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Self-propelled automatic chassis of Lunokhod-1: History of creation in episodes

Mikhail MALENKOV

《机械工程前沿（英文）》 2016年第11卷第1期页码 60-86 doi: 10.1007/s11465-016-0370-5

摘要：

This report reviews the most important episodes in the history of designing the self-propelled automatic chassis of the first mobile extraterrestrial vehicle in the world, Lunokhod-1. The review considers the issues in designing moon rovers, their essential features, and the particular construction properties of their systems, mechanisms, units, and assemblies. It presents the results of exploiting the chassis of Lunokhod-1 and Lunokhod-2. Analysis of the approaches utilized and engineering solutions reveals their value as well as the consequences of certain defects.

关键词： moon rover self-propelled chassis propulsion wheel suspension soil properties cross-country ability

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reduces IgE binding ability of allergenic egg white proteins

Sen LI, Marina OFFENGENDEN, Michael G. GÄNZLE, Jianping WU

《农业科学与工程前沿（英文）》 2018年第5卷第3期页码 373-381 doi: 10.15302/J-FASE-2018210

摘要：

Egg white proteins are one of the major allergens. The objective of this study was to investigate the effect of Aspergillus oryzae cultivation on IgE binding ability of egg white proteins. Effect of A. oryzae on egg white proteins was determined using ninhydrin method, SDS-PAGE, ELISA, fluorescence FITC labeling, MALDI-TOF-MS and LC-MS/MS analysis. Adding mycelium of A. oryzae ATCC 1011 and 16868 substantially reduced the IgE binding ability of acidified egg white after 24 h incubation. The binding capacity of egg white proteins to IgE in plasma from four egg allergy patients was almost completely lost after incubation with mycelium of ATCC 16868. Results from SDS-PAGE, free amino acid analysis, MALDI-TOF-MS and LC-MS/MS indicated that there was no substantial protein degradation during incubation. Therefore, the reduction of IgE binding ability of egg white proteins during A. oryzae treatment was probably due to a loss of ~1700 Da mass including a fragment of the ovomucoid N terminus.

关键词： Aspergillus oryzae egg allergy egg white proteins IgE-binding ability ovomucoid

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Filtration ability of hollow fiber membrane for production of magnesium ammonium phosphate crystals by

H. Watamura, H. Marukawa, I. Hirasawa

《化学科学与工程前沿（英文）》 2013年第7卷第1期页码 55-59 doi: 10.1007/s11705-013-1312-y

摘要： Relationship between magnesium ammonium phosphate (MAP) crystal properties and the filtration ability of hollow fiber membrane (HFM) were investigated. Phosphorus recovery process by crystallization has a problem that it produces a large amount of fine crystals. So improvement of the crystallization process by combining with filtration was discussed. MAP crystals were obtained by batch reaction crystallization and the filtration characteristics were investigated. The filtration was evaluated by the specific filtration resistance ( ) on HFM. Filtered slurry was prepared with each suspension density and crystal size distribution. The solution was filtered at constant pressure of 0.02 MPa and the filtration time on each filtrated volume was recorded. As a result, decreases exponentially with suspension density increasing from 0.25 g/L to 0.5 g/L and decreases moderately with suspension density increasing from 0.5 g/L to 1.5 g/L. of large crystals decreases exponentially at less suspension density than of small crystals does. Also, increases as the ratio of the fractured crystals increases.

关键词： membrane separation crystallization MAP

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一类弱非线性波浪数值模型及其适用性分析

刘忠波,唐军

《中国工程科学》 2010年第12卷第9期页码 96-100

摘要：

研究了一类含弱非线性的改进型Boussinesq水波方程，在非交错网格下，利用有限差分法建立了混合四阶Adams-Bashforth-Moulton的预报校正格式的波浪数值模型。在数值模型中，关于空间一阶导数差分格式采用四阶精度、二阶导数差分格式采用二阶精度。针对波浪的一维、二维传播变形问题进行了数值计算，并通过与相关实验结果对比分析考察了该数值模型的适用性。

关键词：数值模型适用性波浪

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Impact of introducing a herb pasture area into a New Zealand sheep and beef hill country farm system:

Cécile DURANTON, Cory MATTHEW

《农业科学与工程前沿（英文）》 2018年第5卷第1期页码 87-97 doi: 10.15302/J-FASE-2018202

摘要： New Zealand is well known for export of meat and dairy products from low cost pastoral systems. These farm systems are continually evolving for increased efficiency, in part through the use of metabolic energy modeling tools by farmers and farm consultants to explore alternative farm system configurations and identify new efficiencies. One recent innovation is the introduction of a herb pasture area, such as plantain. We used metabolic energy modeling to quantify seasonal feed flows in two successive years in a New Zealand hill country farm system, and to analyze the impact of the introduction of an area of plantain. Models employed were a self-built Microsoft Excel spreadsheet and a commercial New Zealand farm systems modeling package, FARMAX. Herbage production, animal performance and financial results for a base farm scenario created from the average of survey data for hill farms in the southern North Island, and the same farm with 10% and 20% of the area in plantain for the years 2010–2011 and 2011–2012 were modeled. The self-built model performed similarly to the commercial model. The system configuration of the base farm stockpiles surplus autumn feed for release to animals in winter and also incorporates flexibility that confers resilience to interannual weather variation through varying dates animals are purchased or sold. The introduction of an area of plantain was predicted to increase herbage production, animal performance and financial returns. The predicted benefit was higher for the year 2010–2011 where a drought occurred in summer than for the following year with higher summer rainfall. This demonstrates the profitability of introducing a plantain area to New Zealand hill farm systems, and suggests plantain will assist to mitigate adverse effects of warmer and drier summer conditions associated with current climate change trends.

关键词： farm system configuration herb pasture metabolic energy budgeting plantain sheep and beef farming

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优化输水方式提高三峡船闸通过能力措施研究

曹光荣,胡亚安,高雄

《中国工程科学》 2007年第9卷第12期页码 75-80

摘要：探讨了三峡船闸四级运行方式下二闸首作为首级运行时一闸室水体波动特性；阐述了波动形成的机理，分析了二闸首阀门运行方式对一闸室波动的影响；提出了满足一闸室待闸安全要求的阀门开启方式；通过实船试验检验了一闸室待闸船舶停泊条件，总结了一闸室待闸调度方式。运行实践表明，三峡船闸完建期实行四级运行方式下，将下行船舶由靠船墩移至一闸室满闸室待闸，可提高船闸日均通过闸次近3个，通航效益明显。

关键词：三峡船闸；输水方式；水流条件；通过能力

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3,4-ethylenedioxythiophene)-overoxidized polypyrrole composite films with enhanced electrocatalytic ability

《化学科学与工程前沿（英文）》 2023年第17卷第6期页码 735-748 doi: 10.1007/s11705-022-2262-z

摘要： In this study, a simple and effective method was proposed to improve the electrocatalytic ability of overoxidized poly(3,4-ethylenedioxythiophene)-overoxidized polypyrrole composite films modified on glassy carbon electrode for rutin and luteolin determination. The composite electrode was prepared by cyclic voltammetry copolymerization with LiClO₄-water as the supporting electrolyte. The peak current of rutin and luteolin on the composite electrode gradually decreased or even disappeared with the increase in the positive potential limit. After incubation in NaOH–ethanol solution with a volume ratio of 1:1, the composite electrodes prepared at positive potential limit greater than 1.5 V exhibited enhanced differential pulse voltammetry peak currents, reduced charge transfer resistance, larger effective specific surface area and higher electron transfer rate constant. The composite electrode prepared in the potential range of 0–1.7 V showed optimal electrocatalytic performance. The X-ray photoelectron spectroscopy results indicated that the content of –SO₂/–SO and –C=N– groups in the composite film increased significantly after incubation. Further, the Raman spectra and Fourier transform infrared spectra revealed that the thiophene ring structure changed from benzene-type to quinone-type, and the quinone-type pyrrole ring was formed. The electrocatalytic mechanism of the composite film was proposed based on the experimental results and further verified by Density Functional Theory calculation.

关键词： overoxidized poly(3 4-ethylenedioxythiophene)-overoxidized polypyrrole rutin luteolin incubation electrocatalytic mechanism

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Air pollution and its control in China

HAO Jiming, HE Kebin, DUAN Lei, LI Junhua, WANG Litao

《环境科学与工程前沿（英文）》 2007年第1卷第2期页码 129-142 doi: 10.1007/s11783-007-0024-2

摘要： The rapid growth of China s economy has led to severe air pollution characterized by acid rain, severe pollution in cities, and regional air pollution. High concentrations are found for various pollutants such as sulfur dioxides (SO), nitrogen oxides (NO), and fine particulates. Great efforts have thus been undertaken for the control of air pollution in the country. This paper discusses the development and application of appropriate technologies for reducing the major pollutants produced by coal and vehicles, and investigates air quality modeling as an important support for policy-making.

关键词： control development country regional important support

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Fabrication of titania thin film with composite nanostructure and its ability to photodegrade rhodamine

ZHANG Gaojie, WU Jinming, LIU Shaoguang, YAN Mi

《化学科学与工程前沿（英文）》 2008年第2卷第1期页码 44-48 doi: 10.1007/s11705-008-0001-8

摘要： A titania nanorod film was synthesized by direct oxidation of metallic Ti with hydrogen peroxide solution under a low temperature. Titania nanoparticles were then filled into the gaps among the nanorods through an infiltration sol-gel procedure to form a composite titania film with an ordered nanostructure. X-ray diffraction spectra indicate that the composite film was a mixture of anatase and rutile while the titania film obtained by only using a sol-gel procedure was pure anatase. Field emission scanning electron microscopy observations show that titania nanoparticles were embedded into the titania nanorod film. Photoluminescence spectra suggest the enhanced separation of electron and hole pairs for the obtained composite titania film over the corresponding titania nanorod film. The composite titania film exhibited improved ability to photodegrade rhodamine B in water compared with the titania nanorod film. The apparent photodegradation rate constant, fitting a pseudo-first-order, was 3 times of that obtained by the sol-gel derived titania film at the same weight. The improved photocatalytic activity for the composite titania film could be attributed to the enhanced separation of electron and hole pairs due to the embedding of the titania nanoparticles within the titania nanorods.

关键词： constant weight apparent photodegradation hydrogen nanorod

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Methods and applications of DEA cross-efficiency: Review and future perspectives

Jie WU, Jiasen SUN, Liang LIANG

《工程管理前沿（英文）》 2021年第8卷第2期页码 199-211 doi: 10.1007/s42524-020-0133-1

摘要： The field of engineering management usually involves evaluation issues, such as program selection, team performance evaluation, technology selection, and supplier evaluation. The traditional self-evaluation data envelopment analysis (DEA) method usually exaggerates the effects of several inputs or outputs of the evaluated decision-making unit (DMU), resulting in unrealistic results. To address this problem, scholars have proposed the cross-efficiency evaluation (CREE) method. Compared with the DEA method, CREE can rank DMUs more completely by using reasonable weights. With the extensive application of this technique, several problems, such as non-unique weights and non-Pareto optimal results, have arisen in CREE methods. Therefore, the improvement of CREE has attracted the attention of many scholars. This paper reviews the theory and applications of CREE, including the non-uniqueness problem, the aggregation of cross-efficiency data, and applications in engineering management. It also discusses the directions for future research on CREE.

关键词： cross-efficiency evaluation efficiency secondary goal model aggregation review

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Prevalence and determinations of physical inactivity among public hospital employees in Shanghai, China: a cross-sectional

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《医学前沿（英文）》 2015年第9卷第1期页码 100-107 doi: 10.1007/s11684-014-0372-9

摘要：

This study aims to explore the prevalence and determinations of physical inactivity among hospital employees in Shanghai, China. A cross-sectional study of 4612 employees aged 19 to 68 years was conducted through stratified cluster sampling from different classes of Shanghai hospitals in 2011. The total physical activity was evaluated using the metabolic equivalent according to the Global Physical Activity Questionnaire. Among the participants, 38.5%, 32.3%, and 64.6% of the employees are inactive at work, commuting, and taking leisure time, respectively. Up to 41.8% of the men and 37.8% of the women (P = 0.012) are physically inactive. When the age and educational level are adjusted, male doctors and medical technicians show a higher percentage of physical inactivity than male workers in logistics (P = 0.001). Among females, employees who are working in second- and third-class hospitals show a higher proportion of physical inactivity than those who are working in community health care centers. Logistic regression analyses show that the odds ratios (ORs) of leisure-time physical inactivity associated with the intensity of physical activity at work are 2.259, 2.897, and 4.266 for men (P<0.001) and 2.456, 3.259, and 3.587 for women (P<0.001), respectively. The time during commuting activities is significantly associated with leisure-time physical inactivity in either sex (OR= 2.116 for men and 2.173 for women, P<0.001). Hospital employees, particularly doctors and medical technicians, show a higher proportion of physical inactivity than other inhabitants in Shanghai. The time and intensity of activity at work and commuting are associated with leisure-time activities.

关键词： prevalence determination employee public hospital cross-sectional study physical inactivity

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River Chief System (RCS): An experiment on cross-sectoral coordination of watershed governance

Longfei Wang, Jiaxin Tong, Yi Li

《环境科学与工程前沿（英文）》 2019年第13卷第4期 doi: 10.1007/s11783-019-1157-9

摘要：

The trans-regional characteristics of watershed governance produce more problems beyond the capacity of each individual water-related department, leading to the fragmentation of watershed management. The River Chief System (RCS) has experienced swift developments over the past decade in China by appointing the local government heads as river chiefs. RCS works efficiently in the short-term due to its superiority in the inclusion of clear responsibility, authority, and multi-sectoral collaboration. However, the characteristics of the authority-based vertical coordination of the hierarchical system remain unchanged, and therefore the problems of organizational logic and the responsibility dilemma still exist. Tasks including perfecting of laws, integrated watershed management, and public participation still need to be completed. RCS reflects the routine and characteristics of the migration of national governance, and as such provides new insights for other developing countries in the design of river management systems.

关键词： River Chief System Watershed governance Cross-sectoral coordination Environmental protection

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基于微笑曲线理论的中国建筑业核心竞争力研究

叶娟,刘宏蛟

《中国工程科学》 2008年第10卷第12期页码 86-91

摘要：

建国以来，中国建筑业产值一直稳步提高，但低效率、低收益问题仍然没有得到解决。基于拓展服务领域、增加附加价值以提高我国建筑业核心竞争力的思路，从“广义的建筑业”和“广义的建设项目生命周期”出发，构建了建筑业的工程价值体系，并定义了相对附加经济价值这一概念。根据对目前我国建筑业现状的分析结果，研究了建设项目生命周期各个不同阶段附加价值的增值特点，做出了我国不同时期建筑业的微笑曲线，预测了我国建筑业未来的发展方向，最后探讨了提升我国建筑业核心竞争力的上、中、下游和整体发展战略。

关键词：建筑业核心竞争力微笑曲线相对附加经济价值全生命周期

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Air bearing center cross gap of neutron stress spectrometer sample table support system

Yang LI,Yunxin WU,Hai GONG,Xiaolei FENG

《机械工程前沿（英文）》 2016年第11卷第4期页码 403-411 doi: 10.1007/s11465-016-0405-y

摘要：

A support system is the main load-bearing component of sample table for neutron stress spectrometer, and air bearing is an important element of a support system. The neutron stress spectrometer sample table was introduced, and the scheme for air bearing combination was selected. To study the performance of air bearing center cross gap, finite element models (FEMs) were established based on air motion and Reynolds equations, effects of air supply pressure, and gap parameters on the overturning moment and bearing capacity of air bearing center cross gap were analyzed. Results indicate that the width, depth, and height differences of the marble floor gap played important roles in the performance of the air bearing. When gap width is lesser than 1 mm and gap depth is lower than 0.4 mm, bearing capacity and overturning moment would vary rapidly with the variation of the width and depth. A gap height difference results in the bearing capacity dropping rapidly. The FEM results agree well with experimental results. Further, findings of the study could guide the design of the support system and marble floor.

关键词： neutron stress spectrometer sample table support system air bearing center cross gap simulation experiment