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IMPACTS OF PENETRATION THERAPY WITH HEAD ELECTRICAL ACUPUNCTURE ON PROLIFERATION OF NEURAL STEM CELLS IN SUBSTANTIA NIGRA OF RAT MODEL OF PARKINSON'S DISEASE 被引量:2
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作者 王顺 戚秀杰 韩迪 《World Journal of Acupuncture-Moxibustion》 2008年第4期23-31,共9页
Objective To probe into the function mechanism of penetration therapy with head electrical acupuncture on Parkinson's disease. Methods Microinjection of 6-hydroxydopamin (6-OHDA) on the left cor- pus striatum was a... Objective To probe into the function mechanism of penetration therapy with head electrical acupuncture on Parkinson's disease. Methods Microinjection of 6-hydroxydopamin (6-OHDA) on the left cor- pus striatum was adopted to prepare rotation model of Parkinson^s disease in rat. Penetration therapy with head electrical acupuncture was administered in treatment. Normal group, sham-operation group, model group and penetration therapy group were set up. (1)lmmunohistochemical (IHC) method was used to test the morphology and count of positive cell of tyrosine hydroxylase (TH). (2)RT-PCR technology was used to detect the expression of nestin mRNA of neural stem cell (NSC). Results (1)Compared with model group, in pene- tration therapy group, the expressions of TH-positive neurons in immune response were increased in areal density (AD), numerical density (ND) and integrating optic density (P〈0.05). (2)Compared with model group, in penetration therapy group, the expression of nestin mRNA was increased (P〈0. 05). Conclusion Penetration therapy with head electrical acupuncture promotes the proliferation of endogenous neural stem cells in substantia nigra of rat model of Parkinson's disease. 展开更多
关键词 penetration therapy with head electrical acupuncture Parkinson's disease DA neuron
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Simulation of Mine Electrical Penetration Technology 被引量:5
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作者 LIU Zhi-xin YUE Jian-hua LIU Shu-cai 《Journal of China University of Mining and Technology》 EI 2007年第3期326-329,共4页
Based on the principle of electrical penetration, the reflection characteristics of collapse columns at different locations of a working face is numerically simulated by using a 3D finite element method. The data coll... Based on the principle of electrical penetration, the reflection characteristics of collapse columns at different locations of a working face is numerically simulated by using a 3D finite element method. The data collected by the electrical penetration is processed and interpreted using “tunnel penetration” which is similar to radio wave penetration. Reflection characteristics of collapse columns at different locations below floors of coal seams are analyzed, providing a new paradigm and a theoretical foundation for processing and interpreting electrical penetration data. The tomography analysis is made based on data simulation and calculation results and alltransmitting-receiving points are analyzed for their corresponding maximum attenuation values and maximum absorption coefficients. On the basis of this, a new method for precisely interpreting the spatial positions of geological anomalous bodies is suggested. The simulation shows that 1) the detection result of both roof and floors of the working face by electrical penetration is a volumetric effect and 2) there exists a corresponding relation between the detection depth and the working face width, with the op- timal detection depth within 40% of the workin face width. 展开更多
关键词 numerical simulation DC electrical penetration audio-frequency electrical penetration
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Obtaining 2D Soil Resistance Profiles from the Integration of Electrical Resistivity Data and Standard Penetration Test (SPT) and Light Dynamic Penetrometer (DPL) Resistance Tests—Applications in Mass Movements Studies
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作者 Cassiano Antonio Bortolozo Tatiana Sussel Gonçalves Mendes +10 位作者 Mariana Ferreira Benessiuti Motta Silvio Jorge Coelho Simões Tristan Pryer Daniel Metodiev Marcio Roberto Magalhães de Andrade Maiconn Vinicius de Moraes Danielle Silva de Paula Nélio José Bastos Luana Albertani Pampuch Rodolfo Moreda Mendes Marcio Augusto Ernesto de Moraes 《International Journal of Geosciences》 2023年第9期840-854,共15页
In Brazil and various regions globally, the initiation of landslides is frequently associated with rainfall;yet the spatial arrangement of geological structures and stratification considerably influences landslide occ... In Brazil and various regions globally, the initiation of landslides is frequently associated with rainfall;yet the spatial arrangement of geological structures and stratification considerably influences landslide occurrences. The multifaceted nature of these influences makes the surveillance of mass movements a highly intricate task, requiring an understanding of numerous interdependent variables. Recent years have seen an emergence in scholarly research aimed at integrating geophysical and geotechnical methodologies. The conjoint examination of geophysical and geotechnical data offers an enhanced perspective into subsurface structures. Within this work, a methodology is proposed for the synchronous analysis of electrical resistivity geophysical data and geotechnical data, specifically those extracted from the Light Dynamic Penetrometer (DPL) and Standard Penetration Test (SPT). This study involved a linear fitting process to correlate resistivity with N10/SPT N-values from DPL/SPT soundings, culminating in a 2D profile of N10/SPT N-values predicated on electrical profiles. The findings of this research furnish invaluable insights into slope stability by allowing for a two-dimensional representation of penetration resistance properties. Through the synthesis of geophysical and geotechnical data, this project aims to augment the comprehension of subsurface conditions, with potential implications for refining landslide risk evaluations. This endeavor offers insight into the formulation of more effective and precise slope management protocols and disaster prevention strategies. 展开更多
关键词 GEOPHYSICS Geotechnical Data electrical Resistivity Method Standard penetration Test (SPT) Light Dynamic penetrometer (DPL) Mass Movements
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Gaseous Penetration of Pr into PbTiO_3 Ceramics and Their Electric Properties 被引量:1
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作者 杨雪梅 郝素娥 韦永德 《Journal of Rare Earths》 SCIE EI CAS CSCD 2004年第4期483-485,共3页
The gaseous Pr-penetration is a new method to modify ceramics, which is expected to be a promising method for producing new conductor ceramic materials. The gaseous penetration of Pr into PbTiO_3 ceramics and their im... The gaseous Pr-penetration is a new method to modify ceramics, which is expected to be a promising method for producing new conductor ceramic materials. The gaseous penetration of Pr into PbTiO_3 ceramics and their improved electric properties were reported. Through XRD, EPMA and SEM analysis,it is confirmed that the gaseous penetration makes Pr enter into PbTiO_3 ceramics, and the new compound of Pr_2Ti_2O_7 is formed by the penetration of Pr in the gaseous state. The formed new Pr_2Ti_2O_7-PbTiO_3 ceramic materials have a significant change in electric properties. The room temperature resistivity decreases from 2.0×10^(10) Ω·m to 9.487 Ω·m. The grain resistance and the grain boundary resistance decrease with increase in temperature, and the PTCR effect disappears. The tendency of transition to a conductive body is manifest. 展开更多
关键词 functional materials PbTiO_3 ceramics gaseous penetration electric properties rare earths
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Effects of the penetration temperature on structure and electrical conductivity of samarium modified BaTiO_3 powders 被引量:4
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作者 付东升 郝素娥 +1 位作者 李佳龙 强亮生 《Journal of Rare Earths》 SCIE EI CAS CSCD 2011年第2期164-167,共4页
Gaseous penetration technique was adopted to improve the electrical conductivity of BaTiO3 powders and the effects of penetration temperature on the structure and electrical conductivity of Sm-modified BaTiO3 powders ... Gaseous penetration technique was adopted to improve the electrical conductivity of BaTiO3 powders and the effects of penetration temperature on the structure and electrical conductivity of Sm-modified BaTiO3 powders were studied.It was observed that the penetration of Sm made the resistivity of BaTiO3 powders decrease with the increase in the penetration temperature and decreased to the lowest point of 4.20×102 ?·m when the penetration temperature was 950 oC.The relationship curve of the temperature and resistivity of the samples was also established preliminarily to get the mathematical expression by the fitting method.Through X-ray diffraction (XRD) analysis,the new phases of Sm2O3 and Ba4Ti2O27 were detected.It was indicated that intricate reactions related to Sm took place during the penetration process and led to the Ti-rich state of the system.The Fourier transform infrared (FTIR) spectrum illustrated that the bonds of Ti–O octahedron was strengthened by substitution of Sm3+ at Ti4+ sites,which led to the growth of Ti:Ba ratio.The analysis results of scanning electron microscopy (SEM) indicated that the particle size of Sm-modified BaTiO3 powders progressed with the penetration temperature increasing. 展开更多
关键词 gaseous penetration BATIO3 SAMARIUM electrical conductivity rare earths
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用RCPT研究功能梯度混凝土抗氯离子渗透性能
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作者 周万良 陈俊 +6 位作者 高升 孙鑫梁 尚世豪 王淦 白江航 高鹏 赵卫平 《实验技术与管理》 CAS 北大核心 2024年第4期32-38,共7页
用非稳态迁移法(NSSM)和自然浸泡法评定功能梯度混凝土(FGC)的抗氯离子渗透性能都存在局限性,但快速氯离子渗透试验法(RCPT)没有局限性。该研究用RCPT法对基于各种胶凝材料的FGC的电通量进行了大量测试并得到如下结论:提出了FGC的电通... 用非稳态迁移法(NSSM)和自然浸泡法评定功能梯度混凝土(FGC)的抗氯离子渗透性能都存在局限性,但快速氯离子渗透试验法(RCPT)没有局限性。该研究用RCPT法对基于各种胶凝材料的FGC的电通量进行了大量测试并得到如下结论:提出了FGC的电通量计算公式;FGC的电通量反映了FGC的抗氯离子渗透性能,FGC的电通量越低则其抗氯离子渗透性能越高;碱激发矿渣(AAS)砂浆具有极好的抗氯离子渗透性能,其氯离子渗透系数可低至2.1×10^(–13)m^(2)/s。 展开更多
关键词 功能梯度混凝土 快速氯离子渗透试验 电通量 氯离子渗透 碱激发矿渣
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高压电脉冲破碎非均质花岗岩数值模拟
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作者 祝效华 陈梦秋 刘伟吉 《中国石油大学学报(自然科学版)》 EI CAS CSCD 北大核心 2024年第5期151-159,共9页
对高压电脉冲破碎机制的研究是提高钻井破岩效率和优化电脉冲电参数的关键。利用颗粒流离散元软件及Voronoi划分建立非均匀介电性质的花岗岩模型,从电流场、电路场、电击穿场进行等离子通道生长过程仿真,并分析非均质度对击穿路径的影响... 对高压电脉冲破碎机制的研究是提高钻井破岩效率和优化电脉冲电参数的关键。利用颗粒流离散元软件及Voronoi划分建立非均匀介电性质的花岗岩模型,从电流场、电路场、电击穿场进行等离子通道生长过程仿真,并分析非均质度对击穿路径的影响;对比不同花岗岩的电破岩效率和电脉冲破岩效果。结果表明:花岗岩的非均质度增大使得初始电场极值增大,相应地降低了电破岩的能量需求;等离子通道的生长方向存在优先发展区域,等离子通道的生长过程体现出通道尖端处电场集中现象强于通道躯干处;花岗岩非均质度的差异使得等离子通道的总长度和平均贯穿深度存在显著差异,在一定非均质度范围内电脉冲破碎效果和非均质度呈正相关;不同非均质度花岗岩的单脉冲电破岩效率差异不大,等离子通道的总长度越长,电破岩效率越高。 展开更多
关键词 电脉冲破岩 非均质花岗岩 电击穿 等离子通道钻井 钻井提速
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导电溶液浓度对高压电脉冲煤体致裂增透效果影响实验研究
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作者 陈清 李尧斌 《中国矿业》 北大核心 2024年第2期175-181,共7页
为检验溶液浓度对高压电脉冲煤体致裂增透效果的影响,采用水溶液和浓度分别为0.5 mol/L、1.0 mol/L、1.5 mol/L、2.0 mol/L的NaCl溶液作为导电介质,运用高压脉冲放电系统对相似煤样进行水中放电致裂实验,并采用超声波检测技术分析致裂... 为检验溶液浓度对高压电脉冲煤体致裂增透效果的影响,采用水溶液和浓度分别为0.5 mol/L、1.0 mol/L、1.5 mol/L、2.0 mol/L的NaCl溶液作为导电介质,运用高压脉冲放电系统对相似煤样进行水中放电致裂实验,并采用超声波检测技术分析致裂效果。实验结果表明:采用水作为导电溶液时放电压力峰值为1.26 MPa,而采用NaCl溶液作为导电介质时放电压力峰值明显提升,采用NaCl溶液实验后煤样的首波声时差也高于水溶液实验后煤样的首波声时差,煤样的内部裂隙改造效果更为显著,表明导电溶液的加入可以优化煤样的导电性能;随着导电溶液的浓度增大,放电压力峰值越大,高压电脉冲在一定浓度的NaCl溶液中放电,能够提高电能转化为等离子通道能量的利用率,导电溶液浓度增加可以加强煤样的导电性,优化高压电脉冲放电致裂增透效果;但随着浓度继续升高,相较于1.5 mol/L NaCl溶液,2.0mol/L NaCl溶液放电压力峰值仅由2.20 MPa提升到2.25 MPa,两者首波声时差的变化也不大,煤样的致裂情况相仿,此时煤样对各导电离子的吸附量达到饱和状态,煤样吸附离子的数量基本维持不变,因此,煤样的导电性基本不变。 展开更多
关键词 增透实验 高压电脉冲 导电溶液 裂隙 瓦斯防治
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中医定向透药疗法和中频脉冲电刺激治疗偏瘫肩痛的疗效差异分析
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作者 姜建萍 孙健 赵春苗 《中外医疗》 2024年第16期174-177,共4页
目的 分析偏瘫肩痛患者实施中医定向透药与中频脉冲电刺激治疗的效果。方法 随机选取潍坊市中医院于2022年11月—2023年11月收治的60例偏瘫肩痛患者为研究对象,掷骰子分组为透药组与刺激组,各30例。透药组行中医定向透药治疗,刺激组行... 目的 分析偏瘫肩痛患者实施中医定向透药与中频脉冲电刺激治疗的效果。方法 随机选取潍坊市中医院于2022年11月—2023年11月收治的60例偏瘫肩痛患者为研究对象,掷骰子分组为透药组与刺激组,各30例。透药组行中医定向透药治疗,刺激组行中频脉冲电刺激治疗。比较两组疼痛情况、肩关节活动度、肢体功能情况及有效率。结果 治疗后,透药组疼痛评分低于刺激组,肩关节活动度高于刺激组,上肢功能及上肢自理能力优于刺激组,差异有统计学意义(P均<0.05)。透药组治疗总有效率为96.67%,高于刺激组的76.67%,差异有统计学意义(χ^(2)=5.192,P<0.05)。结论 中医定向透药疗法可大幅减轻肩痛问题,拓展肩关节活动度,提升肩关节功能,有效率高,相比中频脉冲电刺激疗效更好。 展开更多
关键词 中频脉冲电刺激 中医定向透药疗法 肢体功能 偏瘫肩痛
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大熔深K-PAW熔池及电弧视觉行为特征分析研究
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作者 贾传宝 李佳鹏 +2 位作者 陈崇龙 张珂谨 周卫鲁 《电焊机》 2024年第2期1-7,共7页
穿孔等离子弧焊接(K-PAW)以其独特的优势,在中厚板的焊接制造中应用广泛,并逐渐向更大厚度的方向发展。然而,随工件厚度增加熔池穿孔出现不稳定等问题,制约了其在实际生产中的应用。分析了14 mm厚304不锈钢在“受控恒定穿孔”控制策略... 穿孔等离子弧焊接(K-PAW)以其独特的优势,在中厚板的焊接制造中应用广泛,并逐渐向更大厚度的方向发展。然而,随工件厚度增加熔池穿孔出现不稳定等问题,制约了其在实际生产中的应用。分析了14 mm厚304不锈钢在“受控恒定穿孔”控制策略下的大熔深K-PAW熔池特征尺寸变化规律和焊接过程中的熔池行为。通过视觉检测与电信号同步采集系统,对大熔深K-PAW过程中熔池的形貌特征进行定量分析,探究在受控脉冲条件下的熔池特征参数变化情况,以及熔池特征与电信号的同步动态行为规律。以初始电流270 A进行焊接,在起弧的前14 s的盲孔阶段,随着电弧热量积累,熔池不稳定,尺寸出现震荡,最大震荡幅度超过10 mm,同时熔池长宽比也在1.0~1.6范围内变化;随着穿孔于第15 s发生,熔池达到平衡,且长宽比在19 s时达到峰值;维孔阶段,熔池保持稳定,形状未发生大变化。综上,可以通过熔池形状变化趋势来区分焊接阶段。比较了不同焊接电流(280 A、275 A、270 A)的盲孔阶段,发现采用较大的初始电流有利于缩短盲孔时间,由270 A时的22.9 s减小到了280 A时的19.8 s,并降低焊接气孔出现的可能性。最后,发现电弧中心与熔池前边缘的距离可以反映穿孔状态。结果验证了“受控恒定穿孔”控制策略的可行性,并验证了通过视觉特征判断焊接阶段及是否穿孔的可行性。 展开更多
关键词 穿孔等离子弧焊接 深熔焊 熔池视觉特征参数 视电信号同步
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考虑电力-交通交互的配电网故障下电动汽车充电演化特性 被引量:4
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作者 吴赋章 杨军 +3 位作者 柯松 向慕超 凌在汛 邓桂平 《电力系统自动化》 EI CSCD 北大核心 2024年第5期88-98,共11页
由于配电网与交通网间的耦合交互作用,高渗透率电动汽车接入下的配电网故障可能对两网的运行产生扩大影响,厘清故障下电动汽车充电负荷对电网和交通网运行状态的影响以及充电站充电负荷分布是及时阻断故障影响的基础。针对此,提出了考... 由于配电网与交通网间的耦合交互作用,高渗透率电动汽车接入下的配电网故障可能对两网的运行产生扩大影响,厘清故障下电动汽车充电负荷对电网和交通网运行状态的影响以及充电站充电负荷分布是及时阻断故障影响的基础。针对此,提出了考虑电力-交通交互的配电网故障下充电特征演化分析方法。首先,考虑配电网故障下充电负荷变化对配电网的影响,提出了计及充电负荷变化灵敏度的变步长重复潮流模型以计算配电网最大供电能力。其次,结合用户有限理性决策和动态交通均衡,构建了配电网故障影响下的交通运行状态演化模型。进一步,以电动汽车出行和充电为耦合单元,基于改进的Davidson函数描述供电能力对充电行为的影响,建立了两网交互的作用关系。最后,仿真分析了考虑网络耦合的配电网故障下充电负荷演化规律及其影响。 展开更多
关键词 高渗透率 电动汽车 配电网 交通网 故障 充电 最大供电能力
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考虑长周期供需不平衡风险的新型电力系统规划方法 被引量:2
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作者 姜海洋 杜尔顺 +3 位作者 马佳豪 肖晋宇 侯金鸣 张宁 《中国电机工程学报》 EI CSCD 北大核心 2024年第15期5845-5857,I0001,共14页
受高比例新能源并网带来的波动性和间歇性影响,新型电力系统的长周期供需不平衡矛盾日益突出。该文将电力系统的长周期供需不平衡风险分为两部分:连续多日无风无光的极端天气场景和月电量供需不平衡风险。首先,选取连续多日无风无光的... 受高比例新能源并网带来的波动性和间歇性影响,新型电力系统的长周期供需不平衡矛盾日益突出。该文将电力系统的长周期供需不平衡风险分为两部分:连续多日无风无光的极端天气场景和月电量供需不平衡风险。首先,选取连续多日无风无光的极端天气场景,提出基于条件风险价值理论(conditional value at risk,CvaR)的月电量不平衡风险评估模型。在此基础上,提出考虑长周期供需不平衡风险的新型电力系统规划方法,通过季节性储能等灵活性资源的优化配置,可有效提升电力系统的长周期平衡能力。最后,基于IEEE RTS-79算例分析论证了所提方法的有效性,并初步讨论季节性储能在平抑长周期供需不平衡风险方面的作用。 展开更多
关键词 高比例新能源 电力系统规划 极端天气 长周期供需不平衡风险 电力电量平衡 季节性储能
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Insect-specific RNA virus affects the stylet penetration activity of brown citrus aphid(Aphis citricidus)to facilitate its transmission 被引量:1
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作者 Xin An Qiaoying Gu +4 位作者 Jing Wang Tengyu Chang Wei Zhang Jin-Jun Wang Jinzhi Niu 《Insect Science》 SCIE CAS CSCD 2024年第1期255-270,共16页
Sap-sucking insects often transmit plant viruses but also carry insect viruses,which infect insects but not plants.The impact of such insect viruses on insect host biology and ecology is largely unknown.Here,we identi... Sap-sucking insects often transmit plant viruses but also carry insect viruses,which infect insects but not plants.The impact of such insect viruses on insect host biology and ecology is largely unknown.Here,we identified a novel insect-specific virus carried by brown citrus aphid(Aphis citricidus),which we tentatively named Aphis citricidus picornavirus(AcPV).Phylogenetic analysis discovered a monophyletic cluster with AcPV and other unassigned viruses,suggesting that these viruses represent a new family in order Picornavirales.Systemic infection with AcPV triggered aphid antiviral immunity mediated by RNA interference,resulting in asymptomatic tolerance.Importantly,we found that AcPV was transmitted horizontally by secretion of the salivary gland into the feeding sites of plants.AcPV influenced aphid stylet behavior during feeding and increased the time required for intercellular penetration,thus promoting its transmission among aphids with plants as an intermediate site.The gene expression results suggested that this mechanism was linked with transcription of salivary protein genes and plant defense hormone signaling.Together,our results show that the horizontal transmission of AcPV in brown citrus aphids evolved in a manner similar to that of the circulative transmission of plant viruses by insect vectors,thus providing a new ecological perspective on the activity of insect-specific viruses found in aphids and improving the understanding of insect virus ecology. 展开更多
关键词 electrical penetration graph feeding behavior insect virus transmission Picornavirales salivary protein
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LED绿光对小贯小绿叶蝉取食行为的干扰
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作者 乔利 陈磊 +3 位作者 蒋月丽 周洲 耿书宝 王丽娟 《浙江农业学报》 CSCD 北大核心 2024年第9期2051-2059,共9页
小贯小绿叶蝉是我国茶区普遍发生的害虫之一,其为害严重影响了茶叶的产量和品质。为减少化学农药带来的残留,探索茶园叶蝉防治新方法,采用LED绿光(波长520~525 nm)干扰其取食过程,并通过刺吸电位图谱(EPG)仪记录分析不同光照强度和照射... 小贯小绿叶蝉是我国茶区普遍发生的害虫之一,其为害严重影响了茶叶的产量和品质。为减少化学农药带来的残留,探索茶园叶蝉防治新方法,采用LED绿光(波长520~525 nm)干扰其取食过程,并通过刺吸电位图谱(EPG)仪记录分析不同光照强度和照射时间对小贯小绿叶蝉取食行为的影响。结果表明,小贯小绿叶蝉取食过程中所产生的波型有NP波、A波、C波、E波、S波、F波和R波,其中NP波占比最大。与自然光(对照)相比,LED绿光对小贯小绿叶蝉取食行为有明显的抑制作用,相同时间内,光照强度越大,刺吸百分比越低,刺吸次数越多,对小贯小绿叶蝉取食行为的干扰越明显。该研究结果可为灯光防治茶园叶蝉的应用提供技术支持。 展开更多
关键词 LED绿光 取食行为 小贯小绿叶蝉 刺吸电位图谱
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La_2Ti_6O_(15)-CeTi_(21)O_(38)-PbTiO_3 ceramics formed in gaseous penetration of La-Ce into PbTiO_3 and their electric properties 被引量:8
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作者 郝素娥 韦永德 刘新荣 《Science China Chemistry》 SCIE EI CAS 2003年第3期313-319,共7页
The gaseous penetration of La-Ce into PbTiO3 ceramics is reported. The compounds of La2Ti6O15 and CeTi21O38 are formed and the new La2Ti6O15-CeTi21O38-PbTiO3 ceramics are prepared by the penetration of La and Ce in th... The gaseous penetration of La-Ce into PbTiO3 ceramics is reported. The compounds of La2Ti6O15 and CeTi21O38 are formed and the new La2Ti6O15-CeTi21O38-PbTiO3 ceramics are prepared by the penetration of La and Ce in the gaseous state. The new ceramic materials have a significant change in electric properties. The room temperature resistivity decreases from 2.0×1010 to 0.248 Ω. m, and the grain resistance exhibits an obvious PTCR effect with the change of temperature. However, the grain boundary resistance decreases rapidly with increase in temperature. The change rule of the total resistance is similar to that of the grain boundary, and the PTCR effect disappears and the tendency of transition to a conductive body is manifest. The XPS analysis suggests that the particles that are Pb, Ti, La and Ce in La2Ti6O15-CeTi21O38-PbTiO3 ceramics all change their valence and lead to decreasing resistivity, and the bound energy peak values of elements in La2Ti6O15-CeTi21O38-PbTiO3 ceramics are also reported. The La2Ti6O15-CeTi21O38-PbTiO3 ceramics have a better thermal stability in high temperatures through TG-DTA analysis. 展开更多
关键词 RARE earth PBTIO3 ceramics gaseous penetration electric properties La2Ti6O15 CeTi21O38.
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探地雷达和高密度电法在固废填埋场治理中的应用 被引量:8
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作者 曲彦丞 刘笑笑 +3 位作者 郭朋 张景宇 李典超 张燕挥 《工程地球物理学报》 2024年第1期35-43,共9页
某些垃圾填埋场由于相关资料严重缺失,给污染物的治理工作带来了困难。为了解决老垃圾填埋场的污染物治理问题,将高密度电法和探地雷达法相结合,对某村老垃圾填埋场进行了全方位探查,取得了以下成果:1)成功识别出垃圾与原位土层的界线,... 某些垃圾填埋场由于相关资料严重缺失,给污染物的治理工作带来了困难。为了解决老垃圾填埋场的污染物治理问题,将高密度电法和探地雷达法相结合,对某村老垃圾填埋场进行了全方位探查,取得了以下成果:1)成功识别出垃圾与原位土层的界线,得到了垃圾层的范围和厚度,并以此为基础计算出回填方量为132454 m ^(3),为污染物的清除和治理提供了重要的参考;2)依据电阻率的分布,划分出填埋物的种类主要为建筑垃圾、生活垃圾或者粪便;3)识别出垃圾渗液的污染范围,圈定需要隔绝污染和回收清洁土壤的位置。本次研究结果为今后的垃圾治理工作提供了重要的参考。 展开更多
关键词 高密度电阻率法 探地雷达法 垃圾填埋场 污染物治理
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基于三探针检测的TC4钛合金激光深熔焊等离子体动态行为研究
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作者 张涵博 杨立军 +2 位作者 田云付 黄一鸣 王颖 《焊接学报》 EI CAS CSCD 北大核心 2024年第11期101-109,共9页
在激光深熔焊中,激光诱导等离子体的产生具有很强的随机性和时变性.利用新型无源三探针电信号采集装置,采集高时间分辨率的等离子体电信号,获得大样本的等离子体温度等热力学信息,采用无监督学习方法中的K-均值聚类对复杂的等离子体动... 在激光深熔焊中,激光诱导等离子体的产生具有很强的随机性和时变性.利用新型无源三探针电信号采集装置,采集高时间分辨率的等离子体电信号,获得大样本的等离子体温度等热力学信息,采用无监督学习方法中的K-均值聚类对复杂的等离子体动态行为聚类分析.结果表明,在文中试验条件下,等离子体的喷发频率主要集中在1240-2200 Hz范围,等离子体喷发的温度变化率主要分布在5000-30000 K/ms的范围内;等离子体的摆动频率主要在1050-1410 Hz范围,等离子体摆动的温度变化率主要分布在200-2000 K/ms的范围内,喷发和摆动的温度变化率差异明显. 展开更多
关键词 激光深熔焊 电信号 等离子体动态行为 K-均值聚类
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基于刺探电位技术的四个枸杞品种对棉蚜的抗性评价
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作者 马银香 王新谱 《昆虫学报》 CAS CSCD 北大核心 2024年第2期213-222,共10页
【目的】明确4个枸杞品种对棉蚜Aphis gossypii的抗性差异,以探明抗虫因子及位点,并筛选抗蚜枸杞品种。【方法】利用刺吸电位图谱(electrical penetration graph, EPG)技术记录棉蚜成蚜在4个枸杞品种(宁杞1号、宁杞5号、宁杞7号和宁杞10... 【目的】明确4个枸杞品种对棉蚜Aphis gossypii的抗性差异,以探明抗虫因子及位点,并筛选抗蚜枸杞品种。【方法】利用刺吸电位图谱(electrical penetration graph, EPG)技术记录棉蚜成蚜在4个枸杞品种(宁杞1号、宁杞5号、宁杞7号和宁杞10号)上的取食行为,并利用室内抗蚜性鉴定和聚类分析相结合的方法对不同枸杞品种对棉蚜成蚜的抗性进行综合评价。【结果】棉蚜成蚜在取食4个枸杞品种时呈现出Np, A, G, B, C, Pd, E和F波8种波形。在棉蚜成蚜的取食过程中,E1总持续时间在宁杞1号上最长,在宁杞5号和宁杞7号上次之,在宁杞10号上最短;E2波持续时间以在宁杞10号上最长,在宁杞1号上最短;F波持续时间在宁杞1号上最长,在宁杞10号上最短,在宁杞5号和宁杞7号上的F波持续时间介于前两者之间,说明宁杞1号的机械抗性较强,而宁杞10号机械抗性较弱。通过抗蚜性的鉴定和聚类分析,将4个枸杞品种归为3类,第Ⅰ类:宁杞1号,为高抗蚜品种;第Ⅱ类:宁杞5号和宁杞7号,为抗蚜品种;第Ⅲ类:宁杞10号,为感蚜品种。【结论】棉蚜在4个枸杞品种上的取食行为存在差异,且4个枸杞品种的抗虫机制和位点也存在差异,宁杞1号在叶表皮、叶肉和韧皮部对棉蚜表现出抗性,抗蚜性最强,为高抗蚜品种;宁杞5号和宁杞7号在叶肉和韧皮部对棉蚜表现出抗性,但抗蚜性较弱,为抗蚜品种;宁杞10号能够被棉蚜长时间刺吸取食,其抗蚜性最弱,为感蚜品种。 展开更多
关键词 棉蚜 枸杞 取食行为 品种选育 抗蚜性 刺吸电位技术
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An electropenetrography waveform library for the probing and ingestion behaviors of Culex tarsalis on human hands
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作者 Anastasia M.W.Cooper Samuel B.Jameson +4 位作者 Victoria Pickens Cameron Osborne Elaine A.Backus Kristopher Silver Dana N.Mitzel 《Insect Science》 SCIE CAS CSCD 2024年第4期1165-1186,共22页
Culex tarsalis Coquillett(Diptera:Culicidae)mosquitoes are capable of vectoring numerous pathogens affecting public and animal health.Unfortunately,the probing behaviors of mosquitoes are poorly understood because the... Culex tarsalis Coquillett(Diptera:Culicidae)mosquitoes are capable of vectoring numerous pathogens affecting public and animal health.Unfortunately,the probing behaviors of mosquitoes are poorly understood because they occur in opaque tissues.Electropenetrography(EPG)has the potential to elucidate these behaviors by recording the electrical signals generated during probing.We used an AC–DC EPG with variable input resistors(Ri levels)to construct a waveform library for Cx.tarsalis feeding on human hands.Biological events associated with mosquito probing were used to characterize waveforms at four Ri levels and with two electrical current types.The optimal settings for EPG recordings of Cx.tarsalis probing on human hands was an Ri level of 10^(7)Ohms using an applied signal of 150 millivolts alternating current.Waveforms for Cx.tarsalis included those previously observed and associated with probing behaviors in Aedes aegypti L.(Diptera:Culicidae):waveform families J(surface salivation),K(stylet penetration through the skin),L(types 1 and 2,search for a blood vessel/ingestion site),M(types 1 and 2,ingestion),N(type 1,an unknown behavior which may be a resting and digestion phase),and W(withdrawal).However,we also observed variations in the waveforms not described in Ae.aegypti,which we named types L3,M3,M4,and N2.This investigation enhances our understanding of mosquito probing behaviors.It also provides a new tool for the automated calculation of peak frequency.This work will facilitate future pathogen acquisition and transmission studies and help identify new pest and disease management targets. 展开更多
关键词 AC-DC blood feeders electrical penetration graph EPG human hands MOSQUITOES waveform library
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Future penetration and impacts of electric vehicles on transport energy consumption and CO_2 emissions in different Chinese tiered cities 被引量:2
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作者 ZHANG Qian OU XunMin ZHANG XiLiang 《Science China(Technological Sciences)》 SCIE EI CAS CSCD 2018年第10期1483-1491,共9页
This study focuses on the penetration of electric vehicles(EVs) within the private passenger vehicle market in selected Chinese cities categorized into different tiers. It presents an analysis of factors driving the m... This study focuses on the penetration of electric vehicles(EVs) within the private passenger vehicle market in selected Chinese cities categorized into different tiers. It presents an analysis of factors driving the market diffusion of EVs and the reasons for varying results across the investigated cities and provides estimates of related EV impacts on local energy consumption and CO_2 emissions. A nested multinomial model incorporating technological attributes of vehicles, energy prices, charging conditions,and incentive policies was developed for conducting a scenario analyses covering six cities. The results indicated that in a stagnation scenario in which policy support was absent, the market share of electric vehicles would be less than 7% in all six cities under investigation by 2030. In medium growth and rapid growth scenarios, the market share of EVs across the six cities was projected to be within the ranges of 29%–68% and 49%–80%, respectively. The impacts of EVs on gasoline demand depended not just on their cumulative sales but also on the share of electrified vehicle distance, and the CO_2 emission reduction effect was influenced by local EV stocks and the mix of local electricity sources. Battery costs, charging conditions, and energy prices were primary driving factors. Charging conditions and energy prices were key reasons for differences in the penetration curves among cities. These driving factors were further affected by differences in local income levels, housing and parking conditions, and availability of land resources. Subsidies were found to be effective in the short term, whereas in the medium term,tax breaks could serve as the main monetary incentive. In the long term, national policy should focus on technology-related R&D, whereas local policies should focus on the operational phase and be tailored to specific local situations. 展开更多
关键词 clean vehicles electric vehicle penetration CO2 emissions China
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