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vapor deposition of excellent a-Si:H passivation layers for a-Si:H/c-Si heterojunction solar cells at highpressure and high power

Lei ZHAO,Wenbin ZHANG,Jingwei CHEN,Hongwei DIAO,Qi WANG,Wenjing WANG

《能源前沿（英文）》 2017年第11卷第1期页码 85-91 doi: 10.1007/s11708-016-0437-3

摘要： The intrinsic a-Si:H passivation layer inserted between the doped a-Si:H layer and the c-Si substrate is very crucial for improving the performance of the a-Si:H/c-Si heterojunction (SHJ) solar cell. The passivation performance of the a-Si:H layer is strongly dependent on its microstructure. Usually, the compact a-Si:H deposited near the transition from the amorphous phase to the nanocrystalline phase by plasma enhanced chemical vapor deposition (PECVD) can provide excellent passivation. However, at the low deposition pressure and low deposition power, such an a-Si:H layer can be only prepared in a narrow region. The deposition condition must be controlled very carefully. In this paper, intrinsic a-Si:H layers were prepared on n-type Cz c-Si substrates by 27.12 MHz PECVD at a high deposition pressure and high deposition power. The corresponding passivation performance on c-Si was investigated by minority carrier lifetime measurement. It was found that an excellent a-Si:H passivation layer could be obtained in a very wide deposition pressure and power region. Such wide process window would be very beneficial for improving the uniformity and the yield for the solar cell fabrication. The a-Si:H layer microstructure was further investigated by Raman and Fourier transform infrared (FTIR) spectroscopy characterization. The correlation between the microstructure and the passivation performance was revealed. According to the above findings, the a-Si:H passivation performance was optimized more elaborately. Finally, a large-area SHJ solar cell with an efficiency of 22.25% was fabricated on the commercial 156 mm pseudo-square n-type Cz c-Si substrate with the open-circuit voltage ( ) of up to 0.732 V.

关键词： PECVD high pressure and high power a-Si:H microstructure passivation heterojunction solar cell

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Continuous deacylation of amides in a high-temperature and high-pressure microreactor

《化学科学与工程前沿（英文）》 2022年第16卷第12期页码 1818-1825 doi: 10.1007/s11705-022-2182-y

摘要： The deacylation of amides, which is widely employed in the pharmaceutical industry, is not a fast reaction under normal conditions. To intensify this reaction, a high-temperature and high-pressure continuous microreaction technology was developed, whose space-time yield was 49.4 times that of traditional batch reactions. Using the deacylation of acetanilide as a model reaction, the effects of the temperature, pressure, reaction time, molar ratio of reactants, and water composition on acetanilide conversion were carefully studied. Based on the rapid heating and cooling capabilities, the kinetics of acetanilide deacylation at high temperatures were investigated to determine the orders of reactants and activation energy. This microreaction technology was further applied to a variety of other amides to understand the influence of substituents and steric hindrance on the deacylation reaction.

关键词： amide deacylation microreactor flow chemistry reaction intensification

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A novel high-temperature and high-pressure hydraulic pump based on mononeuron control

Linhui ZHAO, Xin FANG

《机械工程前沿（英文）》 2009年第4卷第2期页码 219-223 doi: 10.1007/s11465-009-0024-y

摘要： Based on structures and characteristics of traditional hydraulic pumps, this paper proposes a novel high-temperature and high-pressure hydraulic pump (HHHP) that can work under 150°C and 28 MPa to overcome problems of traditional high-temperature plunger pumps. The HHHP is designed with the structure of mechanical division and double cylinder parallel. The control signals of two cylinders are two separate triangle waveforms with 90° phase difference. Because the output waveforms of two cylinders have the same characteristics as the control signals, the HHHP can obtain a stable output after two separate waveforms are superposed. A mononeuron self-adaptive PID control algorithm is also improved by modifying parameters and . Two improved controllers are used to control the two cylinders, respectively, making two displacements of plungers match each other. Therefore, reduced fluctuations and stable pressure output is obtained. Besides simulation, tests on the built prototype test system are carried out to verify the performance of HHHP. Results show that the improved control approach can limit fluctuations to a lower level and the HHHP system attains good outputs under different signal periods and different pressures.

关键词： mononeuron PID control hydraulic pump pressure fluctuation

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Assessment and validation of liquid breakup models for high-pressure dense diesel sprays

Yi REN,Xianguo LI

《能源前沿（英文）》 2016年第10卷第2期页码 164-175 doi: 10.1007/s11708-016-0407-9

摘要： Liquid breakup in fuel spray and atomization significantly affects the consequent mixture formation, combustion behavior, and emission formation processes in a direct injection diesel engine. In this paper, different models for liquid breakup processes in high-pressure dense diesel sprays and its impact on multi-dimensional diesel engine simulation have been evaluated against experimental observations, along with the influence of the liquid breakup models and the sensitivity of model parameters on diesel sprays and diesel engine simulations. It is found that the modified Kelvin-Helmholtz (KH)–Rayleigh-Taylor (RT) breakup model gives the most reasonable predicted results in both engine simulation and high-pressure diesel spray simulation. For the standard KH-RT model, the model constant for the breakup length has a significant effect on the predictability of the model, and a fixed value of the constant cannot provide a satisfactory result for different operation conditions. The Taylor-analogy-breakup (TAB) based models and the RT model do not provide reasonable predictions for the characteristics of high-pressure sprays and simulated engine performance and emissions.

关键词： breakup model diesel engine high-pressure injection simulations

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表面驱动高压工艺 Perspective

Keith E. Gubbins, Kai Gu, Liangliang Huang, Yun Long, J. Matthew Mansell, Erik E. Santiso, Kaihang Shi, Małgorzata Ś liwińska-Bartkowiak, Deepti Srivastava

《工程（英文）》 2018年第4卷第3期页码 311-320 doi: 10.1016/j.eng.2018.05.004

摘要：

许多化学过程都要在高压下进行，因为高压状态能提高产率，加快化学反应的速率，分离过程中提高溶剂功率，并通过增加分子能量和分子碰撞率来克服活化作用的障碍。通过金刚石砧室压力能高达数百万巴，实验室就能达到这种效果，因此为利用热力学、输运和电子性质来进行化学合成以及合成新材料提供了新的途径。然而，在工业规模上，高压工艺目前正受到压缩成本和有限材料的约束，因此很少有工业过程能够在在压力超过25 MPa的情况下进行。本文提出了一种高压工艺的替代方法，即利用来自固体底物的表面驱动的相互作用产生非常高的局部压力。近期的实验和分子模拟表明，这种相互作用可以产生高达数万巴的局部压力，某些情况下甚至可以达到数百万巴。由于活跃的高压区域分布不均匀，压力在不同方向上存在差异。在许多情况下，增强最多的是平行于底物表面的压力（切向压力）。这种压力是施加在要加工的分子上的，而不是施加在固体底物或容器上。本文综述了现阶段对这种增压的认识，并讨论了一种基于表面驱动力的可行方法来达到高压处理的效果。这种表面驱动高压处理的优点在于，相比传统的整体相位处理，它能达到更高的压力，因为它不需要机械压缩。此外，过程中没有对容器施加更大的压力，因此不用担心材料受损。

关键词：限制高压高压相高压反应高压制造高压化学工艺

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Confining pressure effect on dynamic response of high rockfill dam

Xuexing CAO, Yunlong HE, Kun XIONG,

《结构与土木工程前沿（英文）》 2010年第4卷第1期页码 116-126 doi: 10.1007/s11709-010-0014-5

摘要： Studies show that the dynamic properties of rockfill are strongly dependent on the confining pressure. Therefore, confining pressure effect has become a very important factor in the seismic analysis of high rockfill dam. The relationships of dynamic shear modulus versus dynamic shear strain and damping ratio versus dynamic shear strain had been improved to a certain degree on the basic of widely used Hardin-Drnevich constitutive model in this paper. Then a new model that could consider confining pressure effect has been established. Regression analysis was carried out of the dynamic triaxial experimental data of the damming materials in the Changheba hydropower station of Sichun Province, China. The results show that, the new model can fit the test data well under various confining pressures. A corresponding computational procedure was compiled and applied in the dynamic response analysis of the Changheba Dam. Comparing the calculation results between the new constitutive model and the ordinary Hardin-Drnevich model, it can be seen that the result is conservative to some extent without considering confining pressure effect.

关键词： confining pressure effect high rockfill dam dynamic response Hardin-Drnevich constitutive model

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Terahertz time-domain spectroscopy of high-pressure flames

Jason BASSI, Mark STRINGER, Bob MILES, Yang ZHANG

《能源前沿（英文）》 2009年第3卷第2期页码 123-133 doi: 10.1007/s11708-009-0033-x

摘要： Laser spectroscopy in the visible and near infrared is widely used as a diagnostic tool for combustion devices, but this approach is difficult at high pressures within a sooty flame itself. High soot concentrations render flames opaque to visible light, but they remain transparent to far-infrared or terahertz (THz) radiation. The first far-infrared absorption spectra, to the best of our knowledge, of sooty, non-premixed, ethylene high-pressure flames covering the region of 0.2-2.5 THz is presented. A specially designed high-pressure burner which is optically accessible to THz radiation has been built allowing flame transmission measurements up to pressures of 1.6 MPa. Calculations of the theoretical combustion species absorption spectra in the 0.2-3 THz range have shown that almost all the observable features arise from H O. A few OH (1.84 and 2.51 THz), CH (2.58 THz), and NH (1.77 and 2.95 THz) absorption lines are also observable in principle. A large number of H O absorption lines are observed in the ground vibrational in a laminar non-premixed, sooty flame (ethylene) at pressures up to 1.6 MPa.

关键词： terahertz time-domain spectroscopy high-pressure flames H₂O absorption lines

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High pressure air spray assistant power supply control strategies and their effects on diesel engine

HAN Yongqiang, LIU Zhongchang, WANG Zhongshu, ZHU Ruoqun

《能源前沿（英文）》 2007年第1卷第3期页码 295-299 doi: 10.1007/s11708-007-0042-6

摘要： In order to reduce smoke from direct-injection (DI) turbo-charged and after-cooled (TCA) diesel engines under transient operations, the real-time controlling and measuring system of a high pressure air spray assistant power supply (HPAS) was developed. Effects of HPAS on a DI TCA diesel engine under constant engine speed and increased torque (CSIT) transient operations were studied by using different control strategies. Pre-spray (PS) strategy, which means supplying highly pressurized air into the exhaust manifold two seconds before the accelerating-graph begins to rise and stopping spraying air when the accelerating-graph stops rising. Two other strategies—full-time-spray (FTS) and middle-time-spray (MTS)—were used to fully exploit HPAS potential. With the FTS and MTS strategies, the HPAS system can remarkably decrease smoke from DI TCA diesel engines under transient operations.

关键词： different after-cooled real-time controlling CSIT supply

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未来飞机液压系统的特点

王占林,陈斌

《中国工程科学》 1999年第1卷第3期页码 5-10

摘要：

现代飞机舵面操纵系统与动力收放系统几乎都是液压驱动的。随着飞机特别是军用飞机的发展，对机载液压系统提出了更高的要求。文章对飞机特别是军用飞机液压系统的主要发展趋势进行了综述，并对国内外的飞机液压系统的研究工作进行了一定的介绍。指出：质量轻、体积小、高压化、大功率、变压力、智能化、集成化、余度技术等是未来飞机液压系统的主要发展趋势，尤其是高压变压力泵源系统对未来飞机的发展尤为重要。

关键词：机载液压系统高压化变压力余度功率电传

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Spray characteristics of high-pressure swirl injector fueled with alcohol

WANG Xibin, CHEN Wansheng, GAO Jian, JIANG Deming, HUANG Zuohua

《能源前沿（英文）》 2007年第1卷第1期页码 105-112 doi: 10.1007/s11708-007-0012-z

摘要： The spray characteristics of methanol and ethanol with high-pressure swirl injector were explored experimentally and numerically. Experimental results show that the spray characteristics of methanol and ethanol had displayed the same trends as that of gasoline. Under the low back-pressure ambient conditions, the spray behavior exhibited a hollow cone with wide spray angle and initial spray slug at the tip, while the spray presented a solid cone in the case of high back-pressure. Vortexes in the opposite direction existed in the rear part of the spray under low back-pressure ambient conditions while the vortexes formed in the middle part under high back-pressure ambient conditions. Experiments also showed that methanol had the largest cone angle, while ethanol and gasoline presented almost the same cone angle. Simulation results indicated that methanol and ethanol had a slightly larger Sauter mean diameter (SMD) than that of gasoline with swirl injector. The SMD profile of methanol coincided well with that of ethanol under low back-pressure ambient conditions, but displayed a slightly larger value under high back-pressure due to fuel evaporation. Numerical simulation could successfully demonstrate the spray characteristics of high-pressure swirl injector for methanol and ethanol fuels.

关键词： low back-pressure diameter initial spray hollow middle

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高压高产含硫气井测试技术及应用

王世泽,唐瑞江, 赵祚培,杜林

《中国工程科学》 2010年第12卷第10期页码 56-60

摘要：

川东北海相气藏埋藏深、温度压力高、普遍含硫、平面及纵向产量变化大，测试工艺复杂，面临井下工具受限、井下事故复杂、井控及环境污染风险大等难题。在川东北高含硫气井测试实践与经验基础上，形成了高压高产含硫气井测试技术。形成了三类六套APR射孔—酸压—测试联作短期测试管柱；管柱力学分析、多级压力控制、国产抗硫及复合地面流程等测试配套工艺满足各类测试要求；以压井、防喷、防漏为主的测试应急方案及措施确保了作业安全。该技术在YB1-侧1，YB12，HB1-1D等井中成功应用，为该类气田勘探开发的顺利进行提供了技术支撑。

关键词：高压高产含硫气藏测试

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大直径泥水盾构带压进仓地层加固及保压技术

孟海峰,苏清贵,翟志国

《中国工程科学》 2010年第12卷第12期页码 70-74

摘要：

通过对北京铁路地下直径线带压进仓换刀工程实例的分析，探讨了注浆加固及桩基加固在地层加固中的应用，分析了带压进仓的漏气原因并采取相应的应对措施，保证了盾构的正常施工。

关键词：盾构带压进仓保压注浆

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Wind tunnel test study on the wind pressure coefficient of claddings of high-rise buildings

Yong QUAN, Yi LIANG, Fei WANG, Ming GU

《结构与土木工程前沿（英文）》 2011年第5卷第4期页码 518-524 doi: 10.1007/s11709-011-0128-4

摘要： The area-averaged most unfavorable wind pressure coefficients (MUWPCs) on various regions of building surfaces and the influence of the side ratio and the terrain category were studied based on wind tunnel test data of scale models of typical high-rise buildings with rectangular cross-sections. The negative area-averaged MUWPCs in the middle-height edge areas generally increased with an increasing / side ratio. The area-averaged MUWPCs can be well fitted with a function of the average area reduced by the square of the building depth, . In addition, no unique pattern was found for the effect of the terrain category on the MUWPCs.

关键词： side ratio area-averaged pressure coefficients cladding terrain category

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Evaluation of the power consumption of a high-speed parallel robot

Gang HAN, Fugui XIE, Xin-Jun LIU

《机械工程前沿（英文）》 2018年第13卷第2期页码 167-178 doi: 10.1007/s11465-017-0456-8

摘要：

An inverse dynamic model of a high-speed parallel robot is established based on the virtual work principle. With this dynamic model, a new evaluation method is proposed to measure the power consumption of the robot during pick-and-place tasks. The power vector is extended in this method and used to represent the collinear velocity and acceleration of the moving platform. Afterward, several dynamic performance indices, which are homogenous and possess obvious physical meanings, are proposed. These indices can evaluate the power input and output transmissibility of the robot in a workspace. The distributions of the power input and output transmissibility of the high-speed parallel robot are derived with these indices and clearly illustrated in atlases. Furtherly, a low-power-consumption workspace is selected for the robot.

关键词： high-speed parallel robot dynamic model power consumption evaluation method power vector

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Improvement of engine performance with high compression ratio based on knock suppression using Millercycle with boost pressure and split injection

Haiqiao WEI, Jie YU, Lei ZHOU

《能源前沿（英文）》 2019年第13卷第4期页码 691-706 doi: 10.1007/s11708-019-0621-3

摘要： In theory, high compression ratio has the potential to improve the thermal efficiency and promote the power output of the SI engine. However, the application of high compression ratio is substantially limited by the knock in practical working process. The objective of this work is to comprehensively investigate the application of high compression ratio on a gasoline engine based on the Miller cycle with boost pressure and split injection. In this work, the specific optimum strategies for CR10 and CR12 were experimentally investigated respectively on a single cylinder DISI engine. It was found that a high level of Miller cycle with a higher boost pressure could be used in CR12 to achieve an effective compression ratio similar to CR10, which could eliminate the knock limits at a high compression ratio and high load. To verify the advantages of the high compression ratio, the fuel economy and power performance of CR10 and CR12 were compared at full and partial loads. The result revealed that, compared with CR10, a similar power performance and a reduced fuel consumption of CR12 at full load could be achieved by using the strong Miller cycle and split injection. At partial load, the conditions of CR12 had very superior fuel economy and power performance compared to those of CR10.

关键词： high compression ratio knock Miller cycle split injection engine performance

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标题作者时间类型操作

vapor deposition of excellent a-Si:H passivation layers for a-Si:H/c-Si heterojunction solar cells at highpressure and high power

Lei ZHAO,Wenbin ZHANG,Jingwei CHEN,Hongwei DIAO,Qi WANG,Wenjing WANG

期刊论文

Continuous deacylation of amides in a high-temperature and high-pressure microreactor

期刊论文

A novel high-temperature and high-pressure hydraulic pump based on mononeuron control

Linhui ZHAO, Xin FANG

期刊论文

Assessment and validation of liquid breakup models for high-pressure dense diesel sprays

Yi REN,Xianguo LI

期刊论文

表面驱动高压工艺

Keith E. Gubbins, Kai Gu, Liangliang Huang, Yun Long, J. Matthew Mansell, Erik E. Santiso, Kaihang Shi, Małgorzata Ś liwińska-Bartkowiak, Deepti Srivastava

期刊论文

Confining pressure effect on dynamic response of high rockfill dam

Xuexing CAO, Yunlong HE, Kun XIONG,

期刊论文

Terahertz time-domain spectroscopy of high-pressure flames

Jason BASSI, Mark STRINGER, Bob MILES, Yang ZHANG

期刊论文

High pressure air spray assistant power supply control strategies and their effects on diesel engine

HAN Yongqiang, LIU Zhongchang, WANG Zhongshu, ZHU Ruoqun

期刊论文

未来飞机液压系统的特点

王占林,陈斌