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内蒙古苏尼特左旗南两类花岗岩同位素年代学及其构造意义 被引量:241
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作者 陈斌 赵国春 SimonWILDE 《地质论评》 CAS CSCD 北大核心 2001年第4期361-367,共7页
内蒙古北部索伦缝合带(索伦-苏尼特左旗-锡林浩特)被多数中外学者认为是西伯利亚板块南缘和华北板块北缘的最终缝合带。本文选择该缝合带上苏尼特左旗南两类花岗岩——与俯冲有关和与碰撞有关的岩浆岩(分别叫弧岩浆岩和碰撞花岗岩)进行... 内蒙古北部索伦缝合带(索伦-苏尼特左旗-锡林浩特)被多数中外学者认为是西伯利亚板块南缘和华北板块北缘的最终缝合带。本文选择该缝合带上苏尼特左旗南两类花岗岩——与俯冲有关和与碰撞有关的岩浆岩(分别叫弧岩浆岩和碰撞花岗岩)进行同位素年代学研究。结果表明:①弧岩浆活动有两期,分别约为490Ma和310Ma(锆石U-Pb,SHRIMP);碰撞花岗岩的侵位年代在230~250Ma(Rb-Sr全岩和锆石U-Pb);②根据本文新的年代学数据,索伦缝合带的最终缝合时间可能是在230~310Ma,这显然不同于国内多数学者坚持的“晚泥盆世碰撞”模式;而Sengor等推测的“晚二叠世碰撞”模式与本文数据一致。 展开更多
关键词 碰撞缝合 弧岩浆岩 碰撞花岗岩 同位素年龄 内蒙古 同位素年代学
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Plant abiotic stress response and nutrient use efficiency 被引量:118
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作者 Zhizhong Gong Liming Xiong +14 位作者 Huazhong Shi Shuhua Yang Luis R.Herrera-Estrella Guohua Xu Dai-Yin Chao Jingrui Li Peng-Yun Wang Feng Qin Jigang Li Yanglin Ding Yiting Shi Yu Wang Yongqing Yang Yan Guo Jian-Kang Zhu 《Science China(Life Sciences)》 SCIE CAS CSCD 2020年第5期635-674,共40页
Abiotic stresses and soil nutrient limitations are major environmental conditions that reduce plant growth,productivity and quality.Plants have evolved mechanisms to perceive these environmental challenges,transmit th... Abiotic stresses and soil nutrient limitations are major environmental conditions that reduce plant growth,productivity and quality.Plants have evolved mechanisms to perceive these environmental challenges,transmit the stress signals within cells as well as between cells and tissues,and make appropriate adjustments in their growth and development in order to survive and reproduce.In recent years,significant progress has been made on many fronts of the stress signaling research,particularly in understanding the downstream signaling events that culminate at the activation of stress-and nutrient limitation-responsive genes,cellular ion homeostasis,and growth adjustment.However,the revelation of the early events of stress signaling,particularly the identification of primary stress sensors,still lags behind.In this review,we summarize recent work on the genetic and molecular mechanisms of plant abiotic stress and nutrient limitation sensing and signaling and discuss new directions for future studies. 展开更多
关键词 abiotic stress sensing nutrient use efficiency heavy metal Ca2+signaling ROS signal transduction PHOSPHORYLATION transcription factor TRANSPORTER
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Esophageal cancer: A Review of epidemiology, pathogenesis, staging workup and treatment modalities 被引量:97
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作者 Kyle J Napier Mary Scheerer Subhasis Misra 《World Journal of Gastrointestinal Oncology》 SCIE CAS 2014年第5期112-120,共9页
Esophageal cancer is a serious malignancy with regards to mortality and prognosis. It is a growing health concern that is expected to increase in incidence over the next 10 years. Squamous cell carcinoma is the most c... Esophageal cancer is a serious malignancy with regards to mortality and prognosis. It is a growing health concern that is expected to increase in incidence over the next 10 years. Squamous cell carcinoma is the most common histological type of esophageal cancer worldwide, with a higher incidence in developing nations. With the increased prevalence of gastroesophageal reflux disease and obesity in developed nations, the incidence of esophageal adenocarcinoma has dramatically increased in the past 40 years. Esophageal cancer is staged according to the widely accepted TNM system. Staging plays an integral part in guiding stage specific treatment protocols and has a great impact on overall survival. Common imaging modalities used in staging include computed tomography, endoscopic ultrasound and positron emission tomography scans. Current treatment options include multimodality therapy mainstaysof current treatment include surgery, radiation and chemotherapy. Tumor markers of esophageal cancer are an advancing area of research that could potentially lead to earlier diagnosis as well as playing a part in assessing tumor response to therapy. 展开更多
关键词 Esophageal cancer Esophageal cancer staging Esophageal squamous cell carcinoma Esophageal adenocarcinoma SURGERY
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长期施肥下我国南方典型农田土壤的酸化特征 被引量:91
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作者 周晓阳 徐明岗 +1 位作者 周世伟 Colinet Gilles 《植物营养与肥料学报》 CAS CSCD 北大核心 2015年第6期1615-1621,共7页
【目的】阐明长期施肥下我国南方典型农田土壤的酸化特征,为合理施肥缓解农田土壤酸化提供科学依据。【方法】对湖南省典型农田土壤一水稻土和红壤上设置的32个长期监测点10年间的土壤pH及相关数据进行统计分析。【结果】从整体上看水... 【目的】阐明长期施肥下我国南方典型农田土壤的酸化特征,为合理施肥缓解农田土壤酸化提供科学依据。【方法】对湖南省典型农田土壤一水稻土和红壤上设置的32个长期监测点10年间的土壤pH及相关数据进行统计分析。【结果】从整体上看水稻土在长期施肥下未呈现明显酸化;在水旱轮作模式下的水稻土出现显著酸化,其pH平均下降速率为每年0.076是持续种稻模式的10倍。化学氮肥施用量的增加是水旱轮作下土壤酸化的重要因素之一,有机肥的施用对水稻土酸化无显著影响。红壤在常规施肥10 a期间pH呈明显的阶段性变化特征,施肥4-6 a与1-3a相比土壤pH下降了0.19个单位显著酸化;持续施肥至7-10 a红壤pH保持相对稳定。起始pH相对较高(pH〉6)的红壤长期施肥下出现极显著酸化,pH平均下降速率为每年0.075,与化肥氮施用量呈显著正相关;pH相对较低(pH 4-5)的红壤长期施肥下未显著酸化。【结论】我国南方地区长期施肥下,与持续种稻模式相比水旱轮作模式加速了水稻土的酸化,化学氮肥施用量的增加是导致其酸化的重要原因;起始pH相对较高(pH〉6)的红壤显著酸化化学氮肥用量增加导致其显著酸化。因此,控制和减少化学氮肥的用量是防止水旱轮作模式下土壤及红壤旱地进一步酸化的重要措施。 展开更多
关键词 长期施肥 土壤酸化 PH 水稻土 红壤
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基于正交拉丁方的数字图像置乱方法 被引量:39
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作者 李国富 Tie Xiaoyun 《北方工业大学学报》 2001年第1期14-16,26,共4页
以图象信息安全问题为背景 ,介绍了正交拉丁方用于图像置乱的理论基础 。
关键词 信息安全 拉丁方 正交拉丁方 数字图象置乱方法
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Restoring urbanization process in China in the 1990s by using non-radiance-calibrated DMSP/OLS nighttime light imagery and statistical data 被引量:56
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作者 HE Chunyang SHI Peijun +5 位作者 LI dinggang CHEN din PAN Yaozhong LI ding ZHUO Li Ichinose Toshiaki 《Chinese Science Bulletin》 SCIE EI CAS 2006年第13期1614-1620,共7页
Since current administrative unit-based urban land area statistical data in China lack enough spatial information, the urbanization process re- search at large scale cannot be effectively supported. Based on the curre... Since current administrative unit-based urban land area statistical data in China lack enough spatial information, the urbanization process re- search at large scale cannot be effectively supported. Based on the current administrative unit-based urban land area statistical data in China, a new approach to quickly and cheaply derive urban land information from the non-radiance-calibrated Defense Meteoro- logical Satellite Program/ Operational Linescan Sys- tem (DMSP/OLS) nighttime light imagery is pre- sented in this paper. With the new approach, the ur- ban pattern information in China in 1992, 1996 and 1998 was derived with the urbanization processes in China in the 1990s restored by using the non-ra- diance-calibrated DMSP/OLS nighttime imagery. The accuracy assessment based on the statistical data showed that the relative error between the derived total urban land area and the statistical data at na- tional scale was less than 2% in 1992, and less than 1% in 1996 and 1998, and the maximum relative er- ror at province scale do not exceed 10% with most of the provinces less than 3%. In addition, the urban patterns derived from the high-resolution Landsat TM imagery were compared with those from the DMSP/ OLS data. The results showed that the urban pattern characteristics derived from DMSP/OLS were basi-cally coincident with those from TM imagery with the total accuracy of about 80%. Thus it can be seen that our restored urbanization process in China in the 1990s by using the non-radiance DMSP/OLS night- time imagery can be accepted and can represent the actual urban development in China at that time on the whole. 展开更多
关键词 城市化 中国 DMSP/OLS 统计数据
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中国南方水稻土酸化演变特征及影响因素 被引量:55
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作者 周晓阳 周世伟 +1 位作者 徐明岗 Colinet Gilles 《中国农业科学》 CAS CSCD 北大核心 2015年第23期4811-4817,共7页
【目的】明确中国南方水稻土酸化特征及主要影响因素,为防控水稻土酸化提供理论依据。【方法】选择中国南方江苏、湖南、广东、广西、四川和云南6个省份(自治区)的20个水稻土长期定位监测点,统计分析水稻土pH演变特征及阶段性变化规律,... 【目的】明确中国南方水稻土酸化特征及主要影响因素,为防控水稻土酸化提供理论依据。【方法】选择中国南方江苏、湖南、广东、广西、四川和云南6个省份(自治区)的20个水稻土长期定位监测点,统计分析水稻土pH演变特征及阶段性变化规律,并探讨施肥量及土壤氮素含量对水稻土酸化的影响。【结果】1988—2013年25年间中国南方水稻土显著酸化,土壤pH下降0.59个单位,平均每年下降0.023个单位。水稻土酸化具有明显的阶段性特征,起始的14年中水稻土pH急速下降,平均每年可下降0.051个单位;近10年间,土壤pH趋于平稳。增施化肥特别是化学氮肥可导致水稻土酸化,二者与土壤pH均呈显著负相关关系(P<0.01),由此推算出化学氮肥每增施100 kg·hm-2,水稻土pH可下降0.65个单位。减少有机肥的施用也可引起水稻土酸化,有机肥施用量与土壤pH之间呈显著正相关关系,有机肥每减少100 kg·hm-2,水稻土pH下降0.51个单位。土壤全氮及碱解氮含量与pH间均呈极显著负相关关系,土壤全氮和碱解氮含量每增加100 mg·kg-1,水稻土pH约下降0.1个单位。【结论】在过去25年间,中国南方水稻土显著酸化,酸化具有明显的阶段性特征,施肥初期土壤pH显著降低。减少化学氮肥的施用和增施有机肥是控制水稻土酸化的重要措施。 展开更多
关键词 水稻土 酸化 长期施肥 氮肥 土壤PH
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Aggressive blood pressure treatment of hypertensive intracerebral hemorrhage may lead to global cerebral hypoperfusion:Case report and imaging perspective 被引量:50
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作者 Jose Gavito-Higuera Rakesh Khatri +2 位作者 Ihtesham A Qureshi Alberto Maud Gustavo J Rodriguez 《World Journal of Radiology》 CAS 2017年第12期448-453,共6页
Hypoperfusion injury related to blood pressure decrease in acute hypertensive intracerebral hemorrhage continues to be a controversial topic. Aggressive treatment is provided with the intent to stop the ongoing bleedi... Hypoperfusion injury related to blood pressure decrease in acute hypertensive intracerebral hemorrhage continues to be a controversial topic. Aggressive treatment is provided with the intent to stop the ongoing bleeding. However, there may be additional factors, including autoregulation and increased intracranial pressure, that may limit this approach. We present here a case of acute hypertensive intracerebral hemorrhage, in which aggressive blood pressure management to levels within the normal range led to global cerebral ischemia within multiple border zones. Global cerebral ischemia may be of concern in the management of hypertensive hemorrhage in the presence of premorbid poorly controlled blood pressure and increased intracranial pressure. 展开更多
关键词 Intracranial hemorrhage Neurocritial care Stroke management Perihematoma ischemia
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Cold-chain transportation in the frozen food industry may have caused a recurrence of COVID-19 cases in destination:Successful isolation of SARS-CoV-2 virus from the imported frozen cod package surface 被引量:49
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作者 Peipei Liu Mengjie Yang +9 位作者 Xiang Zhao Yuanyuan Guo Liang Wang Jing Zhang Wenwen Lei Weifang Han Fachun Jiang William J.Liu George F.Gao Guizhen Wu 《Biosafety and Health》 2020年第4期199-201,共3页
Coronavirus disease 2019(COVID-19)pandemic has spread in 220 countries/regions towreak havoc to human beings around theworld.At present,the second wave of COVID-19 has begun in many European countries.The complete con... Coronavirus disease 2019(COVID-19)pandemic has spread in 220 countries/regions towreak havoc to human beings around theworld.At present,the second wave of COVID-19 has begun in many European countries.The complete control of COVID-19 is very urgent.Although China quickly brought the virus under control,there have been eight sporadic outbreaks in China since then.Both in Xinfadi of Beijing and Dalian outbreak of COVID-19,environmental swab samples related to imported cold chain food were tested nucleic acid positive for SARS-CoV-2.In this outbreak in Qingdao,we directly isolated SARS-CoV-2 from the cod outer package's surface swab samples.This is the first time worldwide,SARS-CoV-2 were isolated from the imported frozen cod outer package's surface,which showed that imported frozen food industry could import SARS-CoV-2 virus. 展开更多
关键词 COVID-19 SARS-CoV-2 Cod outer package Frozen food
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Anterior muscle sparing approach for total hip arthroplasty 被引量:47
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作者 Joseph T Moskal Susan G Capps John A Scanelli 《World Journal of Orthopedics》 2013年第1期12-18,共7页
The purpose of this review is to examine the validity of positive claims regarding the direct anterior approach(DAA) with a fracture table for total hip arthroplasty. Recent literature regarding the DAA was searched a... The purpose of this review is to examine the validity of positive claims regarding the direct anterior approach(DAA) with a fracture table for total hip arthroplasty. Recent literature regarding the DAA was searched and specific claims investigated including improved early outcomes, speed of recovery, component placement, dislocation rates, and complication rates. Recent literature is positive regarding the effects of total hip arthroplasty with the anterior approach. While the data is not definitive at present, patients receiving the anterior approach for total hip arthroplasty tend to recover more quickly and have improved early outcomes. Component placement with the anterior approach is more often in the "safe zone" than with other approaches. Dislocation rates tend to be less than 1% with the anterior approach. Complication rates vary widely in the published literature. A possible explanation is that the varianceis due to surgeon and institutional experience with the anterior approach procedure. Concerns remain regarding the "learning curve" for both surgeons and institutions. In conclusion, it is not a matter of should this approach be used, but how should it be implemented. 展开更多
关键词 Total HIP ARTHROPLASTY ANTERIOR APPROACH HIP ARTHRITIS Joint replacement
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ETFE薄膜的材料性能及其工程应用综述 被引量:37
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作者 胥传喜 陈楚鑫 钱若军 《钢结构》 2003年第6期1-4,共4页
就ETFE薄膜的材料性能、在膜结构工程中的应用形式、ETFE气垫的工作原理、膜材连接方法。
关键词 膜结构 膜材料 ETFE气垫 ETFE薄膜
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Micro-structural evolution and their effects on physical properties in different types of tectonically deformed coals 被引量:45
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作者 Yiwen Ju Kray Luxbacher +4 位作者 Xiaoshi Li Guochang Wang Zhifeng Yan Mingming Wei Liye Yu 《International Journal of Coal Science & Technology》 EI CAS 2014年第3期364-375,共12页
The macromolecular structure of tectonically deformed coals(TDC)may be determined by the deformation mechanisms of coal.Alterations of the macromolecular structure change the pore structure of TDC and thereby impact p... The macromolecular structure of tectonically deformed coals(TDC)may be determined by the deformation mechanisms of coal.Alterations of the macromolecular structure change the pore structure of TDC and thereby impact physical properties such as porosity and permeability.This study focuses on structure and properties of TDC from the Huaibei and Huainan coal mining areas of southern North China.Relationships between the macromolecular structure and the pore structure of TDC were analyzed using techniques such as X-ray diffraction,high-resolution transmission electron microcopy,and the low-temperature nitrogen adsorption.The results indicated that the directional stress condition can cause the arrangement of basic structural units(BSU)more serious and closer.And,the orientation is stronger in ductile deformed coal than in brittle deformed coal.Tectonic deformation directly influences the macromolecular structure of coal and consequently results in dynamic metamorphism.Because the size of BSU in brittle deformed coal increases more slowly than in ductile deformed coal,frictional heating and stress-chemistry of shearing areas might play a more important role,locally altering coal structure under stress,in brittle deformed coal.Strain energy is more significant in increasing the ductile deformation of coal.Furthermore,mesopores account for larger percentage of the nano-scale pore volume in brittle deformed coals,while mesopores volume in ductile deformed coal diminishes rapidly along with an increase in the proportion of micropores and sub-micropores.This research also approved that the deformations of macromolecular structures change nano-scale pore structures,which are very important for gas adsorption and pervasion space for gas.Therefore,the exploration and development potential of coal bed methane is promising for reservoirs that are subjected to a certain degree of brittle deformation(such as schistose structure coal,mortar structure coal and cataclastic structure coal).It also holds promise for TDC resulting from 展开更多
关键词 Tectonically deformed coals Formation mechanisms Macromolecular structure Pore structure Micro-structured evolution Coal bed methane
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野生扬子鳄种群及栖息地现状研究 被引量:35
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作者 丁由中 王小明 +4 位作者 何利军 邵民 谢万树 Thorbjarnarson B John Mc Murry T Scott 《生物多样性》 CAS CSCD 2001年第2期102-108,共7页
1999年 7~ 8月及 2 0 0 0年 8~ 9月 ,利用GPS、激光测距仪等 ,采用夜间灯光照射计数方法 ,对有野生扬子鳄(Alligatorsinensis)存在的安徽省宣州、泾县、广德、郎溪、南陵等 5县市的 2 6个地点进行了调查 ,包括扬子鳄国家级自然保护区... 1999年 7~ 8月及 2 0 0 0年 8~ 9月 ,利用GPS、激光测距仪等 ,采用夜间灯光照射计数方法 ,对有野生扬子鳄(Alligatorsinensis)存在的安徽省宣州、泾县、广德、郎溪、南陵等 5县市的 2 6个地点进行了调查 ,包括扬子鳄国家级自然保护区的 13个指定保护点。结果发现 :目前野生扬子鳄主要生存在第一类栖息地 (1999年 5 0 .7%、2 0 0 0年40 .0 % ) ,面积为 17.38hm2 ;其他两类栖息地的野生扬子鳄分布比率较小 (各为 1999年 2 4.0 %、2 0 0 0年 30 .9%、1999年 2 5 .3%、2 0 0 0年 2 9.1% ) ,面积分别为 2 2 .0 4hm2 、19.0 3hm2 。两年的平均生态密度分别为 1.2 8条 /hm2和 1.79条 /hm2 ,野生扬子鳄种群数量为 145条。其种群已明显分为至少 18个数量不等且相互隔离的地方种群。建议恢复足够大的栖息地 ,并放饲养鳄于其中以重新建立有效野生种群。 展开更多
关键词 野生扬子鳄 种群数量 栖息地
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Improved measurement of electron antineutrino disappearance at Daya Bay 被引量:38
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作者 安丰鹏 安琪 +151 位作者 白景芝 A.B.Balantekin H.R.Band W.Beriguete M.Bishai S.Blyth R.L.Brown 曹国富 曹俊 R.Carr W.T.Chan 常劲帆 Y.Chang C.Chasman 陈和生 H.Y.Chen 陈申见 陈少敏 陈潇聪 陈晓辉 陈晓苏 陈羽 陈义学 J.J.Cherwinka 朱明中 J.P.Cummings 邓子艳 丁雅韵 M.V.Diwan E.Draeger 杜小峰 D.Dwyer W.R.Edwards S.R.Ely 方绍东 付金煜 付在伟 葛良全 R.L.Gi11 M.Gonchar 龚光华 宫辉 Y.A.Gornushkin 顾文强 关梦云 郭新恒 R.W.Hackenburg R.L.Hahn S.Hans 郝慧峰 何苗 贺青 K.M.Heeger 衡月昆 P.Hinrichs Y.K.Hor Y.B.Hsiung B.z.Hu 胡涛 黄翰雄 H.z.Huang 黄性涛 P.Huber V.Issakov z.Isvan D.E.Jaffe S.Jetter 季筱璐 季向盼 姜海静 焦健斌 R.A.Johnson 康丽 S.H.Kettell M.Kramer 关健强 郭文伟 郭人能 C.Y.Lai 赖万昌 W.H.Lai K.Lau L.Lebanowski J.Lee 雷瑞霆 R.Leitner 梁干庄 梁嘉怡 C.A.Lewis 李飞 李高嵩 李秋菊 李卫东 李小波 李小男 李学潜 李仪 李志斌 梁昊 林政儒 C.L.Lin S.K.Lin 林延畅 凌家杰 J.M.Link L.Littenberg B.R.Littlejohn D.W.Liu 刘金昌 刘江来 刘颖彪 陆昌国 路浩奇 陆永康 K.B.Luk 马秋梅 马续波 马骁妍 马宇蒨 K.T.McDonald M.C.McFarlane R.D.McKeown Y.Meng D.Mohapatra Y.Nakajima J.Napolitano D.Naumov I.Nemchenok 倪浩然 W.K.Ngai 聂阳波 宁哲 J.P.Ochoa-Ricoux A.Olshevski S.Patton V.Pec J.C.Peng L.E.Piilonen L.Pinsky 潘振声 齐法制 祁鸣 钱鑫 N.Raper 任杰 R.Rosero B.Roskovec 阮锡超 邵贝贝 师恺 H.Steiner 孙� 《Chinese Physics C》 SCIE CAS CSCD 2013年第1期1-20,共20页
We report an improved measurement of the neutrino mixing angle θ13 from the Daya Bay Reactor Neutrino Experiment. We exclude a zero value for sin22θ13 with a significance of 7.7 standard deviations. Electron antineu... We report an improved measurement of the neutrino mixing angle θ13 from the Daya Bay Reactor Neutrino Experiment. We exclude a zero value for sin22θ13 with a significance of 7.7 standard deviations. Electron antineutrinos from six reactors of 2.9 GWm th were detected in six antineutrino detectors deployed in two near (flux-weighted baselines of 470 m and 576 m) and one far (1648 m) underground experimental halls. Using 139 days of data, 28909 (205308) electron antineutrino candidates were detected at the far hall (near halls). The ratio of the observed to the expected number of antineutrinos assuming no oscillations at the far hall is 0.944± 0.007(stat.) ± 0.003(syst.). An analysis of the relative rates in six detectors finds sin22θ13=0.089± 0.010(stat.)±0.005(syst.) in a three-neutrino framework. 展开更多
关键词 neutrino oscillation neutrino mixing REACTOR Daya Bay
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Phosphorus Changes and Sorption Characteristics in a Calcareous Soil Under Long-Term Fertilization 被引量:36
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作者 GUO Sheng-Li DANG Ting-Hui HAO Ming-De 《Pedosphere》 SCIE CAS CSCD 2008年第2期248-256,共9页
Knowledge of phosphorus (P) behavior in long-term fertilized soils is essential for programming fertilization practices and for sustaining environmental quality. The long-term (1984-1997) effects of various fertil... Knowledge of phosphorus (P) behavior in long-term fertilized soils is essential for programming fertilization practices and for sustaining environmental quality. The long-term (1984-1997) effects of various fertilization treatments on P changes and sorption isotherms as well as the relationship of soil properties to P sorption and P forms were evaluated in an Ustic Isohumisol, a calcareous soil, on the Loess Plateau, China. Compared to 1984, after 13 years of crop production, total soil P in the no-P treatments (control and N treatment) decreased by 5%-7%, but in the phosphorus fertilizer alone (P), nitrogen and phosphorus fertilizers in combination (NP), manure alone (M), and nitrogen and phosphorus fertilizers and manure in combination (NPM) treatments, it increased by 22%, 19%, 28%, and 58%, respectively. Residual fertilizer P was found mainly in NH4Ac-soluble P (Cas-P), followed by NaHCO3-soluble P (NaHCO3-P), and NH4F-soluble P (Al-P). Phosphorus sorption in the soils with different fertilization practices fit the Langmuir equations. Phosphorus sorption capacity in the no-P treatments increased, whereas it decreased in the P-included treatments (P, NP, and NPM treatments). Phosphorus sorption maximum (Qm) was significantly and negatively correlated to inorganic P including NaHCO3-P, Cas-P, NaOH-Na2CO3-soluble P (Fe-P), and Al-P (P ≤ 0.01). Moreover, long-term fertilization increased soil organic carbon in the NP, M, and NPM treatments and decreased pH in the NP and NPM treatments. Thus, the ability of the soil to release sorbed P to the environment increased under long-term P fertilization. 展开更多
关键词 calcareous soil long-term fertilization P accumulation P sorption P transformations
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Second harmonic generation in a high-Q lithium niobate microresonator fabricated by femtosecond laser micromachining 被引量:36
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作者 LIN JinTian XU YingXin +5 位作者 FANG ZhiWei WANG Min WANG NengWen QIAO LingLing FANG Wei CHENG Ya 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS CSCD 2015年第11期50-54,共5页
We report on second harmonic generation(SHG) in on-chip high-Q(>105) lithium niobate(Li Nb O3, LN) microresonators fabricated by femtosecond laser micromachining. We examine the efficiency of SHG with either a cont... We report on second harmonic generation(SHG) in on-chip high-Q(>105) lithium niobate(Li Nb O3, LN) microresonators fabricated by femtosecond laser micromachining. We examine the efficiency of SHG with either a continuous-wave(CW) or an ultrashort pulsed pump laser. The normalized conversion efficiencies of SHG obtained with the CW and pulsed pump lasers are measured to be 1.35×10?5 m W?1 and 2.30×10?6 m W?1, respectively. 展开更多
关键词 second harmonic generation femtosecond laser micromachining lithium niobate microresonator
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模糊AHP方法在产品绿色模块化设计中的应用 被引量:24
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作者 李方义 刘钢 +2 位作者 汪劲松 段广洪 H.C.Zhang 《中国机械工程》 CAS CSCD 北大核心 2000年第9期997-1000,共4页
绿色设计和绿色制造是制造业实施可持续发展的关键技术。在绿色产品设计开发过程中采用模块化技术 ,易于增加产品的材料相容性、可维护性、可拆卸及可回收性等。总结了模块化方法在产品绿色设计中的应用特点 ,考虑环境问题应引进的模块 ... 绿色设计和绿色制造是制造业实施可持续发展的关键技术。在绿色产品设计开发过程中采用模块化技术 ,易于增加产品的材料相容性、可维护性、可拆卸及可回收性等。总结了模块化方法在产品绿色设计中的应用特点 ,考虑环境问题应引进的模块 ,产品实施模块化中应主要考虑的环境目标等 ;提出了一种应用于离散型机电产品多目标模块化分析的初步框架 ,对利用模糊图论和 AHP方法解决机电产品绿色设计决策的多目标。 展开更多
关键词 绿色设计 模块化方法 关联度 模糊图 机电产品
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淮安楚州居民饮食、行为因素与食管癌关系的病例-对照研究 被引量:24
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作者 谢莹 孙桂菊 +9 位作者 胡旭 王少康 开海涛 崔永生 胡永祯 张豪 蔡青松 王泽民 唐耘天 王加生 《卫生研究》 CAS CSCD 北大核心 2005年第4期479-480,共2页
目的探讨淮安市楚州区居民的饮食、行为因素与食管癌高发的关系。方法进行1∶1配对病例-对照研究,对107例食管癌病例及对照进行问卷调查,采用条件Logistic回归对所获资料进行统计分析。结果进食速度快、喜食咸辣、腌制品、十年前粮食霉... 目的探讨淮安市楚州区居民的饮食、行为因素与食管癌高发的关系。方法进行1∶1配对病例-对照研究,对107例食管癌病例及对照进行问卷调查,采用条件Logistic回归对所获资料进行统计分析。结果进食速度快、喜食咸辣、腌制品、十年前粮食霉变可能是食管癌的危险因素;而饮茶和摄入豆制品则具有保护作用。结论食管癌是多种环境因素对具有不同遗传素质的个体长期反复作用的结果,宜采取综合性防治措施。 展开更多
关键词 食管癌 病例对照研究 危险因素
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Engineering Non-transgenic Gynoecious Cucumber Using an Improved Transformation Protocol and Optimized CRISPR/Cas9 System 被引量:34
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作者 Bowen Hu Dawei Li +6 位作者 Xin Liu Jingjing Qi Dongli Gao Shuqiao Zhao Sanwen Huang Jinjing Sun Li Yang 《Molecular Plant》 SCIE CAS CSCD 2017年第12期1575-1578,共4页
Dear Editor,Gynoecism has been extensively exploited in cucumber breeding. The utilization of a gynoecious line permits earlier pro- duction of hybrids, higher yield, and more concentrated fruit set. In addition, the ... Dear Editor,Gynoecism has been extensively exploited in cucumber breeding. The utilization of a gynoecious line permits earlier pro- duction of hybrids, higher yield, and more concentrated fruit set. In addition, the utilization of a gynoecious line eliminates the need for hand emasculation and reduces the labor cost of crossing (Robinson, 2000). Therefore, the development of gynoeoious inbred lines is instrumental for cucumber breeding. Gynoecious inbreds can be produced by selection from crosses of monoecious inbreds, or can arise spontaneously from natural variation. However, both methods have disadvantages. For instance, the time-consuming and laborious process of crossing can also lead to the introduction of undesirable traits, 展开更多
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时间序列分析法在香港结核病预测中的应用 被引量:33
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作者 刘刚 唐宋 孙文杰 《中国卫生统计》 CSCD 北大核心 2012年第2期226-228,共3页
目的阐述ARIMA模型拟合时间序列的方法和步骤,并将其应用于结核病的预测,为传染病预警系统提供决策依据。方法利用SPSS统计软件对香港1997年到2008年结核病数据进行基本趋势分析并检验数据的平稳性,对平稳处理后的时间序列构建ARIMA模型... 目的阐述ARIMA模型拟合时间序列的方法和步骤,并将其应用于结核病的预测,为传染病预警系统提供决策依据。方法利用SPSS统计软件对香港1997年到2008年结核病数据进行基本趋势分析并检验数据的平稳性,对平稳处理后的时间序列构建ARIMA模型,并对所建立的模型进行相关性检验,预测出未来一年的数据。结果通过对结核病的预测,相对误差在3%左右,预测效果较为可靠。结论在结核病的近期预测中引入时间序列的ARIMA模型分析方法 ,能够对结核病的预测产生积极的指导意义。 展开更多
关键词 ARIMA模型 时间序列 结核病
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