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多孔n-GaN/p-Zn_(x)Cu_(1-x)S异质结的制备及紫外探测性能研究
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作者 杜志伟 贾伟 +5 位作者 贾凯达 任恒磊 李天保 董海亮 贾志刚 许并社 《人工晶体学报》 CAS 北大核心 2024年第8期1326-1336,共11页
本文首先采用紫外光辅助电化学刻蚀(UV-EC)方法制备出了孔隙密度为1.51×10^(10)cm^(-2)、平均孔径为38 nm的多孔n-GaN薄膜;随后在其上通过水浴法沉积了一系列Zn_(x)Cu_(1-x)S复合薄膜,x为0.0、0.2、0.4、0.6、0.8、1.0,形成的多孔n... 本文首先采用紫外光辅助电化学刻蚀(UV-EC)方法制备出了孔隙密度为1.51×10^(10)cm^(-2)、平均孔径为38 nm的多孔n-GaN薄膜;随后在其上通过水浴法沉积了一系列Zn_(x)Cu_(1-x)S复合薄膜,x为0.0、0.2、0.4、0.6、0.8、1.0,形成的多孔n-GaN/p-Zn_(x)Cu_(1-x)S异质结带隙在2.34~3.51 eV调控;最后基于这些异质结构建出p-n结型紫外探测器。I-V曲线结果表明这些探测器均具有良好的整流特性,特别是n-GaN/p-Zn_(0.4)Cu_(0.6)S探测器性能最优。在暗态下,I_(+3 V)/I_(-3 V)约为1.78×10^(5);在偏压为-3 V、光功率密度为432μW/cm^(2)(365 nm)的条件下,光暗电流比超过10^(3),上升/下降时间为0.09/39.8 ms,响应度(R)为0.352 A/W,外量子效率(EQE)为119.6%,探测率(D^(*))为3.21×10^(12)Jones。I-t曲线结果表明,多孔n-GaN/p-Zn_(x)Cu_(1-x)S异质结紫外探测器在连续开-关光循环过程中拥有稳定的光电流响应。该研究为制备异质结紫外探测器提供了一定的理论指导和实验数据。 展开更多
关键词 p-Zn_(x)Cu_(1-x)s 多孔n-Gan 异质结 紫外探测器 光暗电流比 响应度
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元素分析-同位素质谱测定δ^(15)N和δ^(34)S的信号强度响应特征
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作者 杜屹原 杨斌 +4 位作者 孟宪菁 温日红 宋亮 张嫒萍 周晓 《同位素》 CAS 2023年第2期159-167,I0003,共10页
自然界中不同类型样品C、N和S元素含量以及C/N和C/S的差异极大,导致元素分析-同位素比值质谱仪(EA-IRMS)联机系统的进样量和检测信号强度的变化范围极大。进样量和信号强度对EA-IRMS测定δ^(15)N和δ^(34)S的影响将导致样品测量结果具... 自然界中不同类型样品C、N和S元素含量以及C/N和C/S的差异极大,导致元素分析-同位素比值质谱仪(EA-IRMS)联机系统的进样量和检测信号强度的变化范围极大。进样量和信号强度对EA-IRMS测定δ^(15)N和δ^(34)S的影响将导致样品测量结果具有较大的不确定性。为应对样品中目标元素含量低或样品稀缺等限制,本研究重点关注EA-IRMS测定δ^(15)N和δ^(34)S的信号强度依赖性特征。结果表明,EA-IRMS在小元素进样量或弱信号强度条件下测定δ^(15)N和δ^(34)S需要进行空白校正。在1.71~561.93μg N和3.74~100.62μg S的进样条件下,同位素标准物质δ^(15)N和δ^(34)S的测定误差变化范围分别为0.18‰~0.54‰和0.21‰~0.88‰,测定精度变化范围分别为0.24‰~0.57‰和0.27‰~0.54‰。该联机系统对高C/N和C/S(>200)木材标准物质测定时,其δ^(15)N平均误差为0.34‰,其δ^(34)S的测定精度为0.58‰。此外,对两种木材样品δ^(15)N的连续(6~20 d)测定证明该联机系统的测定结果具有较好的时间稳定性。该研究可为EA-IRMS技术的应用与发展提供数据参考。 展开更多
关键词 同位素比值质谱仪(IRMs) 碳氮比 碳硫比 木材 信号强度
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Improving S/N ratio for pre-stack seismic data from western China 被引量:2
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作者 Guo Ping Zhang Wenpo Gao Yan Zhao Jun Gao Shumei 《Applied Geophysics》 SCIE CSCD 2007年第3期207-213,共7页
The seismic data from western China is very noisy. Two main reasons are static corrections and low S/N ratio problems. By seismic data processing and study these problems have been effectively solved by iterating the ... The seismic data from western China is very noisy. Two main reasons are static corrections and low S/N ratio problems. By seismic data processing and study these problems have been effectively solved by iterating the static corrections and improving the S/N ratio for pre-stack seismic data. Suppression and elimination of various other distortions has been implemented as well. Due to the fact that the S/N ratio is improved, the resolution of the seismic data is also improved. 展开更多
关键词 static correction low s/n ratio REsOLUTIOn
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S/N Ratio of 4-Channel A/D Geological Radar Non-uniform Sampling Signals 被引量:2
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作者 MA Kai SU Hong-qi 《Journal of China University of Mining and Technology》 EI 2007年第4期534-536,共3页
Using the quantitative error probability density method we studied the S/N ratio of alternately sampled signals digitized by a 4-channel A/D. A complete expression for the S/N ratio of a 4-channel A/D non-uniform samp... Using the quantitative error probability density method we studied the S/N ratio of alternately sampled signals digitized by a 4-channel A/D. A complete expression for the S/N ratio of a 4-channel A/D non-uniform sampling signal was deduced. First we obtained an expression for the S/N ratio of a 1-channel A/D uniform sampling signal when the sampling frequency was equal to or greater than 2 times the frequency of the sampled signal. Based on the S/N ratio of a 2-channel A/D,alternating,non-uniform sampling signal,we analyzed the distribution of quantitative error using the quantitative error probability density method and the distribution convolution formula. From this the S/N ratio expression of a 4-channel A/D sampling signal was deduced. The simulation result shows that the deduced expression is correct. 展开更多
关键词 geological radar 4-channel non-uniform sampling sum distribution s/n ratio
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Design of flying vehicle control system by signal to noise ratio
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作者 孙龙大 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2001年第1期63-68,共6页
Presents the new concept of ″Desired to be small″ based on the basic function of vehicle flight control system for an optimal design of flying vehicle control system, and the definition of S/N ratio and calculation ... Presents the new concept of ″Desired to be small″ based on the basic function of vehicle flight control system for an optimal design of flying vehicle control system, and the definition of S/N ratio and calculation formula for ″Desired to be small″ dynamic characteristics, and the S/N ratio method established for design of velicle flight control systems, by which, an orthogrnal table is used to arrange test schemes, and error facters are used to simulate various interferences, and the use of S/N ratio as a design criterion to synthesise the design of dynamic and static characteristics for definition of an optimal scheme, the application of S/N ratio method to the design of a type of vehicle control system and the single run success abtained in design of control system, technical evaluation test and design finalization flight test. 展开更多
关键词 s/n ratio method control system dynamic characteristics static characteristics parameter design
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Comparison of the S-, N- or P-Deprivations’ Impacts on Stomatal Conductance, Transpiration and Photosynthetic Rate of Young Maize Leaves 被引量:1
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作者 Dimitris L. Bouranis Styliani N. Chorianopoulou +4 位作者 Alexandros Dionias Giouli Sofianou Aristotelis Thanasoulas Georgios Liakopoulos Dimosthenis Nikolopoulos 《American Journal of Plant Sciences》 2012年第8期1058-1065,共8页
Seven-day-old maize (Zea mays) plants were grown hydroponically for ten days in deprived nutrient solutions against the corresponding control grown under full nutrition;the effects of S-, N- or P-deprivation on lamina... Seven-day-old maize (Zea mays) plants were grown hydroponically for ten days in deprived nutrient solutions against the corresponding control grown under full nutrition;the effects of S-, N- or P-deprivation on laminas’ mean stomatal conductance (gs), transpiration rate (E) and photosynthetic rate (A) were monitored, along with the impact on the laminas’ total dry mass (DM), water amount (W), length and surface area (Sa). Furthermore, a time series analysis of each parameter’s response ratios (Rr), i.e. the treatment’s value divided by the corresponding control’s one, was performed. Under S-deprivation, the Rr of laminas’ mean gs, E, and A presented oscillations within a ±15% fluctuation zone, notably the “control” zone, whilst those of laminas’ total DM, water amount, surface area, and length included oscillation during the first days and deviation later on, presenting deviation during d10. Under the N-deprivation conditions all Rr time courses except the A one, included early deviations from the control zone without recovering. The deviation from the control zone appeared at d4. Under P-deprivation, all Rr time courses represented oscillations within the control zone. P-deprivation’s patterns resembled those of S-deprivation. Compared to the one of the S-deprivation, the P-one’s oscillations took place within a broader zone. Linear relationships among the various Rr patterns were found between gs-E, gs-A, E-A, DM-W and DM-Sa. In conclusion, the impact of P-deprivation appeared in an early stage and included an alleviation action, the one of N-deprivation appeared early with no alleviation action, whilst that of S-deprivation appeared later, being rather weaker when compared to the impact of the P-deprivation’s impact. 展开更多
关键词 s-Deprivation n-Deprivation P-Deprivation Hydroponics Zea Mays sTOMATAL Conductance TRAnsPIration RATE Photosynthetic RATE Response ratios Fluctuation Analysis
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The Effect of Tool Construction and Cutting Parameters on Surface Roughness and Vibration in Turning of AISI 1045 Steel Using Taguchi Method
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作者 Rogov Vladimir Aleksandrovich Ghorbani Siamak 《Modern Mechanical Engineering》 2014年第1期8-18,共11页
This paper presents an experimental investigation focused on identifying the effects of cutting conditions and tool construction on the surface roughness and natural frequency in turning of AISI1045 steel. Machining e... This paper presents an experimental investigation focused on identifying the effects of cutting conditions and tool construction on the surface roughness and natural frequency in turning of AISI1045 steel. Machining experiments were carried out at the lathe using carbide cutting insert coated with TiC and two forms of cutting tools made of AISI 5140 steel. Three levels for spindle speed, depth of cut, feed rate and tool overhang were chosen as cutting variables. The Taguchi method L9 orthogonal array was applied to design of experiment. By the help of signal-to-noise ratio and analysis of variance, it was concluded that spindle speed has the significant effect on the surface roughness, while tool overhang is the dominant factor affecting natural frequency for both cutting tools. In addition, the optimum cutting conditions for surface roughness and natural frequency were found at different levels. Finally, confirmation experiments were conducted to verify the effectiveness and efficiency of the Taguchi method in optimizing the cutting parameters for surface roughness and natural frequency. 展开更多
关键词 surface ROUGHnEss Cutting Condition natural Frequency VIBration TURnInG AnOVA Taguchi Method s/n ratio
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臭氧胁迫对水稻生长以及C、N、S元素分配的影响 被引量:22
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作者 郑飞翔 王效科 +3 位作者 侯培强 张巍巍 逯非 欧阳志云 《生态学报》 CAS CSCD 北大核心 2011年第6期1479-1486,共8页
采用开顶式气室(Open-top Chamber,OTC),对水稻"3694繁"(Oryza sativa L.,3694 Fan)在浙江嘉兴进行田间原位臭氧(O3)熏气实验,研究不同臭氧浓度熏气对水稻生长以及C、N、S元素分配的影响。实验设置分4个水平:过滤大气组(CF,10... 采用开顶式气室(Open-top Chamber,OTC),对水稻"3694繁"(Oryza sativa L.,3694 Fan)在浙江嘉兴进行田间原位臭氧(O3)熏气实验,研究不同臭氧浓度熏气对水稻生长以及C、N、S元素分配的影响。实验设置分4个水平:过滤大气组(CF,10nL/L)、自然大气组(NF,40 nL/L)和两个不同浓度的臭氧处理组(O3-1:100 nL/L;O3-2:150 nL/L)。主要结果表明:(1)开始臭氧熏气时,各个处理组单茎水稻各组分生物量没有差异.在熏气后期(水稻成熟期),臭氧处理使单茎水稻根、茎和穗生物量显著下降,根冠比降低,株高显著降低,表明臭氧胁迫增加水稻地上部分的干物质分配,且对株高的影响可能大于对地上生物量的影响;(2)臭氧处理使水稻根和茎C元素含量下降,叶C元素含量上升,表明臭氧胁迫提高了叶片中碳分配,而降低了根和茎的碳分配;(3)各个组分N元素含量上升和碳氮比下降;(4)茎、叶和穗S元素含量上升,可能会增强水稻抗氧化系统的作用,从而抵抗臭氧胁迫。所有实验结果表明臭氧浓度升高会对水稻生长产生严重不利影响,从而导致水稻各个组分的C、N、S元素分配格局发生改变。 展开更多
关键词 臭氧 水稻 生长 C n s 碳氮比
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进水N/S值对同步脱硫反硝化特性的影响 被引量:8
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作者 徐金兰 侯圣春 黄廷林 《中国给水排水》 CAS CSCD 北大核心 2010年第7期1-4,共4页
研究了不同进水N/S值条件下,不同接种物的厌氧体系的同步脱硫反硝化特性。结果表明:在N/S为0.6或0.4的条件下,3个体系对硫化物的去除率均达到90%以上,其中以进水N/S为0.4时产生的悬浮态硫最多;硝态氮的去除特性与硫化物不同,3个体系对... 研究了不同进水N/S值条件下,不同接种物的厌氧体系的同步脱硫反硝化特性。结果表明:在N/S为0.6或0.4的条件下,3个体系对硫化物的去除率均达到90%以上,其中以进水N/S为0.4时产生的悬浮态硫最多;硝态氮的去除特性与硫化物不同,3个体系对硝态氮的去除率均在进水N/S为1.0时达到100%,且此时N2的产量也最大。可见,尽管同步脱硫反硝化工艺具备同时脱氮及除硫的能力,但其进水N/S的控制值却不相同。对于脱硫而言,最佳的进水N/S为0.4;对于脱氮而言,最佳的进水N/S为1.0。此外,研究发现3个不同接种物的厌氧体系对硫化物及硝态氮的去除途径不同,进水N/S值的影响也有差异。对于接种了厌氧污泥的体系,存在自养反硝化和异养反硝化的竞争,改变进水N/S值可调节二者的竞争,高N/S值会抑制硫化物自养反硝化过程,降低对硫化物的去除率;对于接种脱氮硫杆菌的纯菌体系,多硫自催化反应会与硫化物自养反硝化反应竞争硫化物,降低对硝态氮的去除率,高N/S值会导致出水硝态氮浓度较高;对于添加脱氮硫杆菌的强化厌氧污泥体系,以硫化物自养反硝化过程为主,最佳的N/S为0.4。 展开更多
关键词 同步脱硫反硝化 进水n/s 接种物
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一种复合材料层合板的S—N曲线模型 被引量:14
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作者 吴富强 姚卫星 《机械强度》 CAS CSCD 北大核心 2004年第z1期127-129,共3页
基于纤维增强复合材料疲劳机理和试验数据 ,文中给出一个描述纤维增强复合材料拉—拉疲劳的S—N曲线模型。此模型同时考虑复合材料受载方向的静抗拉强度、纤维静强度、疲劳载荷应力比等诸多因素对S—N曲线的影响 。
关键词 复合材料 疲劳寿命 s-n曲线 应力比 静强度
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一般应力比时焊接结构S-N曲线的预测方法 被引量:2
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作者 管德清 《工程力学》 EI CSCD 1996年第4期89-96,共8页
本文考虑了焊接结构的几何形状、受载形式、应力比、残余应力、尺寸效应以及材料等因素对疲劳寿命的影响,利用Peterson公式和极值疲劳切口系数概念,建立了一般应力比时焊接结构S-N曲线的预估模型.文中对几类典型的焊接结... 本文考虑了焊接结构的几何形状、受载形式、应力比、残余应力、尺寸效应以及材料等因素对疲劳寿命的影响,利用Peterson公式和极值疲劳切口系数概念,建立了一般应力比时焊接结构S-N曲线的预估模型.文中对几类典型的焊接结构的S-N曲线进行了预测,预测值与实验结果符合较好.本文方法可以大量减少疲劳实验,具有一定的工程实用价值. 展开更多
关键词 焊接结构 s-n曲线 疲劳强度 应力比
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7B50铝合金板材疲劳极限强度及S-N曲线的测定 被引量:6
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作者 刘平 《铝加工》 CAS 2017年第3期26-30,共5页
采用成组法及升降法针对航天用材料7B50铝合金厚板L-T向试样进行高周疲劳强度研究与测定,摸索材料中值疲劳强度的S-N疲劳寿命曲线的绘制方法,测定出关键材料7B50合金板材的疲劳寿命曲线。
关键词 s-n 曲线 成组法 升降法 中值疲劳强度 疲劳极限 应力比
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基于恒寿命疲劳结合S-N曲线的弹簧疲劳寿命分析 被引量:6
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作者 张明建 《机械研究与应用》 2012年第6期107-108,113,共3页
常规的弹簧疲劳寿命分析,是以弹簧材质的S-N疲劳曲线为依据,根据预期弹簧寿命,反复选择弹簧基本参数,验算达到疲劳强度安全系数≥疲劳许用安全系数,计算工作量大。介绍一种基于恒寿命疲劳结合S-N曲线的简单方法分析弹簧的疲劳寿命,为提... 常规的弹簧疲劳寿命分析,是以弹簧材质的S-N疲劳曲线为依据,根据预期弹簧寿命,反复选择弹簧基本参数,验算达到疲劳强度安全系数≥疲劳许用安全系数,计算工作量大。介绍一种基于恒寿命疲劳结合S-N曲线的简单方法分析弹簧的疲劳寿命,为提高弹簧质量给出一些参考。 展开更多
关键词 恒寿命疲劳 s-n曲线 变应力 应力比
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同步相机测量任意频率光信号时的S/N理论分析
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作者 刘进元 《光子学报》 EI CAS CSCD 1998年第4期359-361,共3页
本文从理论上分析了同步扫描相机在测量由双波长激光器产生的差频信号时信噪比的问题.这一差频信号的频率和同步相机的扫描频率并非整数倍关系.我们从光电阴极的发射噪音(shotnoise)理论出发,得出了在这种特殊应用情况下相机的信... 本文从理论上分析了同步扫描相机在测量由双波长激光器产生的差频信号时信噪比的问题.这一差频信号的频率和同步相机的扫描频率并非整数倍关系.我们从光电阴极的发射噪音(shotnoise)理论出发,得出了在这种特殊应用情况下相机的信嗓比比正常应用情况下(即入射光脉冲的频率和扫描频率为整数倍关系)至少要小23倍. 展开更多
关键词 同步扫描相机 信噪比 差频信号 光信号
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Eu原子4f^76p_(3/2)ns自电离衰变分支比和弹射电子角分布 被引量:2
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作者 王靖 沈礼 +1 位作者 杨玉娜 戴长建 《原子与分子物理学报》 CAS 北大核心 2018年第3期374-382,共9页
首先运用孤立实激发技术将Eu原子从基态4f^76s^(28)S_(7/2)经中间态4f^76s6p共振激发到4f^76sns Rydberg态,然后再将其进一步激发至4f^76p_(3/2)ns(n=7,8)自电离态.其次,采用速度影像技术对Eu原子自电离弹射出的电子进行探测,以便来研... 首先运用孤立实激发技术将Eu原子从基态4f^76s^(28)S_(7/2)经中间态4f^76s6p共振激发到4f^76sns Rydberg态,然后再将其进一步激发至4f^76p_(3/2)ns(n=7,8)自电离态.其次,采用速度影像技术对Eu原子自电离弹射出的电子进行探测,以便来研究自电离衰变分支比和弹射电子角分布.在研究自电离衰变分支比时,重点讨论了粒子数反转的可能性,并依据此现象可为实现自电离激光器提供有价值的信息.另外,还探讨了各向异性参数对弹射电子角分布的影响;以及在Eu原子不同自电离几率位置处,讨论了弹射电子角分布形状的变化情况. 展开更多
关键词 Eu原子 4f76p3/2ns自电离态 分支比 角分布
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Analysis and Optimization of Operational and Pollutant Attributes of Diesel Engine with CNT-Infused Orange Peel Biodiesel-Diesel Blend Fuel
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作者 Ranjeet RAI R.R.SAHOO 《Journal of Thermal Science》 SCIE EI CAS CSCD 2024年第2期761-778,共18页
The current study is performed to find sustainable solutions for the future of transportation and environmental well-being.Both conventional methods and experimental design table(L16 Orthogonal Array)techniques have b... The current study is performed to find sustainable solutions for the future of transportation and environmental well-being.Both conventional methods and experimental design table(L16 Orthogonal Array)techniques have been employed to examine and optimize a diesel-powered engine's operational and pollutant parameters.The L16 Orthogonal Array is obtained through Taguchi's experimental design approach using Minitab 16 software.The experimental design incorporated three control variables,namely engine speed,fuel type,and engine load,each with four levels.The operational parameters,namely brake thermal efficiency(BTE)and brake specific fuel consumption(BSFC),as well as the emission characteristics,including hydrocarbon(HC),carbon monoxide(CO),nitrogen oxide(NO),and smoke emissions,were acquired using the L16 orthogonal array(OA) and subsequently examined.The utilization of methodologies such as signal-to-noise(S/N) ratio and grey analysis was employed to determine the optimal operational state of the engine to achieve maximum performance while minimizing emissions.The engine's ideal state of operation,in terms of BTE and BSFC,was determined to be at 75% engine load,1000 r/min engine speed,and using 10^(-4)(in vol) carbon nanotube incorporated 20% orange peel biodiesel(OPB20CNT100) blended fuel(A3-B1-C4).The study indicated that engine load significantly influenced BTE and BSFC,with 84.05% and 87.79% contribution factors,respectively.At 25% engine load,1000 r/min,and OPB20CNT100 fuel(A1-B1-C4) CO,smoke,NO,and HC emissions were the lowest.Engine load affects emissions the most.Engine BSFC increased 3.10% and NO emissions 1.77%.BTE,CO,smoke,and HC emissions decreased by 1.9%,12.29%,47.05%,and 47.22%,respectively,at optimal operating conditions concerning diesel fuel.This study shows that Taguchi-Grey's experimental design optimizes diesel engine operational and pollutant attributes.The outcomes revealed that orange peel biodiesel infused with CNT can replace diesel fuel in an environmentally friendly way.This alternative fuel could clean and improve transportation. 展开更多
关键词 Taguchi-Grey method OPB20CnT100 TRAnsEsTERIFICATIOn s/n ratio GRG HC CO and nO
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基于主S-N曲线法的地铁制动箱焊接疲劳分析 被引量:2
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作者 孙权 陈秉智 《计算机辅助工程》 2016年第3期47-51,共5页
为研究地铁车辆制动箱焊接接头的疲劳寿命,根据实际结构建立4节点壳单元有限元模型,给出搭接焊和T型焊的焊缝建模方法.在3种振动工况下,运用主S-N曲线法计算焊缝的等效结构应力和对应损伤比.结果表明:该地铁车辆制动箱焊接结构设计合理... 为研究地铁车辆制动箱焊接接头的疲劳寿命,根据实际结构建立4节点壳单元有限元模型,给出搭接焊和T型焊的焊缝建模方法.在3种振动工况下,运用主S-N曲线法计算焊缝的等效结构应力和对应损伤比.结果表明:该地铁车辆制动箱焊接结构设计合理可靠;通过与实体单元模型计算结果进行对比证明壳单元模拟焊缝的合理性;在不同尺寸单元下对比2种疲劳评估方法,结果表明名义应力法预测疲劳寿命的准确性较低. 展开更多
关键词 地铁制动箱 焊接接头 疲劳 s-n曲曲线法 等效结构应力 损伤比
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Investigation of ductile iron casting process parameters using Taguchi approach and response surface methodology 被引量:3
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作者 A. Johnson Santhosh A. R. Lakshmanan 《China Foundry》 SCIE 2016年第5期352-360,共9页
To find the optimized levels of various casting parameters in the ductile iron casting, various casting defects and the rejection rate were observed from a medium scale foundry. The controlled values of different cast... To find the optimized levels of various casting parameters in the ductile iron casting, various casting defects and the rejection rate were observed from a medium scale foundry. The controlled values of different casting parameters such as pouring temperature, inoculation, carbon equivalent, moisture content, green compression strength, permeability and mould hardness were selected. Three different melts of metal with 0.4wt.%, 0.6wt.%, and 0.8wt.% inoculation (Fe-Si-Mg alloy and post inoculant) were produced using a 1-ton capacity coreless medium frequency induction furnace. L-27 orthogonal array with 3-level settings were chosen for the analysis. Responses for each run were observed. The signal-to-noise (S/N) ratio for each run was calculated using the Taguchi approach, and the optimized levels of different casting parameters were identified based on the SIN ratio. The analysis of variance for the casting acceptance percentage concludes that inoculation is the most significant factor affecting the castings' quality with a contribution percentage of 44%; an increase in inoculation results in a significant improvement in acceptance percentage of ductile iron castings. The experiment results showed that with the optimized parameters, the rejection rate was reduced from 16.98% to 6.07%. 展开更多
关键词 optimized levels casting parameters s/n ratio Taguchi approach AnOVA ‘F’-Test
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The polarization characteristics of single shot nanosecond laser-induced breakdown spectroscopy of Al 被引量:1
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作者 刘佳 陶海岩 +2 位作者 高勋 郝作强 林景全 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第4期281-285,共5页
The polarization-resolved laser-induced breakdown spectroscopy (PRLIBS) technique, which can significantly reduce the polarized emission from laser plasma by placing a polarizer in front of the detector, is a powerf... The polarization-resolved laser-induced breakdown spectroscopy (PRLIBS) technique, which can significantly reduce the polarized emission from laser plasma by placing a polarizer in front of the detector, is a powerful tool to improve the line-to-continuum ratio in LIBS applications. It is shown that the continuum emission from the plasma produced through ablating an Al sample by nanosecond laser pulses is much more polarized than the discrete line emission with the singlepulse PRLIBS technique. The effects of laser fluence and detection angle on the Al polarization spectrum are systematically explored experimentally. The calculated result of the polarization spectrum as a function of laser fluence shows that it is in agreement with the experimental observations. 展开更多
关键词 polarization-resolved laser-induced breakdown spectroscopy laser plasma s/n ratio
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Optimizing electrophoretic deposition conditions for enhancement in electrical conductivity of carbon fiber/carbon nanotube/epoxy hybrid composites 被引量:1
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作者 王一奇 BYUN Joon-hyung +1 位作者 KIM Byung-sun SONG Jung-il 《Journal of Central South University》 SCIE EI CAS 2012年第11期3017-3022,共6页
The effectiveness of optimizing electrical conductivity of carbon fiber/carbon nanotube (CNT)/epoxy hybrid composites via Taguchi method was demonstrated. CNTs were induced on carbon fabric by electrophoretic deposi... The effectiveness of optimizing electrical conductivity of carbon fiber/carbon nanotube (CNT)/epoxy hybrid composites via Taguchi method was demonstrated. CNTs were induced on carbon fabric by electrophoretic deposition (EPD) technique. The essential deposition parameters were identified as l) the deposition time, 2) the deposition voltage, 3) the mass fraction of CNTs in suspension, and 4) the distance between the electrodes. An experimental design was then performed to establish the appropriate levels for each factor. An orthogonal array of L9 (34) was designed to conduct the experiments. Electrical conductivity results were collected as the response. The relative influences of design parameters on the response were discussed. Using the model, signal to noise (S/N) ratio and response characteristics for the optimized deposition parameter combination were predicted. The results show clearly that the optimum condition of electrophoretic deposition (EPD) process improves the electrical conductivity of carbon/epoxy hybrid composites. 展开更多
关键词 design of experiment electrophoretic deposition carbon nanotube Taguchi method signal to noise s/n ratio analysisof variance (AnOVA)
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