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Search Results: 1 - 10 of 332170 matches for " 王振友 "
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dirac算子自伴域的刻划
平心,
江苏科技大学学报(自然科学版) , 2006,
Abstract: ?dirac方程是量子力学的基本方程,讨论dirac算式的自伴域在数学物理中有很广泛的应用。本文利用辛几何的理论来描述dirac算式在区间[a,b]上的自伴域,得到dirac算子自伴域的完全刻划。
电磁挂钩通用检查仪的设计
The Design of the General Tester of the Electromagnetic Latch Hook
 [PDF]

付兴, 玉刚,, 恒新
Artificial Intelligence and Robotics Research (AIRR) , 2013, DOI: 10.12677/AIRR.2013.23017
Abstract:
电磁挂钩是军用飞机上实施投放的主要机构,其工作可靠性需要定期检测,但目前部队没有通用的检测设备,为提高部队快速反应能力,研制了电磁挂钩通用检查仪。仪器可对各种电磁挂钩进行精确、快速、方便测试。本文给出了该仪器的设计要求,并详细介绍了硬、软件设计及主要软件流程。该仪器经投入部队使用证明可以提供挂钩的可靠性和飞机的保证能力。
The electromagnetic latch hook is a main mechanism on the military aircraft to make delivery. Its working reliability should be tested regularly. But at present there is no general test equipment. In order to improve the quick reaction capability, a general tester of the electromagnetic latch hook is developed. The tester can make precise, rapid and convenient test. This paper gives the design requirements of the tester and elaborates the hardware and software design and the main software process. The application of the tester in the army has been proved that it can improve the reliability of the hatch hook and the support capability of the aircraft.
衡山自然保护区森林土壤中动物群落研究
,
地理学报 , 1989, DOI: 10.11821/xb198902009
Abstract: 作者通过一年的定位实验研究,初步阐明了衡山自然保护区森林土壤中动物群落的基本状况。共获得土壤动物30类,隶属于4门11纲,其中弹尾类、蝉螨类和线虫类为优势类群,占全部土壤动物捕获量的92.88%;平均土壤动物密度为67.27万个/m3;地带性常绿林下发育的黄棕壤中土壤动物密度高达100.47万个/m3,其次为针阔混交林和针叶林;土壤动物主要分布于森林凋落物层和土壤的腐殖质层中,向下急剧减少;在山地土壤垂直带上,土壤动物随海拔高度而变化。
对一类强非线性系统的分析
,
力学学报 , 1990, DOI: 10.6052/0459-1879-1990-3-1995-956
Abstract: 本文研究了一类强非线性系统,首先对系统在相平面上的全局结构进行定性分析,得到了系统参数的分叉值,然后研究了摄动方法在定性分析中的应用。
湘江流域工业污染源对农田生态系统土壤动物群落影响的研究
,
应用生态学报 , 1990,
Abstract: 对湘江流域工业污染区的土壤动物群落研究表明,接近污染源和污染物质富集的农田,土壤动物的种类和数量减少;工业污染区土壤的污染主要是重金属有毒物质的过量累积。调查共获得29类土壤动物,隶属于4门10纲,动物的种类与数量随着重金属污染程度的增加而递减,土壤动物密度与重金属元素hg、cd,zn、cu、as、pb的浓度密切相关,这在污染模拟实验中也得到证明。
稻田土壤动物群落初步调查
,
生态学杂志 , 1986,
Abstract: ?
schr?dinger算子第一特征值下界的估计
兰宁,
南京邮电大学学报(自然科学版) , 2007,
Abstract: 给出了带dirichlet边条件的schr?dinger算子问题-δf+wf=λff?ω≡0第一特征值λ1下界的估计,即λ1≥π2/d2,其中ω?rn为有界光滑凸区域,d为ω的直径,w:ω→r为非负函数。
有氧运动和锁阳多糖干预对糖尿病大鼠主动脉舒张功能的影响及其机制研究
The effect of aerobic exercise and Cynomorium Songaricum Polysaccharide intervention for dilatation function of aorta in diabetes rats and involved mechanisms

,
- , 2017, DOI: 1672-4291(2017)05-0117-08
Abstract: 探讨了有氧运动和锁阳多糖干预对糖尿病大鼠主动脉舒张功能的影响及其作用机制。实验分为4组:正常对照组,糖尿病组,糖尿病+有氧运动组和糖尿病+锁阳多糖组。8周后,测定血管功能,形态结构和内皮型一氧化氮合酶(endothelial nitricoxide synthase,eNOS),Akt激酶(Akt kinases, Akt)和肿瘤坏死生长因子(tumor necrosis growth factor α, TNF-α)的分布和表达。结果表明,糖尿病导致主动脉内皮结构损伤,降低Akt和eNOS表达,增加TNF-α表达,可能是导致主动脉舒张功能紊乱的重要因素;有氧运动和锁阳多糖干预可修复血管内皮结构,增加Akt和eNOS表达,降低TNF-α表达,可能是改善主动脉舒张功能的重要机制
基于人工表面等离激元的多波束切换天线
Multi-beam switching antenna based on spoof surface plasmon polaritons

,,肖顺
- , 2018,
Abstract: 文中提出了一种基于人工表面等离激元的多波束切换天线。该多波束切换天线由6个相同的端射天线围绕同一圆心旋转排列组成,相邻端射天线之间的夹角为60°,端射天线到圆心的距离均为70 mm。每个端射天线由馈源单极子、反射器和能产生人工表面等离激元的开口谐振环结构组成,实现了全向场到定向场的转换及辐射。仿真与测试结果表明,所设计天线在9~10.8 GHz频段内可以实现波束切换的功能,且具有高增益的特性,平均峰值增益约为19.3 dBi。
Based on spoof surface plasmon polaritons, a multi-beam switching antenna is proposed, including 6 identical end-fire antennas rotating around the center of the circle. The angle between the near end antennas is 60° and the distance from the end fire antenna to the center of the circle is 70 mm. Each end-fire antenna consists of a monopole, a reflector and split-ring resonators that can generate spoof surface plasmon polaritons, completing the conversion from the omnidirectional field to directional field and the radiation. Simulation and measurement results show that the proposed antenna can achieve the function of beam switching in frequency bands of 9—10.8 GHz. The antenna has the characteristic of high gain and the average peak gain is about 19.3 dBi
凤丹浸提液对玉米幼苗生长和根际土壤性质的影响
Effects of aqueous extracts from Paeonia ostii on growth of Zea mays seedlings and properties of rhizospheric soil

兴飞,,,
- , 2015,
Abstract: 【目的】探讨凤丹浸提液对玉米幼苗生长和根际土壤性质的影响,为确定凤丹与作物之间的轮作模式提供参考。【方法】用凤丹根、茎、叶浸提液及其根际土浸提液浇灌盆栽玉米幼苗,研究凤丹浸提液对玉米幼苗生长、根际土壤酶活性、土壤养分和微生物数量的影响。【结果】凤丹浸提液对玉米幼苗的生长具有抑制作用,与对照组相比,凤丹浸提液浇灌玉米幼苗的株高、根长变短,植株的鲜质量和干质量减少。凤丹浸提液降低了土壤酶活性,减少了土壤养分含量及细菌、放线菌和真菌的数量,与对照组相比,凤丹根浸提液处理组的减少程度最大,其次是凤丹根际土浸提液,凤丹茎和叶浸提液的影响较小。相关性分析发现,除过氧化氢酶外,土壤酶活性与微生物数量呈显著正相关,土壤有机质含量对土壤酶活性和微生物数量的影响大于其对全氮、全磷和全钾的影响。【结论】凤丹不同部位浸提液对玉米幼苗生长、土壤酶活性、微生物数量和土壤养分的抑制作用大小表现为凤丹根浸提液>凤丹根际土浸提液>凤丹茎、叶浸提液。
【Objective】This study focused on the effects of aqueous extracts from Paeonia ostii on growth of Zea mays seedlings and properties of rhizospheric soil to provide reference for rotation mode between P.ostii and crop.【Method】Pot experiment was conducted to investigated the effects of different aqueous extracts from P.ostii on Z.mays seedlings growth,soil enzyme activities,soil nutrients and microbial quantities.【Result】Aqueous extracts from P.ostii inhibited Z.mays seedlings growth.Compared with the control group,the lengths of aboveground parts and roots were shorter and fresh weight and dry weight of seedlings were decreased.The activities of soil enzymes,content of soil nutrients,and amounts of bacteria,actinomyces and fungi were also decreased.Compared with the control group,the inhibiting effect of aqueous extract from root of P.ostii was greater than others.Correlation analysis found that soil enzyme activities had a significant positive correlation with microbial quantities except catalase.The effects of soil organic matter content on soil enzyme activities and microbial quantities were greater than that of total N,P and K.【Conclusion】The inhibitions on soil enzyme activities,microbial quantities and soil nutrients were in the decreasing order of aqueous extract from root of P.ostii>aqueous extract from rhizospheric soil of P.ostii>aqueous extract from stem and leaf of P.ostii.
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