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Pt-Pd-Ni体系相图与热力学研究进展
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作者 胡洁琼 张巧 +3 位作者 方继恒 谢明 王宝玲 聂陟枫 《贵金属》 CAS 北大核心 2024年第S01期7-13,共7页
铂基催化剂具有活性高、选择性好、电化学稳定性佳等优点,在工业催化和燃料电池领域具有非常重要的地位。然而,由于成本较高、可用性较低限制了其实际发展。因此,有必要优化铂基催化剂的利用率,设计低成本和高稳定性的铂基催化剂。本研... 铂基催化剂具有活性高、选择性好、电化学稳定性佳等优点,在工业催化和燃料电池领域具有非常重要的地位。然而,由于成本较高、可用性较低限制了其实际发展。因此,有必要优化铂基催化剂的利用率,设计低成本和高稳定性的铂基催化剂。本研究首先介绍了在燃料电池催化剂领域具有应用前景的Pt-Pd-Ni系合金电催化剂的发展和研究现状,然后详细介绍了Pt-Pd-Ni体系的三个二元系相图与热力学评估数据和研究进展,并对Pt-Pd-Ni三元系的一些实验研究进展和今后的研究工作提出展望,对不同相结构对催化性能的影响进行了分析和讨论。通过Pt-Pd-Ni系相图和相结构等的研究将为燃料电池用新型贵金属合金催化材料的设计及工业应用奠定理论和实验基础。 展开更多
关键词 燃料电池催化剂 Pt-pd-Ni体系 合金相图 热力学 有序-无序转变
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Pt-Pd体系的热力学评估
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作者 张金华 主余亮 +2 位作者 权凯栋 史爱文 刘欣 《贵金属》 CAS 北大核心 2024年第3期46-51,共6页
采用CALPHAD(计算相图)方法首先对Pt-Pd体系各相吉布斯自由能分别建模,通过拟合热力学实验数据,获得两套热力学参数。该参数可用于相组分、相图相变、希尔凝固路径及微观组织结构演化模拟等研究领域,利于高性能合金成分设计。针对Pt-Pd... 采用CALPHAD(计算相图)方法首先对Pt-Pd体系各相吉布斯自由能分别建模,通过拟合热力学实验数据,获得两套热力学参数。该参数可用于相组分、相图相变、希尔凝固路径及微观组织结构演化模拟等研究领域,利于高性能合金成分设计。针对Pt-Pd体系中面心立方相(Fcc)混溶间隙是否存在的争论,基于最新的实验数据,使用Thermo-calc软件中的Parrot模块分别对两种情况进行热力学优化。通过优化获得的两套自洽的热力学参数,计算并比较了两种情况下的吉布斯自由能,证实了实验中发现的混溶间隙处于一种亚稳态。Fcc亚稳相图提供了混溶间隙范围内的相组成信息,平衡相图预测的热力学性质则与实验数据高度一致。 展开更多
关键词 相图 热力学优化 混溶间隙 Pt-pd体系
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乙烯气相法制醋酸乙烯Pd-Au催化剂研究进展
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作者 任栎 张向辉 +5 位作者 王光永 陈鹏 李克兵 丁明月 姚佩 赵安民 《低碳化学与化工》 CAS 北大核心 2024年第3期30-41,共12页
醋酸乙烯(VAc)是重要的化工原料,具有良好的应用价值。随着光伏行业的迅速发展以及环保要求的提升,我国对高品质醋酸乙烯(即乙烯气相法醋酸乙烯)的需求逐年增加,开发高催化活性、高目标产物选择性、高稳定性以及低成本的乙烯气相法制醋... 醋酸乙烯(VAc)是重要的化工原料,具有良好的应用价值。随着光伏行业的迅速发展以及环保要求的提升,我国对高品质醋酸乙烯(即乙烯气相法醋酸乙烯)的需求逐年增加,开发高催化活性、高目标产物选择性、高稳定性以及低成本的乙烯气相法制醋酸乙烯Pd-Au催化剂具有重要意义。首先,综述了乙烯气相法制醋酸乙烯催化剂的发展,概述了Pd-Au催化剂的载体、活性组分以及醋酸钾助剂的作用,分析了乙烯气相法制醋酸乙烯的两种反应机理和Pd-Au催化剂的失活原因,阐述了由浸渍法制得蛋壳型Pd-Au催化剂的制备过程。然后,总结了研究者为进一步提高催化性能、降低催化剂成本在催化剂改进方面的研究成果,包括载体改性和异型化,以及活性组分的浸渍、陈化、还原、水洗及干燥等步骤的改进。最后,提出了未来乙烯气相法醋酸乙烯催化剂的研究方向。 展开更多
关键词 醋酸乙烯 乙烯气相法 pd-Au催化剂 催化剂改进
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Fast-Lock Low-Jitter PLL with a Simple Phase-Frequency Detector 被引量:3
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作者 陈莹梅 王志功 章丽 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2008年第1期88-92,共5页
A fast-locking, low-jitter, phase-locked loop (PLL) with a simple phase-frequency detector is proposed. The phase-frequency detector is composed of only two XOR gates. It simultaneously achieves low jitter and short... A fast-locking, low-jitter, phase-locked loop (PLL) with a simple phase-frequency detector is proposed. The phase-frequency detector is composed of only two XOR gates. It simultaneously achieves low jitter and short locking time. The voltage-controlled oscillator within the PLL consists of four-stage ring oscillators which are coupled to each other and oscillate with the same frequency and a phase shift of 45. The PLL is fabricated in 0. 1Stem CMOS technology. The measured phase noise of the PLL output at 500kHz offset from the 5GHz center frequency is - 102.6dBc/Hz. The circuit exhibits a capture range of 280MHz and a low RMS jitter of 2.06ps. The power dissipation excluding the output buffers is only 21.6roW at a 1.8V supply. 展开更多
关键词 phase locked loop phase-frequency detector voltage-controlled oscillator JITTER locking time
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Robust CMOS phase frequency detector for high speed and low jitter charge pump PLL
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作者 周建政 王志功 《Journal of Southeast University(English Edition)》 EI CAS 2008年第1期15-19,共5页
In order to improve the performance of the existing phase frequency detectors (PFDs), a systematical analysis of the existing PFDs is presented. Based on the circuit architecture, both classifications and comparison... In order to improve the performance of the existing phase frequency detectors (PFDs), a systematical analysis of the existing PFDs is presented. Based on the circuit architecture, both classifications and comparisons are made. A new robust CMOS phase frequency detector for a high speed and low jitter charge pump phrase-locked loop (PLL) is designed. The proposed PFD consists of two rising-edge triggered dynamic D flip-flops, two positive-edge detectors and delaying units and two OR gates. It adopts two reset mechanisms to avoid the LIP and DN signals to be logic-1 simultaneously. Thus, any current mismatch of the charge pump circuit will not worsen the performance of the PLL. Furthermore, it has hardly any dead-zone phenomenon in phase characteristic. Simulations with ADS are performed based on a TSMC 0. 18-μm CMOS process with a 1.8-V supply voltage. According to the theoretical analyses and simulation results, the proposed PFD shows a satisfactory performance with a high operation frequency (≈ 1 GHz), a wide phase-detection range [ ± 2π], a near zero dead-zone ( 〈 0. 1 ps), high reliability, low phase jitter, low power consumption ( ≈100 μW) and small circuit complexity. 展开更多
关键词 phase frequency detectors DEAD-ZONE blind-zone phase characteristic frequency characteristic
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Design of 0.5V low-voltage phase and frequency detector for frequency synthesizer in wireless sensor networks
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作者 王利丹 李智群 李伟 《Journal of Southeast University(English Edition)》 EI CAS 2011年第1期8-12,共5页
Based on 0.13μm complementary metal-oxide-semiconductor(CMOS) technology,a phase and frequency detector(PFD) is designed with a low supply voltage of 0.5V for frequency synthesizers used in wireless sensor netwo... Based on 0.13μm complementary metal-oxide-semiconductor(CMOS) technology,a phase and frequency detector(PFD) is designed with a low supply voltage of 0.5V for frequency synthesizers used in wireless sensor networks(WSNs).The PFD can compare the frequency and phase differences of input signals and deliver a signal voltage proportional to the difference.Low threshold transistors are used in the circuits since a power supply of 0.5V is adopted.A pulse latched structure is also used in the circuits in order to increase both the detection range of phase errors and the maximum operation frequency.In experiments,a phase error with a range from-358° to 358° is measured when the input signal frequency is 2MHz.The PFD has a faster acquisition speed compared with conventional digital PFDs.When the input signals are at a frequency of 2MHz with zero phase error,the circuits have a power consumption of 1.8[KG*8]μW,and the maximum operation frequency is 1.25GHz. 展开更多
关键词 phase and frequency detector(PFD) low threshold transistor pulse latch
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An all-optical phase detector by amplitude modulation of the local field in a Rydberg atom-based mixer 被引量:3
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作者 Xiu-Bin Liu Feng-Dong Jia +8 位作者 Huai-Yu Zhang Jiong Mei Wei-Chen Liang Fei Zhou Yong-Hong Yu Ya Liu Jian Zhang Feng Xie Zhi-Ping Zhong 《Chinese Physics B》 SCIE EI CAS CSCD 2022年第9期254-259,共6页
Recently,a Rydberg atom-based mixer was developed to measure the phase of a radio frequency(RF)field.The phase of the signal RF(SIG RF)field is down-converted directly to the phase of a beat signal created by the pres... Recently,a Rydberg atom-based mixer was developed to measure the phase of a radio frequency(RF)field.The phase of the signal RF(SIG RF)field is down-converted directly to the phase of a beat signal created by the presence of a local RF(LO RF)field.In this study,we propose that the Rydberg atom-based mixer can be converted to an all-optical phase detector by amplitude modulation(AM)of the LO RF field;that is,the phase of the SIG RF field is related to both the amplitude and phase of the beat signal.When the AM frequency of the LO RF field is the same as the frequency of the beat signal,the beat signal will further interfere with the AM of the LO RF field inside the atom,and then the amplitude of the beat signal is related to the phase of the SIG RF field.The amplitude of the beat signal and the phase of the SIG RF field show a linear relationship within the range of 0 toπ/2 when the phase of the AM is set with a differenceπ/4 from the phase of the LO RF field.The minimum phase resolution can be as small as 0.6°by optimizing the experimental conditions according to a simple theoretical model.This study will expand and contribute to the development of RF measurement devices based on Rydberg atoms. 展开更多
关键词 quantum sensor phase detector Rydberg atoms micorwave electromagnetically induced transparency amplitude modulation
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ROOM TEMPERATURE AND 750℃ ISOTHERMAL SECTION OF Ag-Pd-Gd(Gd≤25 AT.-%)PHASE DIAGRAM 被引量:1
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作者 ZHANG Kanghou CHEN Lili Kunming Institute of Precious Metals,Kunming,China ZHANG Kanghou,Kunming Institute of Precious Metals,Kunming 650221,China 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 1990年第8期131-133,共3页
The room temperature section and the 750℃ isothermal section of the Ag-Pd-Gd ternary phase diagram containing 0—25 at.-% Gd are constructed by X—ray diffraction analysis and optical microscopy.Each section consists... The room temperature section and the 750℃ isothermal section of the Ag-Pd-Gd ternary phase diagram containing 0—25 at.-% Gd are constructed by X—ray diffraction analysis and optical microscopy.Each section consists of 3 single phase regions,3 bi-phase regions and I tri-phase region respectively. 展开更多
关键词 Ag-pd-Gd ternary system phase diagram
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Design of Digital Multi-Radian Phase Detector on J-TEXT
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作者 李俊 杨州军 +2 位作者 高丽 刘明海 庄革 《Plasma Science and Technology》 SCIE EI CAS CSCD 2014年第10期974-977,共4页
A real time system used to detect phase difference between two sinusoidal signals is proposed in this paper. The system is designed to process the phase signal of the far-infrared (FIR) hydrogen cyanide (HCN) inte... A real time system used to detect phase difference between two sinusoidal signals is proposed in this paper. The system is designed to process the phase signal of the far-infrared (FIR) hydrogen cyanide (HCN) interferometer on J-TEXT. It is based on zero-crossing detection and makes use of the digital circuit. Compared with a traditional zero-crossing phase detector, it doesn't need to sacrifice the time resolution to expand the phase range. The phase difference is divided into two parts, the integer part and the fraction part. In each detecting cycle, they are detected separately. It outputs digital signals that are more stable for transmission. A prototype was built on J-TEXT using discrete components. A practical method is proposed to deal with the counting error caused by the deviation of electronic components in manufacture. Reasonable results were obtained on the prototype. The phase resolution reaches 2π/64 in test, and can still be improved by raising the clock frequency. 展开更多
关键词 phase detector multi-radian DIGITAL HCN interferometer
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在4H晶相Au纳米带上外延生长非常规晶相4H-Pd基合金纳米结构用于高效甲醇电催化氧化
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作者 汪婕 刘贵高 +11 位作者 韵勤柏 周希琛 刘效治 陈也 程洪飞 葛一瑶 黄京韬 胡兆宁 陈博 范战西 谷林 张华 《物理化学学报》 SCIE CAS CSCD 北大核心 2023年第10期110-116,共7页
Pd基合金纳米材料通常具有传统的面心立方(fcc)晶相。本文以密排六方4H相Au(4H-Au)纳米带为模板,外延生长非常规4H晶相的PdFe、PdIr和PdRu,形成4H-Au@PdM(M=Fe、Ir和Ru)核壳合金纳米带。合成的4H-Au@PdFe纳米带被用于碱性环境中甲醇电... Pd基合金纳米材料通常具有传统的面心立方(fcc)晶相。本文以密排六方4H相Au(4H-Au)纳米带为模板,外延生长非常规4H晶相的PdFe、PdIr和PdRu,形成4H-Au@PdM(M=Fe、Ir和Ru)核壳合金纳米带。合成的4H-Au@PdFe纳米带被用于碱性环境中甲醇电催化氧化反应(MOR)的催化剂,表现出优越的质量活性(3.69 A·mgPd^(−1)),分别为Pt/C和Pd黑催化剂质量活性的2.4和10.5倍,也跻身于最好的Pd基和Pt基MOR电催化剂之列。这一策略为合理设计和可控合成具有非常规晶相的多金属纳米结构提供了策略,从而为深入研究多金属纳米结构晶相依赖的性质和应用提供了可能。 展开更多
关键词 纳米材料相工程 晶相 4H相 pd基合金 甲醇氧化反应
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Design of IREDM System with a DSP Phase Detector
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作者 LIUJianguo WEIQingnong 《Semiconductor Photonics and Technology》 CAS 1997年第2期154-157,共4页
The design and realization of a new generation of infra-red electronic distance measurement (IR EDM) system are presented.A DSP(Digital Signal Process) phase detector based on high speed analog-to-digital converter an... The design and realization of a new generation of infra-red electronic distance measurement (IR EDM) system are presented.A DSP(Digital Signal Process) phase detector based on high speed analog-to-digital converter and DSP technique has been designed,in order to improve the precision and reliability of IR EDM system.As a result,the EDM system developed with a DSP phase detector has a precision of 3 mm in the measuring range of 2 km. 展开更多
关键词 Analogue-digital Conversion Distance Measurement DSP phase detector
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700℃ ISOTHERMAL SECTION OF THE Pd-Ru-Gd PARTIAL PHASE DIAGRAM
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作者 K.H Zhang and L.L. Chen (Institute of Precious Metals, Kunming 650221, China) 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 1996年第5期329-332,共4页
The 700℃ isothermal section of the Pd-Ru-Gd partial ternary phase diagram containing more palladium than ruthenium was determined by X-rag diffraction analysis and optical microscopy. The section consists of seven si... The 700℃ isothermal section of the Pd-Ru-Gd partial ternary phase diagram containing more palladium than ruthenium was determined by X-rag diffraction analysis and optical microscopy. The section consists of seven single-phase regions,eleven two-phase regions and five three-phase regions. A new ternary compound Pd2RuGd2,which exhibits a tetragonal structure with a=0.7492 nm and c=0.7445 nm, has been found. 展开更多
关键词 PALLADIUM RUTHENIUM GADOLINIUM phase diagram pd-Ru-Gd ternary sgstem
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Pd/CeO_(2)对2,4-二氯苯氧乙酸的液相催化加氢脱氯
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作者 牛夕阳 余诗慧 +1 位作者 杨娇娇 周娟 《东华大学学报(自然科学版)》 CAS 北大核心 2023年第2期136-143,149,共9页
采用NaBH4还原法分别制备了不同载体CeO_(2)、活性炭(AC)和石英砂(SiO_(2))的负载型Pd基催化剂。采用Zeta电位、X射线衍射、透射电子显微镜等手段对催化剂进行表征,并利用高活性Pd/CeO_(2)催化剂对2,4-二氯苯氧乙酸(2,4-D)进行液相加氢... 采用NaBH4还原法分别制备了不同载体CeO_(2)、活性炭(AC)和石英砂(SiO_(2))的负载型Pd基催化剂。采用Zeta电位、X射线衍射、透射电子显微镜等手段对催化剂进行表征,并利用高活性Pd/CeO_(2)催化剂对2,4-二氯苯氧乙酸(2,4-D)进行液相加氢脱氯反应研究。研究结果表明:载体对催化剂活性影响较大,其中Pd/CeO_(2)催化剂具有高等电点、较强的金属-载体相互作用以及Pd颗粒高分散度的活性特征;Pd/CeO_(2)催化剂对2,4-D的脱氯效果随Pd负载量增加而增加,随pH值的增加呈现先升高后降低的趋势;Pd/CeO_(2)催化剂对2,4-D的加氢脱氯反应符合Langumir-Hinshelwood模型,表明2,4-D在催化剂表面的吸附是反应的速率控制步骤,且Pd/CeO_(2)对不同的污染物都表现出较高的液相加氢还原活性。 展开更多
关键词 液相催化加氢脱氯 2 4-二氯苯氧乙酸 pd/CeO_(2) NaBH_(4)还原法
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Passive round-robin differential-quadrature-phase-shift quantum key distribution scheme with untrusted detectors
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作者 Hongwei Liu Wenxiu Qu +3 位作者 Tianqi Dou Jipeng Wang Yong Zhang Haiqiang Ma 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第10期208-215,共8页
In this paper, we proposed the scheme for a passive round-robin differential-phase-shift quantum key distribution(RRDPS-QKD) set-up based on the principle of Hong–Ou–Mandel interference. Our scheme requires two le... In this paper, we proposed the scheme for a passive round-robin differential-phase-shift quantum key distribution(RRDPS-QKD) set-up based on the principle of Hong–Ou–Mandel interference. Our scheme requires two legitimate parties to prepare their signal state with two different non-orthogonal bases instead of single in original protocol. Incorporating this characteristic, we establish the level of security of our protocol under the intercept-resend attack and demonstrate its detector-flaw-immune feature. Furthermore, we show that our scheme not only inherits the merit of better tolerance of bit errors and finite-sized-key effects but can be implemented using hardware similar to the measurement device independent QKD(MDI-QKD). This ensures good compatibility with the current commonly used quantum system. 展开更多
关键词 quantum key distribution round-robin-differential-phase-shift untrusted detector
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用于苯部分加氢制环己烯的Pd-Co/γ-Al_(2)O_(3)深度脱硫剂制备与性能评价
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作者 董森 李倩 +2 位作者 郭学华 刘树俊 侯莉 《工业催化》 CAS 2023年第3期44-48,共5页
采用液相原位还原法制备三维纳米网状结构的Pd-Co/γ-Al_(2)O_(3)脱硫剂,并用于苯深度脱硫反应体系。通过XRD、SEM、TEM等对催化剂的组成、结构和形貌进行表征,对比不同物质的量比Pd-Co/γ-Al_(2)O_(3)脱硫剂对苯深度脱硫反应的影响。... 采用液相原位还原法制备三维纳米网状结构的Pd-Co/γ-Al_(2)O_(3)脱硫剂,并用于苯深度脱硫反应体系。通过XRD、SEM、TEM等对催化剂的组成、结构和形貌进行表征,对比不同物质的量比Pd-Co/γ-Al_(2)O_(3)脱硫剂对苯深度脱硫反应的影响。结果表明,具有三维网状结构的Pd-Co/γ-Al_(2)O_(3)脱硫剂,可显著提高脱硫剂的比表面积,使其表面活性位点变多。同时,生成的Pd-Co固溶体具有双金属协同吸附作用,改善了脱硫剂的脱硫性能,因此在大幅减少贵金属Pd用量前提下,脱硫剂硫容提高了37%。 展开更多
关键词 催化化学 pd-Co/γ-Al_(2)O_(3)脱硫剂 液相原位还原 三维网状结构 深度脱硫 苯部分加氢
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Partial phase diagram of Pd-Ag-Ru-Gd quaternary system
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作者 张康侯 徐云 《广东有色金属学报》 2005年第2期149-155,共7页
On the basis of the Ag-Pd-Gd, Ag-Ru-Gd and Pd-Ru-Gd ternary systems, the partial phase diagram of Pd-Ag-Ru-Gd(Gd<25% atom fraction) quaternary system has been studied by means of X-ray diffraction analysis, diffe... On the basis of the Ag-Pd-Gd, Ag-Ru-Gd and Pd-Ru-Gd ternary systems, the partial phase diagram of Pd-Ag-Ru-Gd(Gd<25% atom fraction) quaternary system has been studied by means of X-ray diffraction analysis, differential thermal analysis, electron probe microanalysis and optical microscopy. The 700℃ isothermal sections of the Ag-Pd-5Ru-Gd, Ag-Pd-20Ru-Gd and Ag-Pd-50Ru-Gd (Gd≤25% atom fraction) phase diagrams were determined respectively. And the 700℃ isothermal section of the Pd-Ag-Ru-Gd (Gd≤25% atom fraction) quaternary system phase diagram was finally inferred. The section consists of four single-phase regions: solid solution Pd(Ag), (Ru), Pd3Gd and Ag 51 Gd 14 ; five two-phase regions: Pd(Ag)+(Ru), Pd(Ag)+ Ag 51 Gd 14 , (Ru)+ Ag 51 Gd 14 , Pd(Ag)+ Pd3Gd and (Ru)+ Pd3Gd; three three-phase regions: Pd(Ag)+ Pd3Gd+(Ru), Pd(Ag)+ Ag 51 Gd 14 +(Ru) and (Ru)+ Ag 51 Gd 14 + Pd3Gd; one four-phase region Pd(Ag)+ (Ru)+ Ag 51 Gd 14 + Pd3Gd. No new quaternary intermetallic phase is found. 展开更多
关键词 合金 二元结构 四位体 金属互化物
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基于二相码的PD雷达解模糊及遮挡方法
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作者 严济鸿 张欢 +2 位作者 倪伟涵 杨礼 何子述 《系统工程与电子技术》 EI CSCD 北大核心 2023年第6期1667-1674,共8页
为避免二相编码脉冲多普勒(pulse Doppler,PD)雷达的速度以及距离模糊,采用高脉冲重复频率工作(high pulse repetition frequency,HPRF)模式,并在多个脉冲间采用互相关峰值较低的二相编码信号,在接收端对多个发射脉冲间的回波信号进行... 为避免二相编码脉冲多普勒(pulse Doppler,PD)雷达的速度以及距离模糊,采用高脉冲重复频率工作(high pulse repetition frequency,HPRF)模式,并在多个脉冲间采用互相关峰值较低的二相编码信号,在接收端对多个发射脉冲间的回波信号进行数据重排,然后进行脉冲压缩、动目标检测,最终得到的峰值可无模糊体现目标的速度和距离。为减小PD雷达的工作盲区,采用了小的发射脉冲时间宽度,即二相编码信号的码片长度;为避免PD雷达的发射脉冲遮挡,采用两种HPRF发射正交二相编码脉冲信号。仿真结果验证了所提方法的有效性和可行性。 展开更多
关键词 脉冲多普勒雷达 二相编码信号 距离速度模糊 遮挡
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基于异类相使理论的PD-L1阻断药联合扶正中药治疗肺癌探析
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作者 肖依 徐晓晨 +7 位作者 孙英 宁天芳 叶海燕 王坤 赵国静 胡海波 陶红卫 陆学超 《光明中医》 2023年第11期2098-2100,共3页
机体的免疫功能在肺癌的发生发展过程中具有重要意义。PD-1/PD-L1信号通路的激活可形成免疫抑制性肿瘤微环境,导致免疫逃逸的发生。中医药在调节免疫微环境,提高机体免疫力等方面疗效确切。基于中医“异类相使”的配伍理论,针对肺癌患... 机体的免疫功能在肺癌的发生发展过程中具有重要意义。PD-1/PD-L1信号通路的激活可形成免疫抑制性肿瘤微环境,导致免疫逃逸的发生。中医药在调节免疫微环境,提高机体免疫力等方面疗效确切。基于中医“异类相使”的配伍理论,针对肺癌患者气、血、阴、阳不足进行辨证施治,采用具有扶正功效的药物与PD-L1阻断药物相结合,可为中医药防治肿瘤的研究提供新思路。 展开更多
关键词 肺癌 异类相使理论 pd-1/pd-L1信号通路 免疫治疗
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一种适用于亚采样锁相环的高鲁棒性辅助锁定电路
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作者 张磊 林敏 《工业控制计算机》 2024年第10期124-125,128,共3页
当前的研究表明,基于亚采样相位检测器(Sub-Sampling Phase Detectors,SSPD)的锁相环(Phase-Locked Loop,PLL)相较传统锁相环架构可以实现显著降低的带内相位噪声。然而,在片上系统(Systems on Chip,SOCs)应用中,PLL容易受到衬底或电源... 当前的研究表明,基于亚采样相位检测器(Sub-Sampling Phase Detectors,SSPD)的锁相环(Phase-Locked Loop,PLL)相较传统锁相环架构可以实现显著降低的带内相位噪声。然而,在片上系统(Systems on Chip,SOCs)应用中,PLL容易受到衬底或电源耦合的干扰,这很可能会导致PLL失去锁定,且可能无法恢复。针对此问题,提出一种将辅助锁频环(Frequency-Locked Loop,FLL)和数字锁定检测器(Digital Lock Detector,DLD)相结合的适用于亚采样锁相环(Sub-Sampling Phase-Locked Loop,SSPLL)的高鲁棒性辅助锁定电路。仿真结果表明:与传统SSPLL相比,所提出的电路极大提升了PLL对衬底或电源干扰的鲁棒性,同时保持了其低相位噪声的优点,这对于SSPLL在大规模生产和应用中的可靠性具有重要意义。 展开更多
关键词 亚采样相位检测器 锁频环 数字锁定检测器 锁相环
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低抖动电荷泵锁相环设计及其Simulink建模仿真
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作者 蔡俊 王勇 《宜春学院学报》 2024年第6期28-34,共7页
随着集成电路工艺技术的进步,电路工作频率越来越高,对时钟信号的抖动和相噪也提出了更高的要求。针对锁相环电路参数多、结构复杂、瞬态仿真耗时长等问题,通过建立电荷泵锁相环系统环路数学模型,并运用MATLAB/Simulink对其进行负反馈... 随着集成电路工艺技术的进步,电路工作频率越来越高,对时钟信号的抖动和相噪也提出了更高的要求。针对锁相环电路参数多、结构复杂、瞬态仿真耗时长等问题,通过建立电荷泵锁相环系统环路数学模型,并运用MATLAB/Simulink对其进行负反馈系统建模,实现对电荷泵锁相环的快速动态仿真。在TSMC 65 nm CMOS工艺节点下,完成了锁相环的电路设计、版图绘制、物理验证并提取寄生参数及后仿真,得到一款典型值:输入频率为30 MHz,锁定频率1.5 GHz的低抖动电荷泵锁相环。后仿真结果表明该PLL电路性能指标良好,在典型值条件下,PLL的锁定时间为10μs,锁定时峰峰值抖动为2.68 ps,时钟信号占空比为45%。 展开更多
关键词 锁相环 鉴相鉴频器 电荷泵 压控振荡器
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