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条形荷载下H-V加筋砂土地基模型试验研究 被引量:15
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作者 张孟喜 赵飞 侯娟 《土木工程学报》 EI CSCD 北大核心 2008年第2期94-99,共6页
提出了一种新的H-V立体加筋(horizontal-vertical)模式,这是一种在传统水平条带式筋条上布置竖向或空间筋材形成的组合立体形式,其显著特点是所加竖向筋材能有效地限制筋材间土体的侧向位移,在竖筋侧面产生侧阻力,而且在竖筋间将形成&qu... 提出了一种新的H-V立体加筋(horizontal-vertical)模式,这是一种在传统水平条带式筋条上布置竖向或空间筋材形成的组合立体形式,其显著特点是所加竖向筋材能有效地限制筋材间土体的侧向位移,在竖筋侧面产生侧阻力,而且在竖筋间将形成"土体加强区",从而有效改变加筋土的受力状况,提高土体的强度和稳定性。本文分别对水平加筋和H-V加筋两种加筋方式进行了多组的加筋地基模型试验,并将这两种加筋方式对承载力和沉降的影响进行了对比分析。试验结果表明,H-V加筋方式能明显提高地基承载力和减小地基沉降,而且其加筋效果随着竖筋高度和水平方向筋材长度的增加不断提高。在模型试验的基础上,初步分析了H-V加筋方式的作用机理。 展开更多
关键词 h-v加筋 地基 模型试验 承载力 沉降
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H-V加筋黏性土的强度与变形特性 被引量:16
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作者 张孟喜 张贤波 段晶晶 《岩土力学》 EI CAS CSCD 北大核心 2009年第6期1563-1568,共6页
在提出非满布的H-V(水平-竖向)加筋的基础上,设计了非满布多层H-V加筋黏土的试验方案,以镀锌铁皮和有机玻璃为加筋材料进行了44组固结不排水三轴剪切试验。通过不同竖筋布置的加筋黏土三轴试验研究了加筋黏性土的应力-应变关系、强度特... 在提出非满布的H-V(水平-竖向)加筋的基础上,设计了非满布多层H-V加筋黏土的试验方案,以镀锌铁皮和有机玻璃为加筋材料进行了44组固结不排水三轴剪切试验。通过不同竖筋布置的加筋黏土三轴试验研究了加筋黏性土的应力-应变关系、强度特性及破坏形态,探讨了不同加筋高度、不同围压及不同筋材对加筋黏土强度的影响。试验结果表明:相对于无筋土及传统的水平加筋土而言,其峰值偏应力和抗剪强度均有大幅度提高。 展开更多
关键词 h-v(水平-竖向)加筋 黏土 三轴试验 强度 变形
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H-V加筋饱和砂土性状的三轴试验研究 被引量:11
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作者 张孟喜 陈高峰 +1 位作者 朱引 李晋杰 《岩土力学》 EI CAS CSCD 北大核心 2010年第5期1345-1351,共7页
进行了H-V(水平-竖向)加筋饱和砂土固结不排水三轴试验。加筋材料采用镀锌铁皮和有机玻璃两种不同材料,在不同竖筋高度、不同围压下共进行了44组试验,研究了加筋饱和砂土的应力-应变关系、孔压-应变关系、强度特性及破坏形态,探讨了不... 进行了H-V(水平-竖向)加筋饱和砂土固结不排水三轴试验。加筋材料采用镀锌铁皮和有机玻璃两种不同材料,在不同竖筋高度、不同围压下共进行了44组试验,研究了加筋饱和砂土的应力-应变关系、孔压-应变关系、强度特性及破坏形态,探讨了不同加筋高度、不同围压及不同筋材对加筋饱和砂土强度的影响,同时比较了立体加筋与土工格室加筋的异同,对饱和紧砂的空化现象及其影响进行了分析。试验结果表明,相对于无筋土及传统的水平加筋土而言,其抗剪强度均有大幅度提高;尤其是镀锌铁皮加筋,不仅提高了饱和砂土的有效黏聚力,也提高了有效内摩擦角,同时改善了砂土的延性。 展开更多
关键词 h-v(水平-竖向)加筋 饱和砂土 三轴试验 强度 变形 空化
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H-V加筋土性状的颗粒流细观模拟 被引量:20
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作者 张孟喜 张石磊 《岩土工程学报》 EI CAS CSCD 北大核心 2008年第5期625-631,共7页
正交水平-竖向(H-V)加筋是一种新型的土工加筋技术,在H-V加筋土中除了有传统的水平筋条外,还在水平筋条上设置了竖向齿筋。结合已完成的加筋土三轴试验,采用基于离散元理论的颗粒流软件(PFC2D)对试验进行了仿真模拟,较好地拟合了H-V加... 正交水平-竖向(H-V)加筋是一种新型的土工加筋技术,在H-V加筋土中除了有传统的水平筋条外,还在水平筋条上设置了竖向齿筋。结合已完成的加筋土三轴试验,采用基于离散元理论的颗粒流软件(PFC2D)对试验进行了仿真模拟,较好地拟合了H-V加筋砂土三轴试验的应力–应变曲线,并通过观测颗粒的受力情况分析了H-V加筋砂土的受力机理。通过引入颗粒流理论,对H-V加筋砂土试样的剪切带形成进行了细观数值模拟,揭示了H-V加筋土中剪切带产生、扩展的渐进破坏规律。 展开更多
关键词 h-v加筋 三轴试验 颗粒流 离散元 剪切带
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基于有限元强度折减法的H-V加筋地基破坏机理 被引量:9
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作者 张陶陶 张孟喜 侯娟 《上海交通大学学报》 EI CAS CSCD 北大核心 2011年第5期757-761,共5页
基于边坡稳定性分析中的有限元强度折减法,利用ABAQUS软件对纯砂地基、水平加筋地基和水平与竖向(H-V)加筋地基进行多组数值模拟.采用安全系数分析H-V加筋地基对地基承载力的影响,通过ABAQUS软件后处理功能观察地基在强度折减系数增大... 基于边坡稳定性分析中的有限元强度折减法,利用ABAQUS软件对纯砂地基、水平加筋地基和水平与竖向(H-V)加筋地基进行多组数值模拟.采用安全系数分析H-V加筋地基对地基承载力的影响,通过ABAQUS软件后处理功能观察地基在强度折减系数增大过程中塑性区的扩展情况及最后破坏时的破坏面,并对不同加筋地基的破坏模式进行分析.结果表明:H-V加筋能使地基承载力得到大幅提高;地基的破坏模式因加筋体的存在而发生一定程度的改变;在同等试验条件下,H-V加筋效果高于水平加筋,单层H-V加筋地基的加筋效果随加筋深度的增加而减弱. 展开更多
关键词 有限元强度折减法 h-v加筋 承载力 折减系数 加筋深度
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经口咽齿突切除结合H-V环复位治疗重度陈旧性寰枢椎脱位 被引量:3
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作者 张志刚 赵刚 +6 位作者 石伟 李海 刘绍臣 林延军 吴其常 卞传华 宋德功 《中国矫形外科杂志》 CAS CSCD 2001年第12期1179-1181,共3页
目的 :探讨经口咽齿突切除结合H V环复位治疗重度陈旧性寰枢椎脱位的方法及重度寰枢椎脱位的病理机制。方法 :对 2例重度陈旧性寰枢椎脱位患者采用经口咽齿突切除前方松解、减压 ,结合H V环缓慢复位 ,二期行后路减压枕颈融合方法治疗。... 目的 :探讨经口咽齿突切除结合H V环复位治疗重度陈旧性寰枢椎脱位的方法及重度寰枢椎脱位的病理机制。方法 :对 2例重度陈旧性寰枢椎脱位患者采用经口咽齿突切除前方松解、减压 ,结合H V环缓慢复位 ,二期行后路减压枕颈融合方法治疗。结果 :1例术前FrankelC级恢复至正常 ,1例术前FrankelC级恢复至D级。结论 :重度陈旧性寰枢椎脱位 ,在寰椎前弓与枢椎体间形成纤维组织增生 ,这种纤维连接使寰枢椎相对趋向稳定是障碍复位的主要因素。结合H V环缓慢牵引 ,复位制动 ,经口咽入路行齿突切除前方松解减压 ,二期行后路减压枕颈融合 ,确能从前后方解除致压因素 ,结合H V环制动、复位能够保障复位和手术过程中头颈部的运动在H V环控制下 。 展开更多
关键词 寰枢椎脱位 经口咽入路 h-v 枕颈融合术
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H-V立体加筋黏土单轴试验 被引量:1
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作者 高俊丽 曹威 +1 位作者 徐宏飞 袁川 《地下空间与工程学报》 CSCD 北大核心 2019年第4期1024-1031,共8页
为了研究H-V立体加筋黏土应力应变曲线及强度特性,在恒定应变加载速率下,对H-V立体加筋黏土进行了单轴无侧限抗压强度试验,得到了不同加筋高度及不同含水率下的应力应变曲线。在给定的含水率下,研究了加筋高度为5 mm、10 mm、15 mm、20... 为了研究H-V立体加筋黏土应力应变曲线及强度特性,在恒定应变加载速率下,对H-V立体加筋黏土进行了单轴无侧限抗压强度试验,得到了不同加筋高度及不同含水率下的应力应变曲线。在给定的含水率下,研究了加筋高度为5 mm、10 mm、15 mm、20 mm的HV立体加筋黏性土与极限应力的关系,得出了在一定范围内极限应力随竖向加筋率的增大而增大,但是其中存在一个最佳竖向加筋率,大于或小于这个加筋率,试样都不能达到最佳效果。在给定的加筋高度下,研究极限应力与含水率之间的关系,得出了极限应力随含水率的增加,先增大后减小的规律。此外,本文还研究了极限应力与分维数D之间的关系,得出了极限应力随着分形维数D的增加,先增加后减小,存在一个最优值。 展开更多
关键词 h-v立体加筋 黏土 单轴试验 含水率 分维数
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一种用于大气超光谱探测的异型双H-V消偏器 被引量:5
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作者 唐茜 郭立新 赵葆常 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2017年第12期3913-3919,共7页
高精度的大气探测光谱仪应用十分广泛,但是由于太阳发出的自然光与大气作用后所产生的(部分)偏振光会影响设备的探测精度,所以该类光谱仪通常需要去除入射光的偏振影响。论文针对大气超光谱成像探测设备的消偏需求,提出了一种新型的双H-... 高精度的大气探测光谱仪应用十分广泛,但是由于太阳发出的自然光与大气作用后所产生的(部分)偏振光会影响设备的探测精度,所以该类光谱仪通常需要去除入射光的偏振影响。论文针对大气超光谱成像探测设备的消偏需求,提出了一种新型的双H-V(horizontal-vertical)消偏器。由于晶体的双折射结构在光学原理上可以产生消偏效应,所以消偏器材料通常为双折射晶体,但是该结构同时又会产生双像,从而降低光谱仪的成像质量。针对此问题,结合该大气超光谱探测设备中空间维像元合并的特点提出了一种异型双H-V消偏器。它不同于传统双H-V消偏器中两子H-V楔角相等的结构,所提出的异型双H-V消偏器两个子H-V楔角不同,从而使其在光谱维及空间维对应不同的双像距,在满足退偏度要求的同时保证了成像质量,很好的解决了高消偏度与高成像质量之间的矛盾。论文详细阐述了消偏器的设计方案,并针对消偏效果与成像质量进行了分析,消偏器的退偏率优于98.8%,并且在空间方向双像所占像元数仅为合并像元的8.7%。 展开更多
关键词 光谱仪 偏振灵敏度 h-v消偏器 楔角
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直升机H-V包线拓展飞行试验方法研究 被引量:3
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作者 王勇 孙光 陈永禄 《西安航空学院学报》 2016年第3期21-24,共4页
直升机H-V包线是直升机在发动机失效后安全着陆或成功复飞的基础条件。指出了影响H-V包线范围的主要因素是重量相对密度比(W/σ),提出了直升机H-V包线拓展试飞方法,针对某型机进行了H-V包线下边界拓展和上边界拓展飞行试验,分析飞行试... 直升机H-V包线是直升机在发动机失效后安全着陆或成功复飞的基础条件。指出了影响H-V包线范围的主要因素是重量相对密度比(W/σ),提出了直升机H-V包线拓展试飞方法,针对某型机进行了H-V包线下边界拓展和上边界拓展飞行试验,分析飞行试验结果,给出了H-V包线图,并明确了H-V包线拓展飞行关键技术和注意事项,有助于其他直升机H-V包线拓展飞行试验的顺利开展。 展开更多
关键词 h-v包线 飞行试验 边界拓展
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Selective extraction of titanium from Ti-bearing slag via the enhanced depolarization effect of liquid copper cathode 被引量:8
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作者 Zhenghao Pu Handong Jiao +2 位作者 Zhishan Mi Mingyong Wang Shuqiang Jiao 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2020年第3期43-48,共6页
Ti-bearing slag(TiO2>20 wt%)is a valuable titanium secondary resource.The extraction of titanium from the slag is difficult due to the complex composition and structure.Although molten oxide electrolysis is conside... Ti-bearing slag(TiO2>20 wt%)is a valuable titanium secondary resource.The extraction of titanium from the slag is difficult due to the complex composition and structure.Although molten oxide electrolysis is considered as a promising method,silicon will be preferentially electroreduced compared to titanium due to low theoretical decomposition voltage.In this work,a liquid copper cathode is used to selectively extract titanium from molten Al2O3-MgO-CaO-TiO2-SiO2 electrolyte.It is found that comparing to silicon,titanium can be preferentially reduced by one-step electron transfer due to the enhanced depolarization effect on a liquid copper cathode.So,Ti-Cu alloys are firstly obtained from molten Ti-bearing slag,and then Ti-Si alloys are co-electrodeposited in the molten oxide electrolyte with low TiO2 content.It may be ascribed to the larger binding force between titanium and copper than that between silicon and copper.It provides an effective strategy for the separation of titanium from of Ti-bearing slag. 展开更多
关键词 TITANIUM alloys MOLTEN OXIDES ELECTROLYSIS Liquid CATHODE Selective depolarIZATION
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Accurate Measurement of Raman Depolarization Ratio in Gaseous CO2
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作者 靳玉娟 喻远琴 +3 位作者 王钰熙 林珂 周晓国 刘世林 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2015年第1期17-20,I0001,共5页
The Raman depolarization ratios of gaseous CO2 in the spectral range of 1240-1430 cm-I are determined with a sensitive photoacoustic Raman spectroscopy, and more accurate data compared to the literature results are pr... The Raman depolarization ratios of gaseous CO2 in the spectral range of 1240-1430 cm-I are determined with a sensitive photoacoustic Raman spectroscopy, and more accurate data compared to the literature results are presented. The precision of the obtained depolarization ratio is achieved by measuring and fitting the dependence of the PARS signal intensity on the cross angle between the polarizations of two incident laser beams. 展开更多
关键词 depolarization ratio Accurate measurement Photoacoustic Raman spec-troscopy Global fitting
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Orientation-dependent depolarization of supercontinuum in BaF2 crystal 被引量:1
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作者 Zi-Xi Li Cheng Gong +3 位作者 Tian-Jiao Shao Lin-Qiang Hua Xue-Bin Bian Xiao-Jun Liu 《Chinese Physics B》 SCIE EI CAS CSCD 2020年第1期324-328,共5页
We present a systematic investigation of the depolarization properties of a supercontinuum accompanied with femtosecond laser filamentation in barium fluoride(BaF2)crystal.It is found that the depolarization of the su... We present a systematic investigation of the depolarization properties of a supercontinuum accompanied with femtosecond laser filamentation in barium fluoride(BaF2)crystal.It is found that the depolarization of the supercontinuum depends strongly on the crystal orientations with respect to the incident laser polarization.At most crystal orientations,the depolarization of the supercontinuum rises with the increase of the input laser energies and finally saturates.While at 45°,the depolarization of the supercontinuum is not changed and keeps nearly negligible with the increase of the input laser energies.These peculiar depolarization properties of the supercontinuum can be ascribed to the orientation dependence of the cross-polarized wave(XPW)generation and ionization-induced plasma scattering in the BaF2 crystal. 展开更多
关键词 femtosecond laser filamentation SUPERCONTINUUM depolarIZATION
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mTORC1 induces plasma membrane depolarization and promotes preosteoblast senescence by regulating the sodium channel Scn1a 被引量:2
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作者 Ajuan Chen Jian Jin +12 位作者 Shasha Cheng Zezheng Liu Cheng Yang Qingjing Chen Wenquan Liang Kai Li Dawei Kang Zhicong Ouyang Chenfeng Yao Xiaochun Bai Qingchu Li Dadi Jin Bin Huang 《Bone Research》 SCIE CAS CSCD 2022年第2期394-408,共15页
Senescence impairs preosteoblast expansion and differentiation into functional osteoblasts,blunts their responses to bone formation-stimulating factors and stimulates their secretion of osteoclast-activating factors.D... Senescence impairs preosteoblast expansion and differentiation into functional osteoblasts,blunts their responses to bone formation-stimulating factors and stimulates their secretion of osteoclast-activating factors.Due to these adverse effects,preosteoblast senescence is a crucial target for the treatment of age-related bone loss;however,the underlying mechanism remains unclear.We found that mTORC1 accelerated preosteoblast senescence in vitro and in a mouse model.Mechanistically,mTORC1 induced a change in the membrane potential from polarization to depolarization,thus promoting cell senescence by increasing Ca^(2+)influx and activating downstream NFAT/ATF3/p53 signaling.We further identified the sodium channel Scn1a as a mediator of membrane depolarization in senescent preosteoblasts.Scn1a expression was found to be positively regulated by mTORC1 upstream of C/EBPα,whereas its permeability to Na^(+)was found to be gated by protein kinase A(PKA)-induced phosphorylation.Prosenescent stresses increased the permeability of Scn1a to Na^(+)by suppressing PKA activity and induced depolarization in preosteoblasts.Together,our findings identify a novel pathway involving mTORC1,Scn1a expression and gating,plasma membrane depolarization,increased Ca^(2+)influx and NFAT/ATF3/p53 signaling in the regulation of preosteoblast senescence.Pharmaceutical studies of the related pathways and agents might lead to novel potential treatments for agerelated bone loss. 展开更多
关键词 depolarIZATION mTORC1 treatment
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Impact of Depolarization Phenomena on Polarized MIMO Channel Performances 被引量:2
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作者 Nuttapol PRAYONGPUN Kosai RAOOF 《International Journal of Communications, Network and System Sciences》 2008年第2期124-129,共6页
The performance and capacity of multiple-input multiple-output (MIMO) wireless channels are limited by the spatial fading correlation between antenna elements. This limitation is due to the use of mono polarized anten... The performance and capacity of multiple-input multiple-output (MIMO) wireless channels are limited by the spatial fading correlation between antenna elements. This limitation is due to the use of mono polarized antennas at receiver and transmitter sides. In this paper, in order to reduce the antenna correlation, the polarization diversity technique is employed. Although the spatial antenna correlation is attenuated for multi-polarization configurations, the cross-polar components appear. This paper highlights the impact of depolarization effect on the MIMO channel capacity for a 4&amp;amp;amp;#215;4 uniform linear antenna array. We assume that the channel is unknown at the transmitter and perfectly known at the receiver so that equal power is distributed to each of the transmit antennas. The numerical results illustrate that for low depolarization and spatial correlation, the capacity of single-polarization configuration behaves better than that of multi-polarization configuration. 展开更多
关键词 MULTIPLE-INPUT Multiple-output (MIMO) Channel Capacity Spatial FADING Correlation Multi-polarized Antenna Arrays depolarIZATION Effects.
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Study of Depolarization Field Influence on Ferroelectric Films Within Transverse Ising Model 被引量:2
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作者 TAOYong-Mei SHIQin-Fen JIANGQing 《Communications in Theoretical Physics》 SCIE CAS CSCD 2005年第3期556-560,共5页
An improved transverse Ising model is proposed by taking the depolarization field effect into account. Within the framework of mean-held theory we investigate the behavior of the ferroelectric thin film. Our results s... An improved transverse Ising model is proposed by taking the depolarization field effect into account. Within the framework of mean-held theory we investigate the behavior of the ferroelectric thin film. Our results show that the influence of the depolarization field is to flatten the spontaneous polarization profile and make the films more homogeneous, which is consistent with Ginzburg Landau theory. This fact shows that this model can be taken as an effective model to deal with the ferroelectric film and can be further extended to refer to quantum effect. The competition between quantum effect and depolarization field induces some interesting phenomena on ferroelectric thin films. 展开更多
关键词 ferroelectric films depolarization field transverse Ising model
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Depolarization Effects of Incoherently Scattered Electromagnetic Waves by Inhomogeneous Magnetized Plasma Slab 被引量:1
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作者 George Jandieri Akira I shimaru Vakhtang Jandieri 《Journal of Electromagnetic Analysis and Applications》 2011年第11期471-478,共8页
Scattering of the electromagnetic waves by a randomly inhomogeneous electrically gyrotropic slab are studied using the perturbation method. Second order statistical moments of the ordinary and extraordinary waves scat... Scattering of the electromagnetic waves by a randomly inhomogeneous electrically gyrotropic slab are studied using the perturbation method. Second order statistical moments of the ordinary and extraordinary waves scattered by the magnetized plasma slab are obtained using the boundary conditions for an arbitrary correlation function of electron density fluctuations. Normalized correlation functions at quasi-longitudinal propagation along the external magnetic field are calculated for the carrier frequency 0.1 MHz and 40 MHz. Isolines of the normalized variance of Faraday angle are constructed for the anisotropic Gaussian correlation function at various anisotropy factors of irregularities. Obtained results are in a good agreement with the experimental data. 展开更多
关键词 Statistical MOMENTS Fluctuations IRREGULARITIES MAGNETIZED Plasma depolarIZATION Scattering
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A Study on The Multi-Antenna Geometrical Depolarization Channel Modeling 被引量:2
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作者 SUN Xuehong YANG Xiaoli +2 位作者 ZENG Zhimin ZHANG Cheng BAI Bing 《China Communications》 SCIE CSCD 2016年第3期105-114,共10页
The traditional geometrical depolarization model that single transmitter to single receiver provides a simple method of polarization channel modeling. It can obtain the geometrical depolarization effect of each path i... The traditional geometrical depolarization model that single transmitter to single receiver provides a simple method of polarization channel modeling. It can obtain the geometrical depolarization effect of each path if known the antenna configuration, the polarization field radiation pattern and the spatial distribution of scatters. With the development of communication technology, information transmission spectrum is more and more scarce. The original model provides only a single channel polarization state, so the information will be limited that the polarization state carries in the polarization modulation. The research is so significance that how to carries polarization modulation information by using multi-antenna polarization state. However, the present study shows that have no depolarization effect model for multi-antenna systems. In this paper, we propose a multi-antenna geometrical depolarization model. On the basis of a single antenna to calculate the depolarization effect of the model, and through simulation to analysis the main factors that influence the depolarization effect. This article provides a multi-antenna geometrical depolarization channel modeling that can applied to large-scale array antenna, and to some extent increase the speed of information transmission. 展开更多
关键词 large-scale array antenna multi-antenna channel modeling depolarization effect cross polarization discrimination
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大规格减速机齿轮用42CrMo4H-V的研究与开发 被引量:1
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作者 赵艳荣 贾俊林 张泽春 《特钢技术》 CAS 2019年第4期36-39,共4页
采用电炉+LF+VD+浇注钢锭+退火+锻造+退火+调质工艺,试生产的φ700mm的42CrMo4H-V调质圆钢,不仅具有高纯净度,良好的低倍、组织等特点,而且具备优良的力学性能指标,为下游减速机齿轮制造业的发展做好原材料基础准备。
关键词 42CrMo4h-v 调质 减速机齿轮
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Depolarization field in relaxor-based ferroelectric single crystals under one-cycle bipolar pulse drive
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作者 Chuan-Wen Chen Yang Xiang +4 位作者 Li-Guo Tang Lian Cui Bao-Qing Lin Wei-Dong Du Wen-Wu Cao 《Chinese Physics B》 SCIE EI CAS CSCD 2019年第12期326-330,共5页
The [001]c-polarized(1-x)Pb(Mg1/3Nb2/3)O3–xPbTiO3(PMN-PT) single crystals are widely used in ultrasonic detection transducers and underwater acoustic sensors. However, the relatively small coercive field( 2 kV/cm) of... The [001]c-polarized(1-x)Pb(Mg1/3Nb2/3)O3–xPbTiO3(PMN-PT) single crystals are widely used in ultrasonic detection transducers and underwater acoustic sensors. However, the relatively small coercive field( 2 kV/cm) of such crystals restricts their application at high frequencies because the driving field will exceed the coercive field. The depolarization field can be considerably larger in an antiparallel direction than in a parallel direction with respect to polarization when the bipolar driving cycle starts. Thus, if the direction of the sine wave signal in the first half cycle is opposite to the polarization direction, then the depolarized domains can be repolarized in the second half of the sine cycle. However, if the direction of the sine wave signal in the first half of the cycle is along the polarization direction, then the change is negligible,and the domains switched in the second half of the sine cycle cannot be recovered. The design of electric driving method needs to allow the use of a large applied field to emit strong enough signals and produce good images. This phenomenon combined with the coercive field increases with the driving frequency, thereby making the PMN-PT single crystals usable for high-frequency applications. As such, the applied field can be considerably larger than the conventionally defined coercive field. 展开更多
关键词 piezoelectric crystal coercive field depolarization field bipolar pulse
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Numerical simulation study on spin resonant depolarization due to spin-orbit coupling
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作者 蓝杰钦 徐宏亮 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第8期295-301,共7页
The spin polarization phenomenon in lepton circular accelerators had been known for many years. It provides a new approach for physicists to study the spin feature of fundamental particles and the dynamics of spin-orb... The spin polarization phenomenon in lepton circular accelerators had been known for many years. It provides a new approach for physicists to study the spin feature of fundamental particles and the dynamics of spin-orbit coupling, such as spin resonances. We use numerical simulation to study the features of spin under the modulation of orbital motion in an electron storage ring. The various cases of depolarization due to spin-orbit coupling through an emitting photon and misalignment of magnets in the ring are discussed. 展开更多
关键词 spin polarization and resonant depolarization spin orbit coupling spin flip numericalsimulation
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