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关于上博楚简《君人者何必安哉》“云■”释读的一点意见——为纪念朱德熙先生诞辰百年而作 被引量:1
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作者 李家浩 《出土文献》 2020年第4期64-67,156-157,共6页
上海博物馆藏楚简《君人者何必安哉》有甲、乙两本,内容是范戌向楚王进诛,其中谈到楚灵王"乾溪云■"。本文根据史书记载楚灵王死于乾溪,认为"云■"二字是表示死亡的意思,应该读为"殒命",并且对它们之间... 上海博物馆藏楚简《君人者何必安哉》有甲、乙两本,内容是范戌向楚王进诛,其中谈到楚灵王"乾溪云■"。本文根据史书记载楚灵王死于乾溪,认为"云■"二字是表示死亡的意思,应该读为"殒命",并且对它们之间的通假关系加以说明。 展开更多
关键词 上博楚简 云■ 殒命
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沈长云先生在先秦史研究领域的重要贡献
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作者 李禹阶 《河北师范大学学报(哲学社会科学版)》 2024年第3期1-8,共8页
20世纪80年代起,我国先秦史研究领域进入一个思想解放、鼎故革新的阶段。沈长云先生伴随这一历程,通过求实创新的治学精神、独具一格的学术视野和科学合理的研究方法,对先秦历史的诸多重要问题提出了颇为深刻的学术观点,为先秦史研究做... 20世纪80年代起,我国先秦史研究领域进入一个思想解放、鼎故革新的阶段。沈长云先生伴随这一历程,通过求实创新的治学精神、独具一格的学术视野和科学合理的研究方法,对先秦历史的诸多重要问题提出了颇为深刻的学术观点,为先秦史研究做出了重要贡献。在国家起源等重要问题上,沈先生既遵循马克思历史唯物主义的基本原则,又主张理论与实际结合,同时还结合塞维斯“酋邦”理论和最新考古发现。作为中国古代“无奴派”早期代表性学者,沈先生提出中国古代不同于希腊、罗马,虽存在一定数量的奴隶制经济,但并非以奴隶制为主。相比五种社会形态说,中国古代社会演进道路更接近亚细亚生产方式。我国直接由血缘氏族组织进入早期国家形态,是氏族、部落首领由“公仆”蜕变为统治阶层,这种“家国同构”的权力结构成为帝制时代的君主专制主义的基础。在三代族源考索方面,沈先生坚持认为夏代是存在的,且夏族兴起于古河济地区,商族起源于晋中地区,周人、夏人没有族属方面的传承关系,周族起源于白狄。沈长云先生注重古典文献的考订、甄别,他参与点校的《国语集解》是海内外学者研究春秋史的重要参考文献。 展开更多
关键词 沈长云 先秦史 求实创新 重要贡献
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Boehmeria nivea var. strigosa (Urticaceae), a new variety from Southwest China 被引量:1
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作者 ZHAO Ying Richard I.MILNE +2 位作者 LI Zhipeng Amos KIPKOECH WU Zengyuan 《广西植物》 CAS CSCD 北大核心 2024年第9期1617-1624,I0001-I0006,共14页
Boehmeria nivea var.strigosa Zeng Y.Wu&Y.Zhao,a new variety of B.nivea(Urticaceae)from Southwest China,is here described based on evidence from morphology and molecular phylogeny.This new variety is mainly charact... Boehmeria nivea var.strigosa Zeng Y.Wu&Y.Zhao,a new variety of B.nivea(Urticaceae)from Southwest China,is here described based on evidence from morphology and molecular phylogeny.This new variety is mainly characterized by its green abaxial leaf blade,partly connate stipules,and densely patent strigose hairs on stems and potioles.The phylogenetic analysis based on rbc L,nrDNA and rbc L+nrDNA datasets,revealed that all individuals of B.nivea var.strigosa formed a monophyletic group.The conservation status of B.nivea var.strigosa is assessed as“Near Threatened”(NT)according to IUCN evaluation criteria.The discovery of this new variety is not only crucial for the taxonomy of ramie,but also provides reference for the exploration and utilization of ramie. 展开更多
关键词 Boehmeria nivea MORPHOLOGY molecular phylogeny new variety Southwest China YUNNAN
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Cosmic Ray-driven Bioenergetics for Life in Molecular Clouds
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作者 FENG Lei 《天文学报》 CAS CSCD 北大核心 2024年第6期26-31,共6页
According to models such as panspermia or the Nebula-Relay hypothesis,the ancestors of life on Earth once lived in molecular clouds.Then what are the energy source and bioenergetics for such lifeforms?A new bioenerget... According to models such as panspermia or the Nebula-Relay hypothesis,the ancestors of life on Earth once lived in molecular clouds.Then what are the energy source and bioenergetics for such lifeforms?A new bioenergetic mechanism powered by cosmic ray ionization of hydrogen molecules is proposed and its relation with the origin of chemiosmosis is also discussed in this paper.Based on this mechanism,the Last Universal Common Ancestor may be a type of lifeform that utilizes hydrogen molecules as donors of electron transport chains. 展开更多
关键词 ASTROBIOLOGY ASTROCHEMISTRY interstellar medium(ISM) NEBULAE cosmic ray
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Research on BIM Model Reshaping Method Based on 3D Point Cloud Recognition
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作者 SHI Jin-yu YU Xian-feng +1 位作者 SI Zhan-jun ZHANG Ying-xue 《印刷与数字媒体技术研究》 CAS 北大核心 2024年第4期125-135,共11页
In view of the limitations of traditional measurement methods in the field of building information,such as complex operation,low timeliness and poor accuracy,a new way of combining three-dimensional scanning technolog... In view of the limitations of traditional measurement methods in the field of building information,such as complex operation,low timeliness and poor accuracy,a new way of combining three-dimensional scanning technology and BIM(Building Information Modeling)model was discussed.Focused on the efficient acquisition of building geometric information using the fast-developing 3D point cloud technology,an improved deep learning-based 3D point cloud recognition method was proposed.The method optimised the network structure based on RandLA-Net to adapt to the large-scale point cloud processing requirements,while the semantic and instance features of the point cloud were integrated to significantly improve the recognition accuracy and provide a precise basis for BIM model remodeling.In addition,a visual BIM model generation system was developed,which systematically transformed the point cloud recognition results into BIM component parameters,automatically constructed BIM models,and promoted the open sharing and secondary development of models.The research results not only effectively promote the automation process of converting 3D point cloud data to refined BIM models,but also provide important technical support for promoting building informatisation and accelerating the construction of smart cities,showing a wide range of application potential and practical value. 展开更多
关键词 3D point cloud RandLA-Net network BIM model OSG engine
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3D Ice Shape Description Method Based on BLSOM Neural Network
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作者 ZHU Bailiu ZUO Chenglin 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2024年第S01期70-80,共11页
When checking the ice shape calculation software,its accuracy is judged based on the proximity between the calculated ice shape and the typical test ice shape.Therefore,determining the typical test ice shape becomes t... When checking the ice shape calculation software,its accuracy is judged based on the proximity between the calculated ice shape and the typical test ice shape.Therefore,determining the typical test ice shape becomes the key task of the icing wind tunnel tests.In the icing wind tunnel test of the tail wing model of a large amphibious aircraft,in order to obtain accurate typical test ice shape,the Romer Absolute Scanner is used to obtain the 3D point cloud data of the ice shape on the tail wing model.Then,the batch-learning self-organizing map(BLSOM)neural network is used to obtain the 2D average ice shape along the model direction based on the 3D point cloud data of the ice shape,while its tolerance band is calculated using the probabilistic statistical method.The results show that the combination of 2D average ice shape and its tolerance band can represent the 3D characteristics of the test ice shape effectively,which can be used as the typical test ice shape for comparative analysis with the calculated ice shape. 展开更多
关键词 icing wind tunnel test ice shape batch-learning self-organizing map neural network 3D point cloud
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“道德”与“有情”:从《水浒传》到《石秀》
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作者 刘川鄂 杨萌 《长江学术》 CSSCI 2023年第2期47-63,共17页
施蛰存的历史小说《石秀》,运用精神分析法对传统文本进行了现代性反叛,解构了传统文本中的儒家礼教和伦理道德,在中国现代文学中具有开山辟疆的作用。《水浒传》中石秀是“路见不平拔刀相助”、智勇双全的英雄好汉,是“忠义”伦理道德... 施蛰存的历史小说《石秀》,运用精神分析法对传统文本进行了现代性反叛,解构了传统文本中的儒家礼教和伦理道德,在中国现代文学中具有开山辟疆的作用。《水浒传》中石秀是“路见不平拔刀相助”、智勇双全的英雄好汉,是“忠义”伦理道德的捍卫者。而施蛰存以“俄狄浦斯情结”来构建石秀形象,使其对义嫂产生不伦之恋,给予这种隐秘情欲以正当性、合理性,并不作善恶道德评价,是对复杂人性的展示和深挖。《水浒传》将潘巧云贬低、丑化为恶毒淫妇,是“贞节”伦理道德的背叛者,而《石秀》中潘巧云是热情爽朗、多情风流的美艳妇人,并体现出都市新女性的特质。《水浒传》中杨雄护兄弟,斩淫妇,是“忠义”伦理道德的践行者,而《石秀》却凸显杨雄杀妻的盲从和麻木,以此揭露封建礼教对人性的桎梏和扭曲。从《水浒传》到《石秀》单一的道德文本位移为丰富的人性文本,以三种形态展示了“有情”与“道德”的激烈冲撞下复杂多样的人性,体现了中国现代文学超越古代小说单一、道德化的人物塑形去建构人性。 展开更多
关键词 施蛰存 石秀 潘巧云 杨雄 俄狄浦斯情结
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云南白药胶囊在骨折术后疼痛中的临床应用
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作者 张柏娥 刘峻宇 +4 位作者 张天财 周宏斌 张祥伟 赵剑飞 孙敏 《辽宁中医杂志》 CAS 2023年第6期115-119,共5页
目的评价云南白药胶囊缓解骨折术后疼痛的有效性及安全性。方法采用随机、双盲双模拟、阳性药平行对照的方法,筛选90例受试者按1∶1比例随机分配至试验组和对照组,分别在基线期(术前6 h内)和术后(6±1)h、(24±2)h、(48±2)... 目的评价云南白药胶囊缓解骨折术后疼痛的有效性及安全性。方法采用随机、双盲双模拟、阳性药平行对照的方法,筛选90例受试者按1∶1比例随机分配至试验组和对照组,分别在基线期(术前6 h内)和术后(6±1)h、(24±2)h、(48±2)h、(72±2)h、(168±48)h观察患者症状,运用疼痛视觉模拟(VAS)评分、患者整体印象变化量表(PGIC量表)以及麦吉尔疼痛量表(McGiLL量表)对其疼痛进行有效性评价。结果通过统计分析发现,受试者服药后各项评分均有所降低,表明云南白药胶囊能够改善术后疼痛以及因疼痛带来的负面情绪,且随术后康复时间的推移[术后(48±2)h],云南白药胶囊与塞来昔布胶囊镇痛效果相当。结论云南白药胶囊缓解骨折术后疼痛安全有效。 展开更多
关键词 云南白药胶囊 骨折术后 疼痛 临床研究
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复配乳液聚合物水泥防水涂料防护效果研究
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作者 吕格云 付弯弯 +4 位作者 卢雨婷 周薇 刘杰胜 彭浩 徐闫 《湖北科技学院学报》 2023年第4期140-149,共10页
本文以丙烯酸酯乳液和氯丁橡胶乳液复配的方法制备聚合物水泥防水涂料,以解决单一聚合物乳液水泥防水涂料在应用过程中易开裂、柔性不足等问题。将其涂覆于水泥砂浆试块表面,探讨了涂层对氯盐侵蚀、硫酸盐侵蚀、冻融循环、自然环境侵蚀... 本文以丙烯酸酯乳液和氯丁橡胶乳液复配的方法制备聚合物水泥防水涂料,以解决单一聚合物乳液水泥防水涂料在应用过程中易开裂、柔性不足等问题。将其涂覆于水泥砂浆试块表面,探讨了涂层对氯盐侵蚀、硫酸盐侵蚀、冻融循环、自然环境侵蚀下水泥砂浆试块质量、抗压强度的影响,分析了涂层对试块的防护效果。结果显示涂层水泥砂浆试块均无开裂、剥落现象,试块的质量损失率、抗压强度损失率均较小。采用复配乳液并添加外加剂制得涂层对水泥砂浆试块的防护效果最优,试块在氯盐、硫酸盐侵蚀180天、冻融循环100次后的抗压强度损失率分别为9.45%、10.84%、12.16%,自然环境侵蚀120天后,试块抗压强度可保持为29.80MPa远高于无涂层试块。还以其中防护效果最优配方制备聚合物水泥防水涂料,探讨了涂层涂覆方法对自然环境侵蚀下涂层水泥砂浆试块抗压强度的影响。结果显示固定涂层厚度,分多次涂覆制得涂层更致密,交叉涂覆方法制得涂层厚度更均匀,沿十字交叉方向分三次涂覆制得涂层对水泥砂浆试块的防护效果更优。 展开更多
关键词 聚合物水泥防水涂料 防水涂料 建筑防水 防护效果
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Extraction of lithium from lepidolite using chlorination roasting-water leaching process 被引量:23
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作者 颜群轩 李新海 +5 位作者 王志兴 王接喜 郭华军 胡启扬 彭文杰 伍习飞 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2012年第7期1753-1759,共7页
Chlorination roasting followed by water leaching process was used to extract lithium from lepidolite.The microstructure of the lepidolite and roasted materials were characterized by X-ray diffraction(XRD).Various pa... Chlorination roasting followed by water leaching process was used to extract lithium from lepidolite.The microstructure of the lepidolite and roasted materials were characterized by X-ray diffraction(XRD).Various parameters including chlorination roasting temperature,time,type and amount of chlorinating agents were optimized.The conditional experiments indicate that the best mass ratio of lepidolite to NaCl to CaCl2 is 1:0.6:0.4 during the roasting process.The extraction of lithium reaches peak value of 92.86% at 880 °C,potassium,rubidium,and cesium 88.49%,93.60% and 93.01%,respectively.The XRD result indicates that the major phases of the product after roasting lepidolite with mixture of chlorinating agents(CaCl2 and NaCl) are SiO2,CaF2,KCl,CaSiO3,CaAl2Si2O8,NaCl and NaAlSi3O8. 展开更多
关键词 LEPIDOLITE LITHIUM chlorination roasting water leaching
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Prediction of rock burst classification using cloud model with entropy weight 被引量:29
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作者 周科平 林允 +2 位作者 邓红卫 李杰林 刘传举 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2016年第7期1995-2002,共8页
The method of cloud model with entropy weight was adopted for the prediction of rock burst classification. Some main factors of rock burst including the uniaxial compressive strength (σc), the tensile strength (σ... The method of cloud model with entropy weight was adopted for the prediction of rock burst classification. Some main factors of rock burst including the uniaxial compressive strength (σc), the tensile strength (σt), the tangential stress (σθ), the rock brittleness coefficient (σc/σt), the stress coefficient (σθ /σc) and the elastic energy index (Wet) are chosen to establish evaluation index system. The entropy?cloud model and criterion are obtained through 209 sets of rock burst samples from underground rock projects. The sensitivity of indicators is analyzed and 209 sets of rock burst samples are discriminated by this model. The discriminant results of the entropy-cloud model are compared with those of Bayes, KNN and RF methods. The results show that the sensitivity order of those factors from high to low is σ_θ /σ_c, σ_θ, W_(ct), σ_c/σ_t, σ_t, σ_c, and the entropy-cloud model has higher accuracy than Bayes, K-Nearest Neighbor algorithm (KNN) and Random Forest (RF) methods. 展开更多
关键词 rock burst PREDICTION cloud model entropy weight sensitivity
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Assessment of Genetic Diversity of Yunnan,Tibetan,and Xinjiang Wheat Using SSR Markers 被引量:25
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作者 王海燕 王秀娥 +1 位作者 陈佩度 刘大钧 《Journal of Genetics and Genomics》 SCIE CAS CSCD 北大核心 2007年第7期623-633,共11页
A total of 206 SSR (Simple Sequence Repeats) primer pairs were used to detect genetic diversity in 52 accessions of three unique wheat varieties of western China. A total of 488, 472, and 308 allelic variants were d... A total of 206 SSR (Simple Sequence Repeats) primer pairs were used to detect genetic diversity in 52 accessions of three unique wheat varieties of western China. A total of 488, 472, and 308 allelic variants were detected in 31 Yunnan, 15 Tibetan and 6 Xinjiang wheat accessions with an average of PIC values 0.2764, 0.3082, and 0.1944, respectively. Substantial differences in allelic polymorphisms were detected by SSR markers in all the 21 chromosomes, the 7 homoeologous groups, and the three genomes (A, B, and D) in Yunnan, Tibetan, and Xinjiang wheat. The highest and lowest allelic polymorphisms in all the 21 chromosomes were observed in 3B and 1D chromosomes, respectively. The lowest and highest allelic polymorphisms among the seven homoeologous groups was observed in 6 and 3 homoeologous groups, respectively. Among the three genomes, B genome showed the highest, A the intermediate, and D the lowest allelic polymorphism. The genetic distance (GD) indexes within Yunnan, Tibetan, and Xinjiang wheat, and between different wheat types were calculated. The GD value was found to be much higher within Yunnan and Tibetan wheat than within Xinjiang wheat, but the GD value between Yunnan and Tibetan wheat was lower than those between Yunnan and Xinjiang wheat, and between Tibetan and Xinjiang wheat. The cluster analysis indicated a closer relationship between Yunnan and Tibetan wheat than that between Yunnan and Xinjiang wheat or between Tibetan and Xinjiang wheat. 展开更多
关键词 Yunnan wheat Tibetan wheat Xinjiang wheat genetic diversity SSR markers
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Kinetics of extracting magnesium from mixture of calcined magnesite and calcined dolomite by vacuum aluminothermic reduction 被引量:7
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作者 傅大学 冯乃祥 +2 位作者 王耀武 彭建平 狄跃忠 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第3期839-847,共9页
The vacuum aluminothermic reduction of the mixture of calcined magnesite and calcined dolomite was studied. An isothermal reduction method satisfying the vacuum aluminothermic reduction was proposed. The experiments w... The vacuum aluminothermic reduction of the mixture of calcined magnesite and calcined dolomite was studied. An isothermal reduction method satisfying the vacuum aluminothermic reduction was proposed. The experiments were carried out at 4 Pa. The results indicate that the reduction rate is increased with increasing temperature, content of aluminum and pellet forming pressure. The XRD patterns of pellets at different reduction stages confirm that the reduction process can be roughly classified into three stages:the formation of MgAl2O4, and Ca12Al14O33 phases;the phase transformation from MgAl2O4 and C12A7 to CaAl2O4;the formation of CaAl4O7 phase. The experimental data were divided into three parts according to the kinetic models. The apparent activation energies of the three parts were determined to be 98.2, 133.0 and 223.3 kJ/mol, respectively. 展开更多
关键词 Amagnesium KINETICS aluminothermic reduction MAGNESITE DOLOMITE
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Genetic differentiations between randomly and selectively bred pig populations in Yunnan,China 被引量:10
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作者 亐开兴 吴桂生 +4 位作者 苟潇 严达伟 连林生 Mumtaz Baig 张亚平 《Zoological Research》 CAS CSCD 北大核心 2011年第3期255-261,共7页
To assess the genetic diversity between randomly and selectively bred populations,we sequenced 438 bp of the mitochondrial DNA control region from 102 pigs.These samples represented four native pig breeds,one nucleus ... To assess the genetic diversity between randomly and selectively bred populations,we sequenced 438 bp of the mitochondrial DNA control region from 102 pigs.These samples represented four native pig breeds,one nucleus and one conservation herd from Yunnan,China.Twenty haplotypes with sixteen polymorphic sites were identified.The number of haplotypes in the nucleus herd of Saba pig and the conservation herd of Banna miniature pig were restricted to three and one,respectively,while the randomly bred pig populations exhibited over six haplotypes.Notably,haplotype diversity in randomly bred populations was significantly greater than the selectively bred populations(h=0.732 vs.0.425 and 0,exact test,P≤0.0036).These findings demonstrate that selective breeding generated low genetic diversity compared to randomly bred pig breeds.A timely intervention and well programmed breeding approach would stop further genetic diversity reduction in the nucleus and conservation herds of native pig breeds.Otherwise,selective breeding would dramatically reduce genetic diversity in only several years,indicating that sharp contradictions exist between breeding,conservation and genetic diversity.Genetic relationships are discussed based on net genetic distances among pig populations. 展开更多
关键词 Yunnan pig breeds Genetic diversity Randomly bred population Selectively bred population
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Mechanism of extracting magenesium from mixture of calcined magnesite and calcined dolomite by vacuum aluminothermic reduction 被引量:6
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作者 傅大学 王耀武 +3 位作者 彭建平 狄跃忠 陶绍虎 冯乃祥 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第8期2677-2686,共10页
The process of aluminothermic reduction of a mixture of calcined dolomite and calcined magnesite had been developed. The mechanism of the process was studied by SEM and EDS. The reduction process was divided into thre... The process of aluminothermic reduction of a mixture of calcined dolomite and calcined magnesite had been developed. The mechanism of the process was studied by SEM and EDS. The reduction process was divided into three stages:0≤ηt/ηf≤0.43±0.06, 0.43±0.06≤ηt/ηf≤0.9±0.02 and 0.9±0.02≤ηt/ηf<1, whereηt andηf are the reduction ratio at time t and the final reduction ratio obtained in the experiment at temperature T, respectively. The first stage included the direct reaction between calcined dolomite or calcined magnesite and Al with 12CaO·7Al2O3 and MgO·Al2O3 as products. The reaction rate depended on the chemical reaction. The CA phase was mainly produced in the second stage and the overall reaction rate was determined by both the diffusion of Ca2+ with molten Al and the chemical reaction. The CA2 phase was mainly produced in the third stage and the reaction process was controlled by the diffusion of Ca2+. 展开更多
关键词 magnesium aluminothermic reduction MAGNESITE DOLOMITE MECHANISM
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A Record of the Invasive Golden Apple Snail Pomacea canaliculata (Lamarck 1819) at Black Dragon Spring,Dianchi Basin 被引量:6
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作者 杜丽娜 Jonathan Davies +2 位作者 陈小勇 崔桂华 杨君兴 《Zoological Research》 CAS CSCD 北大核心 2007年第3期325-328,共4页
The golden apple snail Pomacea canaliculata (Lamarck 1819) was first recorded at Black Dragon Spring, Dianchi Basin, Baiyi Township, Songming County, Kunming City, Yunnan Province, China, in October 2004. The water ... The golden apple snail Pomacea canaliculata (Lamarck 1819) was first recorded at Black Dragon Spring, Dianchi Basin, Baiyi Township, Songming County, Kunming City, Yunnan Province, China, in October 2004. The water from the spring flows into the Songhuaba Reservoir, the major drinking water resource for Kunming City, and part of the Dianchi Lake basin. This is the first record of this invasive snail in the Dianchi Lake Basin. Pomacea canaliculata originates from Central and South America, and in Asia the snail has spread through deliberate and accidental introductions to the Philippines, Vietnam, Thailand, Laos, Cambodia, Malaysia, Indonesia, Papua New Guinea, Korea, Japan and South China. It has become a major pest in rice-growing areas, resulting in huge damage to crops. Strict prevention and control measures have to be implemented to prevent the spread of the snail in Yunnan, together with public awareness campaigns to inform the public of the dangers of this invasive snail. 展开更多
关键词 Golden apple snail Pomacea canaliculata Dianchi basin Kunming YUNNAN China
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Formation, distribution, and nature of Picea mongolica in China 被引量:5
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作者 邹春静 韩士杰 +1 位作者 徐文铎 苏宝玲 《Journal of Forestry Research》 SCIE CAS CSCD 2001年第3期187-191,210,共5页
Picea mongolica is an endemic and endangered species in China. Ecosystem made of Picea mongolica is a special sandy forest ecosystem in China. It is found at ecotone between forest and steppe, or agricultural district... Picea mongolica is an endemic and endangered species in China. Ecosystem made of Picea mongolica is a special sandy forest ecosystem in China. It is found at ecotone between forest and steppe, or agricultural district and pastoral area. Based on investigation, this paper discussed the formation and distribution of Picea mongolica and studied its nature according to ecotone theory. It is clarified that Picea mongolica belongs to Picea meyeri series. That is to say, it became a local race through long-term adaptation to the local climate, then formed allopatric semi-species, and finally turned into a taxonomical species. Picea mongolica forest is a super zonal climax community developing in ecotone between forest zone and steppe zone. 展开更多
关键词 Picea mongolica Formation Distribution NATURE Sandy forest ECOTONE
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The Chemical Constituents of Amoora yunnanensis 被引量:8
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作者 罗晓东 吴少华 +1 位作者 马云保 吴大刚 《Acta Botanica Sinica》 CSCD 2001年第4期426-430,共5页
Two new sterols, 3 beta, 7 alpha, 16 beta -trihydroxy-stigmast-5,22-diene (1), 3 beta, 7 alpha, 16 beta -trihydroxy-stigmast-5-ene (2), were isolated together with six known compounds, ergosta-5, 24(28)-dien-3 beta, 7... Two new sterols, 3 beta, 7 alpha, 16 beta -trihydroxy-stigmast-5,22-diene (1), 3 beta, 7 alpha, 16 beta -trihydroxy-stigmast-5-ene (2), were isolated together with six known compounds, ergosta-5, 24(28)-dien-3 beta, 7 alpha -diol (3), ergosta-5,24(28)-dien-3 beta, 7 beta, 16 beta -triol (4), beta -amyrone (5), beta -amyrin (6), 11 alpha, 12 alpha -epoxy-14-taraxeren-3-one (7), and 6-guaiene-4 alpha, 10 alpha -diol (8) from the EtOH extract of the bark of Amoora yunnanensis (H. L. Li) C. Y. Wu. Their structures were deduced on the basis of spectral data. 展开更多
关键词 Amoora yunnanensis meliaceae 3 beta 7 alpha 16 beta-trihydroxy-stigmast-5 22-diene 3 alpha 7 alpha 16 beta-trihydroxy-stigmast-5-ene
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Morphology of Pyrocoelia pygidialis Pic (Coleoptera:Lampyridae) with Notes on Its Biology 被引量:4
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作者 李学燕 解萌 +1 位作者 董平轩 梁醒财 《Entomotaxonomia》 CSCD 北大核心 2008年第4期300-308,共9页
Morphology of different development stages from egg, larva, pupa to adult (male and female) of the firefly, Pyrocoelia pygidialis Pic, was described in details. Some biological habits were noted according to the rec... Morphology of different development stages from egg, larva, pupa to adult (male and female) of the firefly, Pyrocoelia pygidialis Pic, was described in details. Some biological habits were noted according to the records of field collection and observation, with references to the rearing in the laboratory. With weakly luminous egg, larva, pupa and female adult, and much weaker luminous male adult only when disturbed, P pygidialis Pic is considered as a diurnal firefly, and chemical signal, instead of light signal, is possibly its dominant means of male-female recognition. 展开更多
关键词 COLEOPTERA LAMPYRIDAE Pyrocoelia MORPHOLOGY BIOLOGY YUNNAN
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Effect of Reducing Chemical Fertilizer on Rice Yield,Output Value,Content of Soil Carbon and Nitrogen after Utilizing the Milk Vetch 被引量:6
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作者 周兴 李再明 +5 位作者 谢坚 廖育林 杨曾平 鲁艳红 聂军 曹卫东 《Agricultural Science & Technology》 CAS 2015年第2期266-271,共6页
A located field experiment was carried out to study the effects of different amount of chemical fertilizer usage on rice yield,economic benefits of rice,soil carbon(C) and total nitrogen(TN) under ploughing back o... A located field experiment was carried out to study the effects of different amount of chemical fertilizer usage on rice yield,economic benefits of rice,soil carbon(C) and total nitrogen(TN) under ploughing back of Chinese milk vetch for 5consecutive years.Six treatments were included in the experiment,they are CK(unfertilized),CF(100% chemical fertilizer with the amount of N,P2O5,K2 O being150,75,120 kg/hm^2respectively),A1(22 500 kg/hm^2 Chinese milk vetch and 100%chemical fertilizer),A2(Chinese milk vetch and 80% nitrogen and potassium fertilizer and 100% phosphate fertilizer),A3(Chinese milk vetch and 60% nitrogen and potassium fertilizer and 100% phosphate fertilizer),A4(Chinese milk vetch and 40% nitrogen and potassium fertilizer and 100% phosphate fertilizer).The results were as follows:application of fertilizer could increase the yield of rice,while Chinese milk vetch combined with fertilizer application had a much more increase effect in rice yield.Under the condition of milk vetch application with 22 500 kg/hm^2,the early rice yield of the treatment A1 was significantly increased by 7.7% compared with that of CF.And the yield of treatment A3 was basically identical to or slight increase in comparison with that of CF.Decreasing amount of fertilizers cloud improve output value of rice in the case of the utilization of Chinese milk vetch.The treatment A1 increased output value of rice by 5.92% in comparison of CF,and treatment A2 was by 4.08% in the next.Treatment A4 showed much better effect in increasing soil organic carbon and total nitrogen in the paddy soil than those of treatments applying mineral fertilizer only.There was a significant reduction on soil organic carbon and TN in treatment A2 in comparison with that of CF.In general,amount of application of milk vetch with 22 500 kg/hm^2 could replace chemical fertilizer partially,it also could improve rice yield,decrease the production cost,and raise the utilization efficiency of nutrients. 展开更多
关键词 Chinese milk vetch Chemical fertilizer amounts RICE YIELD Economic benefits Content of soil C and total N
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