrographic stations are given. A comparison of the estimated results shows that the present method is superior to the others. 展开更多
关键词 maximum entropy n-year return-period waveheights Lagrangian function
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The Consumer Price Index of Residents in Cities and Countryside in July 1997(Same period of last year=100)
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《World Economy & China》 SCIE 1997年第5期49-49,共1页
关键词 same period of last year
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Foreign Capital Utilization During 10th Five Year Plan Period
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《China's Foreign Trade》 2000年第12期7-8,共2页
关键词 US WTO Foreign Capital Utilization During 10th Five year Plan period
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Problems and Opportunities for Biometeorological Assessment of Conditions in Cold Season
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作者 Elena S.Andreeva Sergey S.Andreev 《Journal of Atmospheric Science Research》 2023年第4期77-85,共9页
The article is devoted to a discussion of the possibilities of biometeorological assessment of the severity of weather conditions during the cold season.The relevance of the study is ensured not only by the fact that ... The article is devoted to a discussion of the possibilities of biometeorological assessment of the severity of weather conditions during the cold season.The relevance of the study is ensured not only by the fact that residents of a number of states,whose total number is more than 27 million people,live in these extreme climatic conditions,but also by the need to improve biometeorological approaches to assessing the impact of these conditions on the body and health of the population.This study examined biometeorological characteristics that illustrate a measure of cold stress.These include the Siple wind-chill index;Bodman winter severity index;Arnoldi weather hardness coefficient;Mountain wind chill index;weather hardness coefficient according to I.M.Osokin.The results of a comparison of winter severity assessments based on the values of the calculated Siple and Bodman indices made it possible to establish that the Bodman index is more acceptable when assessing mildly severe winters.The most adequate for assessing the“severity”of the cold period against the background of a decrease in air temperature and an increase in wind speed is the Siple index.The need to provide the countries of the world with high-quality hydrometeorological and biometeorological forecast information is justified and relevant.In this regard,these studies are very promising. 展开更多
关键词 Biometeorological indices Severe weather Cold period of the year “rigidity”of weather conditions Cold stress Biometeorological assessment
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海南热研73397等5个橡胶树品种全年割胶周期生胶质量变化
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作者 覃怀德 张安洋 +5 位作者 聂智毅 康桂娟 位明明 曾日中 罗微 湛瑞芳 《热带作物学报》 CSCD 北大核心 2024年第6期1226-1234,共9页
天然橡胶的质量和性能与橡胶树品种、割胶生产、气象、物候等遗传和环境因素密切相关。为了探明橡胶树不同品种之间及4—12月全年割胶周期内生胶质量的差异与变化规律,本研究分析比较了PR107、RRIM600、热研917、热研73397和热研879等5... 天然橡胶的质量和性能与橡胶树品种、割胶生产、气象、物候等遗传和环境因素密切相关。为了探明橡胶树不同品种之间及4—12月全年割胶周期内生胶质量的差异与变化规律,本研究分析比较了PR107、RRIM600、热研917、热研73397和热研879等5个橡胶树品种胶乳所制备生胶的质量,并分析了各品种5月份胶乳所制备生胶的硫化特性和硫化胶的力学性能。结果表明:5个橡胶树品种生胶的门尼黏度值、氮(蛋白质)含量、挥发物含量、P0和PRI值等在4—12月全年割胶周期内表现出增加或下降的趋势,这些质量指标既反映出橡胶树品种间的基因型差异,又表现出受气象等环境因素变化的影响。其中,4个品种12月生胶的蛋白质含量均超过3.0%;热研917混炼胶的硫化特性与其他4个品种有明显差异;在S/2 d/3割制下,热研879硫化胶的拉断伸长率和拉伸强度最小。本研究结果一方面有助于指导橡胶树品种选育和割胶生产,另一方面也可以为高性能天然橡胶生产加工提供科技支撑。 展开更多
关键词 橡胶树 橡胶质量与性能 全年割胶周期 海南岛
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“十四五”时期义乌市跨境电商发展的驱动机制研究 被引量:1
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作者 许珂 《中国商论》 2024年第9期45-48,共4页
义乌是中国小商品进入全球商贸流通体系的第一枢纽,也是引领全国跨境电商新模式、新业态发展的前沿阵地。加快发展跨境电商是新时期义乌打造全球大众贸易双循环中心,高质量、高水平建成世界小商品之都,实现经济社会数字化转型的关键路... 义乌是中国小商品进入全球商贸流通体系的第一枢纽,也是引领全国跨境电商新模式、新业态发展的前沿阵地。加快发展跨境电商是新时期义乌打造全球大众贸易双循环中心,高质量、高水平建成世界小商品之都,实现经济社会数字化转型的关键路径。本文通过回顾“十三五”时期义乌市跨境电商的发展历程,分析“十四五”时期义乌市跨境电商的发展趋势,评估当前义乌市跨境电商面临的问题和挑战,从而明确“十四五”时期义乌市跨境电商的总体要求和发展目标,制定“十四五”时期义乌市跨境电商的发展策略,以期为政府部门制定相关政策提供理论支撑与对策参考。 展开更多
关键词 “十四五”时期 跨境电商 电子商务 全球商贸流通
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1990-2019年中国慢性阻塞性肺疾病的疾病负担分析及未来10年发病预测
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作者 王文星 王璐 +3 位作者 邬超 戴江红 蒋红 高发水 《新疆医科大学学报》 CAS 2024年第1期135-140,共6页
目的了解1990-2019年中国慢性阻塞性肺疾病发病、患病、死亡情况及疾病负担情况,预测2020-2030年中国慢性阻塞性肺疾病发病情况,为评估和制定慢性阻塞性肺疾病相关预防治疗政策和措施提供数据支持。方法利用2019年全球疾病负担研究数据... 目的了解1990-2019年中国慢性阻塞性肺疾病发病、患病、死亡情况及疾病负担情况,预测2020-2030年中国慢性阻塞性肺疾病发病情况,为评估和制定慢性阻塞性肺疾病相关预防治疗政策和措施提供数据支持。方法利用2019年全球疾病负担研究数据库(Global burden of disease study,GBD),研究分析1990-2019年中国慢性阻塞性肺疾病的发病、患病、死亡、伤残调整寿命年(DALY)、早死寿命损失年(YLL)、伤残寿命损失年(YLD)等情况。采用贝叶斯-时期-队列分析(BAPC)方法,预测2020-2030年中国慢性阻塞性肺疾病发病率。结果相对于1990年,2019年中国慢性阻塞性肺疾病粗患病率增长35.44%,标化患病率减少27.16%,粗发病率增长38.31%,标化发病率减少28.52%,粗死亡率减少30.59%,标化死亡率减少70.08%。1990-2019年中国人群因慢性阻塞性肺疾病导致的YLL率由3281.48/10万降至862.37/10万,YLD率由330.33/10万降至240.40/10万,DALY率由3611.81/10万降至1102.77/10万。2019年男性慢性阻塞性肺疾病DALY率相比于1990年降低66.56%,女性DALY率相比于1990年降低71.87%。2020-2030年中国慢性阻塞性肺疾病标化发病率预计呈下降趋势,2030年男性标化发病率预计比2020年降低31.97%,女性标化发病率预计比2020年降低27.69%。结论1990-2019年,慢性阻塞性肺疾病对中国人口造成的疾病负担总体呈下降趋势。但从患病情况和死亡情况来看,发病及死亡人数较多,中国慢性阻塞性肺疾病的疾病负担仍处于较高水平。同时预测结果显示,未来10年中国慢性阻塞性肺疾病标化发病率在下降,但是仍处于较高水平,因此进行早筛查、早预防和早治疗,及广泛开展慢阻肺相关知识普及,对于做好COPD疾病管理具有重要意义。 展开更多
关键词 慢性阻塞性肺疾病 疾病负担 发病预测 伤残调整寿命年 贝叶斯-时期-队列分析
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Spatial Patterns of Precipitation Anomalies for 30-yr Warm Periods in China During the Past 2000 Years 被引量:3
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作者 郝志新 郑景云 +1 位作者 葛全胜 张学珍 《Acta meteorologica Sinica》 SCIE 2012年第3期278-288,共11页
The spatial patterns of precipitation anomalies during five 30-yr warm periods of 691-720, 1231-1260, 1741-1770, 1921-1950, and 1981-2000 were investigated using a dryness/wetness grading dataset covering 48 stations ... The spatial patterns of precipitation anomalies during five 30-yr warm periods of 691-720, 1231-1260, 1741-1770, 1921-1950, and 1981-2000 were investigated using a dryness/wetness grading dataset covering 48 stations from Chinese historical documents and 22 precipitation proxy series from natural archives. It was found that the North China Plain (approximately 35^-40~N, east of 105~E) was dry in four warm periods within the centennial warm epochs of 600-750, the Medieval Warm Period (about 900-1300) and after 1900. A wet condition prevailed over most of China during 1741-1770, a 30-yr warm peak that occurred during the Little Ice Age (about 1650-1850). The spatial pattern of the precipitation anomaly in 1981-2000 over East China (25^-40~N, east of 105~E) is roughly consistent with that in 1231 1260, but a difference in the precipitation anomaly appeared over the Tibetan Plateau. The spatial patterns of the precipitation anomalies over China varied between all five 30-yr warm periods, which implies that the matching pattern between temperature and precipitation change is multiform, and the precipitation anomaly could be positive or negative when a decadal warm climate occurs in different climate epochs. This result may provide a primary reference for the mechanism detection and climate simulation of the precipitation anomaly of the future warm climate. 展开更多
关键词 spatial patterns precipitation anomalies 30-yr warm periods past 2000 years China
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“十七年”时期中央文学研究所对文学新人的培养
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作者 施学云 《渤海大学学报(哲学社会科学版)》 2024年第2期75-82,共8页
“十七年”时期,中央文学研究所开启社会主义文学新人培养工程,培养新中国文学的新生力量。办学模式方面,侧重“小而精”的培训,招生计划、教学安排、师资队伍配备等体现了培养工农文学新人的诸多努力与创新。办学理念方面,既自由活泼,... “十七年”时期,中央文学研究所开启社会主义文学新人培养工程,培养新中国文学的新生力量。办学模式方面,侧重“小而精”的培训,招生计划、教学安排、师资队伍配备等体现了培养工农文学新人的诸多努力与创新。办学理念方面,既自由活泼,鼓励讨论争鸣;又严肃紧张,突出政治规训。办学质量评价方面,尽管人们常常诟病中央文学研究所培养的大作家和创作的名作品少,但综合考量其办学目标定位、生源质量与培养成效,大体实现了办学初衷,且对20世纪50—70年代乃至新时期初始作家队伍建设和文学生态建构都发挥了重要作用。 展开更多
关键词 “十七年” 中央文学研究所 文学新人 培养
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松材线虫潜育期延长导致红松越年枯死
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作者 王佳楠 姜生伟 +7 位作者 张瑞芝 李德斌 吴昊 徐昭 张亿珍 王家庆 李丹蕾 王峰 《林业科学》 EI CAS CSCD 北大核心 2024年第10期67-75,共9页
【目的】探究红松越年枯死的病理学过程和产生原因,以期为有效除治无松材线虫病症状的携带者松树提供理论依据。【方法】统计抚顺市大伙房实验林场自然侵染红松越年枯死比例,观测自然侵染和人工接种红松病症病状,测定红松当年显症的松... 【目的】探究红松越年枯死的病理学过程和产生原因,以期为有效除治无松材线虫病症状的携带者松树提供理论依据。【方法】统计抚顺市大伙房实验林场自然侵染红松越年枯死比例,观测自然侵染和人工接种红松病症病状,测定红松当年显症的松材线虫数量阈值。实验室内不同温度下测定松材线虫虫口增长情况,以及媒介昆虫羽化后适宜松材线虫虫口有效增长的时期(虫口增长期),计算从寄生关系的建立到症状开始出现的时间(潜育期),并揭示红松感染松材线虫后越年枯死的原因。【结果】截至6月,自然侵染红松的越年枯死比例为41.4%。观测的自然侵染和低剂量人工接种红松在被侵染或接种当年均未出现显著外部、内部症状变化,而是到翌年松脂分泌停止,树干水分低,针叶变红褐色,只有进行高剂量饱和接种才出现当年半数显症。病症表现为松材线虫能够正常侵染红松,可有效繁殖但在低温时繁殖受阻,可成功越冬但越冬后虫口数量骤减。红松显症的全株阈值St1=(163±22)条·g^(-1),局部阈值St2=(621±20)条·g^(-1)。以每株50000条的接种量接种38年生红松,在当年虫口增长期内全株松材线虫数量仅为(90±8)条·g^(-1),低于St1、局部松材线虫数量最高为(350±18)条·g^(-1),也低于St2。抚顺的虫口增长期(141天)比大连(154天)和南京(173天)短。经计算,抚顺市松材线虫的潜育期为146天,长于虫口增长期。【结论】云杉花墨天牛携带的松材线虫数量相对较低,导致初始侵染量低。松材线虫生命周期受温度特性的影响,表现为非增长期长、虫口增长期短,最终导致在虫口增长期内未能达到红松显症的松材线虫数量阈值。这些综合作用导致松材线虫潜育期延长,其中41.4%的死亡红松表现出越年枯死现象。 展开更多
关键词 松材线虫 越年枯死 初始侵染量 低温 虫口增长期 虫口增长
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有效推动新时代食用菌产业的高质量发展
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作者 刘寅山 孙达锋 +2 位作者 华蓉 赵春艳 董娇 《中国食用菌》 2024年第3期121-125,共5页
2022年12月8日,《易门县“十四五”食用菌产业发展规划(2021-2025年)》正式发布。本文中对《规划》颁布的背景和原因进行了简述,并从产业发展环境、总体思路、发展目标、产业空间及结构布局、重点任务、保障措施等方面对其内容进行解读... 2022年12月8日,《易门县“十四五”食用菌产业发展规划(2021-2025年)》正式发布。本文中对《规划》颁布的背景和原因进行了简述,并从产业发展环境、总体思路、发展目标、产业空间及结构布局、重点任务、保障措施等方面对其内容进行解读与特点分析,以期为推动新时代食用菌产业高质量发展提供参考。 展开更多
关键词 “十四五”规划 易门县 食用菌产业 产业空间及结构布局 政策保障
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大沽河极端气候指数特征及其对地下水的影响
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作者 李苏娜 周鹏鹏 +3 位作者 王广才 于晓曦 周光扬 冯衍扉 《中国农村水利水电》 北大核心 2024年第3期50-61,共12页
掌握极端气候变化特征是地下水资源管理的重要环节。为了探究极端气候对地下水资源的影响,以大沽河水源地为例,基于40余年的气象数据,选取14个代表性的极端气候指标,并采用线性趋势法、Mann-Kendall突变检验、小波分析等方法分析了研究... 掌握极端气候变化特征是地下水资源管理的重要环节。为了探究极端气候对地下水资源的影响,以大沽河水源地为例,基于40余年的气象数据,选取14个代表性的极端气候指标,并采用线性趋势法、Mann-Kendall突变检验、小波分析等方法分析了研究区气候变化的趋势性、突变性和周期性;基于极端气候指数和水文频率分析筛选了研究区代表性的极端气候年份,运用水均衡分析方法估算了极端气候年份条件下地下水平衡;并通过相关性和周期性分析评估了极端气候指数对地下水水位埋深的影响。结果表明:(1)1979-2021年,研究区内表征高温与降水的极端气候指数呈上升趋势,表征低温的极端气候指数总体呈下降趋势;极端丰水年代表性年份为2007年和2020年,极端枯水年代表性年份为1981年和1986年。(2)极端气候指数在20世纪90年代与21世纪初期发生突变,之后高温趋势更加显著。(3)极端降水指数第一周期对应的平均周期为11~16 a,极端气温指数第一主周期对应的平均周期主要有3个变化范围分别为20~24 a、12~14 a、5~6 a。(4)极端降水指数抑制地下水水位埋深的增加,极端降水量(R95p)和普通日降水强度(SDII)是影响大沽河水源地地下水水位埋深的主要降水指数;水位埋深的第一主周期对应的周期分别为13~15 a,与极端降水指数周期特征基本一致,意味着水位埋深受极端降水指数的影响较显著。(5)在极端丰水年(2007年),地下水总补给量约为319.4mm,总排泄量约为204.8 mm,均衡差约为114.6 mm;在极端枯水年(1981年),地下水总补给量约为104.2 mm,总排泄量约为141.1 mm,均衡差约为-36.9 mm。 展开更多
关键词 极端气候指数 极端气候年份 趋势性 突变性 周期性 地下水资源
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