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Enrichment of CO from syngas with Cu(I)Y adsorbent by five-bed VPSA

Shuna LI, Huawei YANG, Donghui ZHANG

《化学科学与工程前沿（英文）》 2013年第7卷第4期页码 472-481 doi: 10.1007/s11705-013-1351-4

摘要： Cu(I)Y adsorbent was prepared by reduction of Cu(II)Y which was prepared by ion exchange between the NaY zeolite and a solution of Cu(II) chloride. The dynamic adsorption capacity of Cu(I)Y for CO was calculated by adsorption breakthrough curve measured on a fixed bed at 30°C and 0.006 MPa (g) of CO partial pressure. The calculated CO adsorption capacity was 2.14 mmol/g, 37.5 times as much as that of NaY zeolite. The adsorption breakthrough curve experiment was also simulated with Aspen Adsorption software and the results were approximately consistent with experimental results. Then a five-bed VPSA process for separating CO from syngas on this adsorbent was dynamically simulated with Aspen Adsorption software with the adsorption pressure of 0.68 MPa (g) and the desorption pressure of -0.075 MPa (g). The results showed that CO was enriched from 32.3% to 95.16%–98.12%, and its recovery was 88.47%–99.44%.

关键词： Cu(I)Y adsorbent breakthrough curve desorption VPSA simulation

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Is there an inverted U-shaped curve?Empirical analysis of the Environmental Kuznets Curve in agrochemicals

Fei LI,Suocheng DONG,Fujia LI,Libiao YANG

《环境科学与工程前沿（英文）》 2016年第10卷第2期页码 276-287 doi: 10.1007/s11783-014-0700-y

摘要： As the largest contributor to water impairment, agriculture-related pollution has attracted the attention of scientists as well as policy makers, and quantitative information is being sought to focus and advance the policy debate. This study applies the panel unit root, heterogeneous panel cointegration, and panel-based dynamic ordinary least squares to investigate the Environmental Kuznets Curve on environmental issues resulting from use of agricultural synthetic fertilizer, pesticide, and film for 31 provincial economies in mainland China from 1989 to 2009. The empirical results indicate a positive long-run co-integrated relationship between the environmental index and real GDP per capita. This relationship takes on the inverted U-shaped Environmental Kuznets Curve, and the value of the turning point is approximately 10,000–13,000, 85,000–89,000 and over 160,000 CNY, for synthetic fertilizer nitrogen indicator, fertilizer phosphorus indicator and pesticide indicator, respectively. At present, China is subject to tremendous environmental pressure and should assign more importance to special agriculture-related environmental issues.

关键词： Environmental Kuznets Curve agrochemical China

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Learning curve of totally thoracoscopic pulmonary segmentectomy

Weibing Wu, Jing Xu, Wei Wen, Yue Yu, Xinfeng Xu, Quan Zhu, Liang Chen

《医学前沿（英文）》 2018年第12卷第5期页码 586-592 doi: 10.1007/s11684-017-0566-z

摘要：

Totally thoracoscopic pulmonary segmentectomy (TTPS) is a feasible and safe technique that requires advanced thoracoscopic skills and knowledge of pulmonary anatomy. However, data describing the learning curve of TTPS have yet to be obtained. In this study, 128 patients who underwent TTPS between September 2010 and December 2013 were retrospectively analyzed to evaluate the learning curve and were divided chronologically into three phases, namely, ascending phase (A), plateau phase (B), and descending phase (C), through cumulative summation (CUSUM) for operative time (OT). Phases A, B, and C comprised 39, 33, and 56 cases, respectively. OT and blood loss decreased significantly from phases A to C (P <0.01), and the frequency of intraoperative bronchoscopy for target bronchus identification decreased gradually (A, 8/39; B, 4/33; C, 3/56; P = 0.06). No significant differences were observed in demographic factors, conversion, complications, hospital stay, and retrieved lymph nodes among the three phases. Surgical outcomes and techniques improved with experience and volume. CUSUM_OT indicated that the learning curve of TTPS should be more than 72 cases.

关键词： thoracoscopic segmentectomy learning curve CUSUM

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我国智能制造发展实践及突破路径研究

周勇,赵聃,刘志迎

《中国工程科学》 2022年第24卷第2期页码 48-55 doi: 10.15302/J-SSCAE-2022.02.025

摘要：

智能制造成为现代制造发展的必然趋势，既是“中国制造 2025”的主攻方向，也是我国制造业由大到强的必由之路。开展关于智能制造突破瓶颈的研究，对于推动制造业高质量发展、加快工业转型升级具有积极意义，也是践行“四个面向”的重要举措。本文系统梳理了我国智能制造发展实践，从智能制造战略布局、项目试点示范、产业集聚区分布、发展阶段研判等维度对其基本特征进行总结，深入剖析了发展过程中存在的问题。研究发现，现行的支持智能制造发展的部分标准、政策、技术、人才、财税等已不能适应新时期发展要求，在“十四五”时期，有必要从政策标准、核心技术、支撑要素等方面精准施策，以推动智能制造高质量发展。具体而言，应加强顶层设计，完善政策标准体系；强化战略布局，突破关键核心技术；健全制度保障，强化关键要素支撑。

关键词：智能制造政策标准核心技术支撑要素突破路径高质量发展

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SARS-CoV-2 variants, immune escape, and countermeasures

《医学前沿（英文）》 2022年第16卷第2期页码 196-207 doi: 10.1007/s11684-021-0906-x

摘要： Coronavirus disease 2019 (COVID-19) has become a global pandemic disease. SARS-CoV-2 variants have aroused great concern and are expected to continue spreading. Although many countries have promoted roll-out vaccination, the immune barrier has not yet been fully established, indicating that populations remain susceptible to infection. In this review, we summarize the literature on variants of concern and focus on the changes in their transmissibility, pathogenicity, and resistance to the immunity constructed by current vaccines. Furthermore, we analyzed relationships between variants and breakthrough infections, as well as the paradigm of new variants in countries with high vaccination rates. Terminating transmission, continuing to strengthen variant surveillance, and combining nonpharmaceutical intervention measures and vaccines are necessary to control these variants.

关键词： SARS-CoV-2 COVID-19 vaccine immune escape breakthrough prevention

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Numerical investigation of circle defining curve for two-dimensional problem with general boundaries

Chung Nguyen VAN

《结构与土木工程前沿（英文）》 2019年第13卷第1期页码 92-102 doi: 10.1007/s11709-018-0472-8

摘要： The scaled boundary finite element method (SBFEM) is applied to the static analysis of two dimensional elasticity problem, boundary value problems domain with the domain completely described by a circular defining curve. The scaled boundary finite element equations is formulated within a general framework integrating the influence of the distributed body force, general boundary conditions, and bounded and unbounded domain. This paper investigates the possibility of using exact geometry to form the exact description of the circular defining curve and the standard finite element shape function to approximate the defining curve. Three linear elasticity problems are presented to verify the proposed method with the analytical solution. Numerical examples show the accuracy and efficiency of the proposed method, and the performance is found to be better than using standard linear element for the approximation defining curve on the scaled boundary method.

关键词： exact geometry circular defining curve general boundaries SBFEM

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近六年《麻省理工科技评论》“全球十大突破性技术”解析与启示

屠海令,孙棕檀,姚源,徐源

《中国工程科学》 2017年第19卷第5期页码 85-91 doi: 10.15302/J-SSCAE-2017.05.015

摘要：

《麻省理工科技评论》自2001年起每年发布“全球十大突破性技术”，关注技术的商业应用潜力及其对人类生活和社会的重大影响。本文从技术影响类型、技术领域等角度入手，对《麻省理工科技评论》近六年发布的60项突破性技术进行深入理解和分析，为准确把握未来产业动态和科技趋势提供借鉴。

关键词：科技评论 “全球十大突破性技术” 商业产业社会

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学习曲线及在工业生产运作研究中的应用综述

陈志祥

《中国工程科学》 2007年第9卷第7期页码 82-88

摘要：

学习曲线是一种通过生产者行为学习与经验积累而得到改进的生产产出的特征函数，利用学习曲线可以科学地制定成本计划，改善作业计划、劳动定额与劳力规划，质量改善等。对国际上的研究文献、学习曲线的表现形式及其特点进行分析，探讨了几个新的应用动向。

关键词：学习曲线运作管理行为研究

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Research on physical shape preserving curve reconstruction

TANG Kelun, ZHANG Xiangwei, CHENG Siyuan, XIONG Hanwei, ZHANG Hong

《机械工程前沿（英文）》 2007年第2卷第3期页码 305-309 doi: 10.1007/s11465-007-0054-2

摘要： Fusion of various data is an effective way to improve the precision and efficiency of acquiring information in reverse engineering. A method of physical shape preserving curve reconstruction is proposed to better realize the data fusion of coordinate measuring machine (CMM) and visual information. From the principle of materials mechanics, the strain energy of the curve corresponding to the distortion is advanced as the internal energy, and the elastic potential energy of the curve is established, using a few precise measured data points as the equilibrium position, to be the external energy. On the basis of the principle of variation calculus, the basic spline finite element method (B-spline FEM) is used to determine the equilibrium position of curve deformation. Numerical simulation indicates that there is an extremely good agreement between the new fitted curve and the actual curve.

关键词： information CMM Numerical simulation effective coordinate measuring

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Interpolation of a spline developable surface between a curve and two rulings

Alicia CANTÓN,Leonardo FERNÁNDEZ-JAMBRINA

《信息与电子工程前沿（英文）》 2015年第16卷第3期页码 173-190 doi: 10.1631/FITEE.14a0210

摘要： In this paper we address the problem of interpolating a spline developable patch bounded by a given spline curve and the first and the last rulings of the developable surface. To complete the boundary of the patch, a second spline curve is to be given. Up to now this interpolation problem could be solved, but without the possibility of choosing both endpoints for the rulings. We circumvent such difficulty by resorting to degree elevation of the developable surface. This is useful for solving not only this problem, but also other problems dealing with triangular developable patches.

关键词： Developable surfaces Spline surfaces Blossoms

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Principle and curve of planetary indexing cam mechanisms

LIU Ming-tao, ZHANG Ce, YANG Yu-hu

《机械工程前沿（英文）》 2006年第1卷第4期页码 475-478 doi: 10.1007/s11465-006-0063-6

摘要： A new type of planetary indexing cam mechanism called type !c is presented. The transmission principle of type !c is discussed. Based on the principle of formation of conjugate tooth contour, the equations of the cam s pitch curve are derived. The continuity and symmetry of the cam s pitch curve are also analyzed. It can be concluded that: 1) This type has no output institution so the output precision can be improved; 2) The asymmetrical two-ring structure is used to overcome dead point and its phase angle is equal to (π - 2π/n); 3) The continuous condition of the cam s pitch curve is that the average transmission ratio is -n in an intermittent motion period.

关键词： continuity planetary average transmission symmetry intermittent

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The main achievements in the past 24 years and the prospects of mechanism research in China

ZOU Hui-jun, ZHANG Long, ZHANG Qing

《机械工程前沿（英文）》 2006年第1卷第3期页码 249-259 doi: 10.1007/s11465-006-0038-7

摘要： Since 1982, the symposiums on mechanism in China has been held fifteen times. In the past 24 years, Chinese mechanism has experienced a phenomenal development. Generally, fundamental research on traditional mechanisms is enhanced; mechanism and creative design of products are closely combined; modern mechanism with advanced and new technology is opened up; and mechanism is promoted to modernization. These are manifested in the following aspects: theory research on analysis and synthesis of traditional mechanism is deeply developed; computer-aided design on mechanisms is realized vigorously; conceptual design of mechanism system and mechanical products is energetically pushed; research on robot mechanisms and its industrial application is deeply developed; research on analysis and synthesis of controllable mechanisms and compliant mechanisms are energetically carried out; research on the dynamics of mechanisms and machines is vigorously developed; and reformation of teaching contents and system of mechanism is energetically carried out. Through the above-mentioned aspects of theory research and practical application, the theoretical and academic levels of Chinese mechanism can be considered at the advanced international level. However, there are not many original and breakthrough research achievements of fundamental research in China. In the meantime, there is a larger gap in the aspect of practical application of mechanism in the country compared with advanced countries in the world.

关键词： above-mentioned developed Generally reformation breakthrough research

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Detection of void and metallic inclusion in 2D piezoelectric cantilever beam using impedance measurements

S. SAMANTA, S. S. NANTHAKUMAR, R. K. ANNABATTULA, X. ZHUANG

《结构与土木工程前沿（英文）》 2019年第13卷第3期页码 542-556 doi: 10.1007/s11709-018-0496-0

摘要： The aim of current work is to improve the existing inverse methodology of void-detection based on a target impedance curve, leading to quick-prediction of the parameters of single circular void. In this work, mode-shape dependent shifting phenomenon of peaks of impedance curve with change in void location has been analyzed. A number of initial guesses followed by an iterative optimization algorithm based on univariate method has been used to solve the problem. In each iteration starting from each initial guess, the difference between the computationally obtained impedance curve and the target impedance curve has been reduced. This methodology has been extended to detect single circular metallic inclusion in 2D piezoelectric cantilever beam. A good accuracy level was observed for detection of flaw radius and flaw-location along beam-length, but not the precise location along beam-width.

关键词： piezoelectricity impedance curve mode shapes inverse problem flaw detection curve shifting

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交换式以太网NC建模与实时性能分析

王晓欣,刘鲁源,刘昆,马津艳

《中国工程科学》 2006年第8卷第6期页码 55-59

摘要：

交换式以太网的实时性能分析是工业以太网研究领域的一个热点课题，目前还没有一个有效的数学模型来对其进行描述。通过对典型交换机结构的分析，应用网络微积分理论建立了交换机的服务曲线模型，该模型将交换机中的数据流分为实时数据和非实时数据，并得到了最大延迟值和最大缓存需求值等，最大延迟为交换机的实时应用提供了理论边界值，最大缓存需求值为在实时工业环境中的交换机构建提供了理论参考。

关键词：网络微积分交换机到达曲线服务曲线延迟