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Search Results: 1 - 10 of 322858 matches for " 侯大为<br>WANG Qian "
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Research Progress in Pathogenesis of Oral Squamous Cell Carcinoma

王倩, 大为<br>WANG Qian, HOU Da-wei
- , 2018, DOI: 10.13701/j.cnki.kqyxyj.2018.11.005
Abstract: 摘要 口腔鳞状细胞癌(oral squamous cell carcinoma,OSCC)的形成是多种因素作用导致基因突变的结果。淋巴结局部转移是OSCC的最主要也是对治疗预后影响最大的生物学行为之一。OSCC发生发展的原因及其淋巴转移的生物学机制尚未明确。探求OSCC发生和转移过程中的生物学机制对明确OSCC的发病机制和寻找潜在的治疗靶点有重要意义。本文从不同角度对OSCC发病及转移机制进行综述
Metallogenesis of the Indo-Asian Collisional Orogen: New Advances

HOU Zeng-qian,WANG Er-qi,<br>增谦,王二七
地球学报 , 2008,
Abstract: "印度-亚洲大陆主碰撞带成矿作用"973项目(2002~2008年)以青藏高原为研究对象,以构建大陆碰撞成矿理论体系为总体科学目标,经过70多位科技人员历经5年研究,取得了重大研究成果.笔者初步总结了项目在成矿动力学背景、壳/幔深部过程、大陆成矿作用及战略新区预测等方面的研究进展.项目详细再塑了青藏高原碰撞造山过程,创新性提出了碰撞造山二阶段演化模式,即主碰撞聚合(65~41 Ma)、晚碰撞转换(40~26 Ma)、后碰撞伸展(25~0 Ma)二阶段连续演变历程,发现主碰撞期发牛岩浆大规模底侵与地壳垂向增生,晚碰撞期出现地幔物质测向流动与幔源钾质岩浆组合,后碰撞期出现岩石圈减薄与伸展岩浆组合.伴随碰撞过程,应力场出现自挤压(压扭)到伸展(张扭)交替更迭变化.综合研究提出了青藏高原碰撞造山地球动力学模式.创新性地提出了大陆碰撞成矿理论体系新框架,包括三大碰撞成矿作用(主碰撞汇聚成矿作用、晚碰撞转换成矿作用和后碰撞伸展成矿作用)、10种重要的成矿系统和12种大陆特色的矿床类型,揭示了大陆碰撞带的区域成矿规律.初步提出了以大陆型斑岩铜矿新理论为代表的5类矿床成矿新模型,揭示了大陆碰撞带金属成矿机制.在系列地质、矿产综合编图和数据库建没基础上,提出了成矿预测新思路和新方法,提交了7处找矿战略新区,并在若干靶区取得找矿突破,探索出一条科研带动勘查突破、勘查提升理论认识的新路.
Sediment quality guidelines and potential ecological risk assessment for heavy metals based on equilibrium partitioning approach in Taihu Lake

HOU Jun,WANG Chao,WANG Peifang,QIAN Jin,<br>,王超,王沛芳,钱进
环境科学学报 , 2012,
Abstract: The development of sediment quality guidelines (SQGs) is one of the challenges for protection of aquatic biodiversity. We applied Equilibrium Partitioning Approach to preliminarily derive the sediment quality guidelines for heavy metals such as lead, copper, zinc and chromium in different regions of Taihu Lake, and analyzed the contributions of the normalization factors to SQGs. Potential ecological risk assessment of the heavy metals in sediments based on SQG-Q method was also conducted. The calculated SQGs of lead, copper, zinc and chromium in different regions of Taihu Lake were, respectively, 21.2~307.4 mg·kg-1, 52.3~281.0 mg·kg-1, 399.7~1659.1 mg·kg-1 and 21.2~68.7 mg·kg-1. For SQGPb, the AVS was the most important normalization factor, for SQGCu and SQGZn, the Kp·WQC and fine material were the most important, while SQGCr was determined by Kp·WQC, fine material and residual. Comparing to the calculated SQGs, the exceeding extent of heavy metals followed an order of Cr>Pb>Zn>Cu. This suggested that there existed "moderate level" ecological risks for heavy metals in the sediments of Taihu Lake, and the potential ecological risks decreased in the order of Zhushan Bay>Meiliang Bay>Gonghu Bay>Eastern Taihu Lake>Eastern Coastal Area, Western Coastal Area>Middle Area>Southern Coastal Area.
Mesozoic Ultra-metamorphism and Mantle Plume in North China Platform

LI Hong-yang,HOU Zeng-qian,WANG Guo-fu,<br>李红阳,增谦,王国富
地球学报 , 1996,
Abstract: Based on the discussions of the Mesozoic gold mineralization, granites and alkaline rocks in the "Archaean "high grade metamorphic terrains of gold enriched aera, such as northwest Hebei, Jiaodong East Shandong, the paper proposes the Mesozoic ultra-metamorphism which includes migmatization, granitization and rheologic gneiss. It is considered to be one of the important causes of the anomalous geological phenomena of north China platform which are the deeper metamorphism of the "Archaean" high grade metamorphic terrains, the same geological body having different isotopic ages, intensive magmatic activity in Mesozoic Era. It is not only an important deep geological process of North China platform activation but also the concret embodiment of deep" de-rooting". Mesozoic mantle plume is the deep mechanism of the ultra-metamorphism, metamorphic core complexes, gold mineralization. It is basic reasons for the north China platform activation in Mesozoic Era.
Accumulation and health risk assessment of heavy metals in kindergarten surface dust in the city of Kaifeng

WANG Xiaoyun,MA Jianhu,HOU Qian,DUAN Haijing,<br>王晓云,马建华,,段海静
环境科学学报 , 2011,
Abstract: Samples of surface dust were collected from thirty-one kindergartens in Kaifeng. The concentrations of Pb, Zn, Cr, Cu and Ni in different size-fractionated (<0.15, 0.15~0.25 and >0.25 mm in diameter) samples and in the mixed samples with all size fractions were determined by flame atomic absorption spectrophotometry (F-AAS). The accumulations of heavy metals in dust were analyzed using Enrichment Factor (EF), and health risks of heavy metals to young children were assessed using Health Index (HI). The results show that the average concentrations of Pb, Zn, Ni, Cu and Cr in the samples are 242.99, 297.32, 52.57, 38.92 and 82.13 mg·kg-1 respectively, which all exceed the background values in the fluvo-aquic soils of China. The metals Pb, Zn and Cr, mainly from human activities and enriched in dust significantly, are anthropogenic source metals; Ni, mainly from natural factors, is a natural source metals, while Cu, both from human activities and natural factors, is a mixed source metals. The samples from the old downtown area, industrial area and near major roads are polluted with heavy metals much more heavily than those in other areas of the city. It was also found that Pb is mainly enriched in the coarse fraction (>0.25 mm) of dust, Zn in the fine fraction (<0.15 mm), and Cu, Cr and Ni in all size fractions of dust without significant differences. The particle compositions of dust are fine 55%, coarse 28% and medium 17%, while the average mass percents of all heavy metals in the different size fractions are 50.03% in fine dust, 29.55% in coarse and 18.43% in medium. The main exposure pathway of heavy metals to young children is hand-to-mouth ingestion. The HIs indicate that heavy metals have different levels of health risk to young children (Pb>Cr>Ni>Zn>Cu), in eight (25.8%) kindergartens HIPb>1, and one (3.2%) HICr>1. A health risk from Pb and Cr exists in some kindergartens; but generally, there is no health risk of heavy metals associated with surface dust in most kindergartens in Kaifeng.
Design of nonlinear integrated controller for single-machine-infinite-bus system with static-synchronous-series-compensator

WANG Ben,QIAN Bi-fu,XU Wang-liang,HOU Rong-jun,<br>王奔,钱碧甫,徐万良,荣均
控制理论与应用 , 2012,
Abstract: For the interactions between the single-machine-infinite-bus system with static-synchronous-seriescompensator, the excitation and the stream valve control, we develop a 4th order nonlinear model with three inputs and three outputs. This model is decoupled and linearized by using the dynamic inverse system theory to obtain three SISO pseudo linear systems; with them we design three SISO controllers by using the variable structure control theory. Simulation results on MATLAB show the feasibility and effectiveness of this control strategy in stabilizing the power-angle, the generator terminal voltage and the transmission power.

Wang Zhengrong,Zhang Boheng,Liu Shulong,Yan Qian,<br>陈国夫,赵尚弘,王屹山,王贤华,
光子学报 , 1996,
Abstract: 不加腔外展宽器的高重复率钛宝石再生放大器陈国夫,赵尚弘,王屹山,王贤华,侯洵(中国科学院西安光机所瞬态光学技术国家重点实验室,西安710068)最近我们在省略腔外展宽器的放大器中实现了自锁模钛宝石脉冲的放大,实验中我们用自制的的振荡器产生脉宽为20f...
New analytical potential energy function for doubly charged diatomic molecules

Wang Fan-Hou,Yang Chuan-Lu,Zhu Zheng-He,Jing Fu-Qian,<br>王藩,杨传路,朱正和,经福谦
中国物理 B , 2005,
Abstract: 提出了能更好反映双荷电双原子分子势能曲线特点的新解析势能函数,并推导出了相应的二、三、四阶力常数计算公式;作为新函数的应用实例,给出了BH2+, He22+ 和HF2+等分子离子的解析势能函数,力常数和光谱数据。
Bioavailability and Potential Ecological Risk of Soil Heavy Metals in Kindergartens,Kaifeng City

HOU Qian,MA Jian-hu,WANG Xiao-yun,DUAN Hai-jing,<br>,马建华,王晓云,段海静
环境科学 , 2011,
Abstract: 在开封市城区27个幼儿园采集土壤表层样品,采用Tessier法提取并用F-AAS法测定不同化学形态的Pb、Zn、Ni、Cu和Cr含量,在计算重金属迁移系数(MF)和生态风险指数(RI)的基础上,对重金属化学形态分布、迁移能力、生物活性和潜在生态风险进行了研究.结果表明,城区幼儿园土壤Zn、Cu、Cr、Pb和Ni的平均含量分别为138.13、 24.08、 132.03、 130.38和42.44 mg·kg-1,分别是对照土壤的2.83、 2.27、 1.45、 1.33和0.98倍.不同样点处重金属形态分布有明显差异.除土壤Zn以铁锰氧化物结合态为主外,其他重金属均以残渣态为主;大多数样点重金属可交换态含量最低.土壤Pb的迁移能力和生物活性最强,其平均MF为24.9%,其次是Ni(18.4%)和Zn(16.4%);Cr(1.0%)和Cu(4.8%)则很稳定.大部分幼儿园土壤处于重金属中等污染和中等生态风险状态.Pb对总体污染和综合风险的贡献率分别为56.0%和69.5%,是最主要的污染和风险因子.土壤重金属生态风险与其生物活性相一致,综合生态风险与总体污染程度呈显著正相关.在应用Hkanson法进行污染物潜在生态风险评价时,必须根据所研究的污染物种类和数量对评价标准进行调整.
RiMOM2:A Customizable Framework of Ontology Matching

LI Hu,ZHANG Xiao,ZHONG Qian,HOU Lei,WANG Zhi-chun,<br>李虎,张啸,仲茜,,王志春
计算机科学 , 2011,
Abstract: As the representation of the semantic Web, the ontology is the key element of the semantic Web system, and the key for knowledge sharing and working together. However, in the real world, the inherent heterogeneous and distribution of ontology have greatly limited the knowledge sharing and data integration. In order to realize the knowledge sharing and data integration, the ontology matching has been widely studied. With the deepening of the research, numerows of effective ontology matching methods have been proposed. RiMOM2 is a multi-strategy framework of ontology matching, which integrated many effective ontology matching methods. For primary users, RiMOM2 hides unnecessary thresholds and parameters settings in order to achieve an easily manipulated ontology matching with common rectuiremenu. While for advanced users, it provides a customizable matching process function so that it can be used for ontology matching with specific requirements. hhe matching method components also arc easily extensible in the framework.
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