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2008—2017年河南省腹泻患者来源单相鼠伤寒沙门菌ST34的基因组流行病学特征研究 Article

穆玉娇, 李瑞超, 杜鹏程, 张沛, 李岩, 崔生辉, Séamus Fanning, 白莉

《工程（英文）》 2022年第15卷第8期页码 34-44 doi: 10.1016/j.eng.2022.05.006

摘要：本研究对2008-2017年分离自腹泻患者的100株序列型34型（ST34）S. 4,[5],12:i:-开展的流行情况、耐药表型和群体基因组学的分析发现：多数菌株对氨苄西林、链霉素、

关键词：单相鼠伤寒沙门菌 ST34 流行系统发育中国谱系

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Kinetic study of the methanol to olefin process on a SAPO-34 catalyst

Mehdi SEDIGHI,Kamyar KEYVANLOO

《化学科学与工程前沿（英文）》 2014年第8卷第3期页码 306-311 doi: 10.1007/s11705-014-1440-z

摘要： In this paper, a new kinetic model for methanol to olefin process over SAPO-34 catalyst was developed using elementary step level. The kinetic model fits well to the experimental data obtained in a fixed bed reactor. Using this kinetic model, the effect of the most important operating conditions such as temperature, pressure and methanol space-time on the product distribution has been examined. It is shown that the temperature ranges between 400 °C and 450 °C is appropriate for propene production while the medium temperature (450 °C) is favorable for total olefin yield which is equal to 33%. Increasing the reactor pressure decreases the ethylene yield, while medium pressure is favorable for the propylene yield. The result shows that the ethylene and propylene and consequently the yield of total olefins increase to approximately 35% with decreasing the molar ratio of inlet water to methanol.

关键词： methanol to olefin SAPO-34 kinetic modeling elementary step

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Clinical significance of CD34⁺CD117^dim/CD34⁺CD117^bri myeloblast-associated

Xueping Li, Yuting Dai, Bing Chen, Jinyan Huang, Saijuan Chen, Lu Jiang

《医学前沿（英文）》 2021年第15卷第4期页码 608-620 doi: 10.1007/s11684-021-0836-7

摘要： t(8;21)(q22;q22) acute myeloid leukemia (AML) is a highly heterogeneous hematological malignancy with a high relapse rate in China. Two leukemic myeloblast populations (CD34 CD117 and CD34 CD117 ) were previously identified in t(8;21) AML, and CD34 CD117 cell proportion was determined as an independent factor for this disease outcome. Here, we examined the impact of CD34 CD117 /CD34 CD117 myeloblast-associated gene expression on t(8;21) AML clinical prognosis. In this study, 85 patients with t(8;21) AML were enrolled. The mRNA expression levels of CD34 CD117 -associated genes ( , , and ) and CD34 CD117 -associated genes ( , , and ) were measured using quantitative reverse transcription PCR. Associations between gene expression and clinical outcomes were determined using Cox regression models. Results showed that patients with high , , or expression had significantly inferior overall survival (OS), whereas those with high or expression showed relatively favorable prognosis. Univariate analysis revealed that CD19, CD34 CD117 proportion, mutation, minimal residual disease (MRD), and expression levels of , , , and were associated with OS. Multivariate analysis indicated that mutation, MRD and and expression levels were independent prognostic variables for OS. Identifying the clinical relevance of CD34 CD117 /CD34 CD117 myeloblast-associated gene expression may provide new clinically prognostic markers for t(8;21) AML.

关键词： t(8 21)(q22 q22) AML CD34⁺CD117^dim/ CD34⁺CD117^bri cell population gene expression prognosis

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Promotional effect of ion-exchanged K on the low-temperature hydrothermal stability of Cu/SAPO-34 and

Chen Wang, Jun Wang, Jianqiang Wang, Meiqing Shen

《环境科学与工程前沿（英文）》 2021年第15卷第2期 doi: 10.1007/s11783-020-1322-1

摘要： Abstract • K+ hinder the structural degradation of Cu/SAPO-34 under humid condition<100°C. • K+ on Cu/SAPO-34 brings lower acidity and inferior SCR activity at high temperature. • Fe/Beta was used to compensate the low activity of Cu/SAPO-34 at high temperature. • The hybrid catalysts with KCu/SAPO-34 and Fe/Beta show a great potential for using. K ions were introduced onto Cu/SAPO-34 catalysts via the ion-exchange process in order to improve their stability under low-temperature hydrothermal aging. The changes in structure and copper-species contents of these catalysts upon hydrothermal aging were probed in order to investigate their effects on selective catalytic reduction (SCR) activity. For the fresh Cu/SAPO-34 catalysts, K ions had little influence on the chabazite framework but effected their acidities by exchanging with acid sites. After hydrothermal aging, the structural integrity and amount of active sites decreased on pure Cu/SAPO-34. While the K-loaded catalysts showed improved chabazite structure, acidity, and active site conservation with increasing K loading. However, although the 0.7 wt% K catalyst maintained the same crystallinity, active site abundance, and low-temperature SCR activity as the fresh catalyst upon aging, an apparent decrease in SCR activity at high temperature was observed because of the inevitable decrease in the number of Brönsted acid sites. To compensate for the activity disadvantage of K-loaded Cu/SAPO-34 at high temperature, Fe/Beta catalysts were co-employed with K-loaded Cu/SAPO-34, and a wide active temperature window of SCR activity was obtained. Thus, our study reveals that a combined system comprising Fe/Beta and K-loaded Cu/SAPO-34 catalysts shows promise for the elimination of NOx in real-world applications.

关键词： Selective catalytic reduction Cu/SAPO-34 catalyst Ion-exchanged K Low-temperature hydrothermal stability Fe/Beta catalyst

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Effect of temperature in the conversion of methanol to olefins (MTO) using an extruded SAPO-34 catalyst

Ignacio Jorge Castellanos-Beltran, Gnouyaro Palla Assima, Jean-Michel Lavoie

《化学科学与工程前沿（英文）》 2018年第12卷第2期页码 226-238 doi: 10.1007/s11705-018-1709-8

摘要： The methanol-to-olefin (MTO) reaction was investigated in a bench-scale, fixed-bed reactor using an extruded catalyst composed of a commercial SAPO-34 (65 weight percentage, wt-%) embedded in an amorphous SiO matrix (35 wt-%). The texture properties, acidity and crystal structure of the pure SAPO-34 and its extruded form (E-SAPO-34) were analyzed and results indicated that the extrusion step did not affect the properties of the catalyst. Subsequently, E-SAPO-34 was tested in a temperature range between 300 and 500 °C, using an aqueous methanol mixture (80 wt-% water content) fed at a weight hour space velocity (WHSV) of 1.21 h . At 300 °C, a low conversion was observed combined with catalyst deactivation, which was ascribed to oligomerization and condensation reactions. The coke analysis showed the presence of diamandoid hydrocarbons, which are known to be inactive molecules in the MTO process. At higher temperatures, a quasi-steady state was reached during a 6 h reaction where the optimal temperature was identified at 450 °C, which incidentally led to the lowest coke deposition combined with the highest H/C ratio. Above 450 °C, surges of ethylene and methane were associated to a combination of H-transfer and protolytic cracking reactions. Finally, the present work underscored the convenience of the extrusion technique for testing catalysts at simulated scale-up conditions.

关键词： MTO SAPO-34 temperature extrusion coke light alkanes

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High-precision diffusion measurement of ethane and propane over SAPO-34 zeolites for methanol-to-olefin

Dali Cai, Yu Cui, Zhao Jia, Yao Wang, Fei Wei

《化学科学与工程前沿（英文）》 2018年第12卷第1期页码 77-82 doi: 10.1007/s11705-017-1684-5

摘要： The methanol-to-olefin (MTO) process has attracted much attention and many problems including lifetime and selectivity of light olefins have all been connected to the diffusion problems in zeolite crystals. However, a quantitative study of diffusion problems in SAPO-34 zeolites is lacking. In this paper, we performed a high-precision diffusion measurement of the diffusion behavior of ethane and propane, which represent ethylene and propylene respectively, over SAPO-34. The diffusions of ethane and propane over fresh and coked SAPO-34 zeolites with different crystal sizes were carefully studied. Ethane and propane show different diffusion behavior in SAPO-34. The diffusion of ethane is almost not influenced by the crystal size and coke percentage, whereas that of propane is strongly affected. A slower diffusion velocity was observed in bigger crystals, and the diffusion velocity decline significantly with the coke percentage increasing. The diffusion coefficient was calculated with both the internal and surface diffusion models, and the results show that the surface diffusion plays a key role in the diffusion process of both ethane and propane. We believe that this work would be helpful for understanding the diffusion of different molecules in SAPO-34 zeolites, and may lay the foundation of MTO research.

关键词： diffusion measurement methanol-to-olefin process

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Silk Roads for the 21st Century: Engineering Mega-Infrastructure for Development and Sustainability

Tony Marjoram

《工程管理前沿（英文）》 2016年第3卷第3期页码 187-196 doi: 10.15302/J-FEM-2016038

摘要： Infrastructure facilitates the movement of people, the production and distribution of goods and services, and underpins development. Infrastructure is expensive and long-lasting, and needs long-term policy, planning and management, in terms of design, construction, operation and maintenance. Infrastructure relates particularly to engineering and technology. All technological change brings economic, social, cultural and environmental change, planned and unpredicted. Mega levels of technology bring mega levels of change, effects and impacts. Mega infrastructure such as the Silk Road Economic Belt and 21st Century Maritime Silk Road, the “One Belt, One Road” (OBOR) initiative, announced by President Xi Jinping in 2013, will require equally mega policy, planning and management. This paper will discuss policy, planning and management issues relating to mega infrastructure and the OBOR initiative, with particular reference to energy, communications, transportation, health, emergency preparedness and response, and less predictable areas of change, for example in disease prevention and control, within the overall need for economic, environmental and ecological sustainability. The paper will discuss associated needs for education, training and capacity building in engineering. The paper will also refer to lessons learnt from the original Silk Road in the context of the development of civilizations and intercultural dialogue through the transfer of goods, services, technologies, ideas, knowledge, customs, cultures and philosophies, less predictable and unwanted transfers, for example of disease, and the need for awareness, policy, planning and management of such wider issues.

关键词： infrastructure growth development sustainability change new Silk Roads

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Digital manufacturing—the development direction of the manufacturing technology in the 21st century

XIONG You-lun, YIN Zhou-ping

《机械工程前沿（英文）》 2006年第1卷第2期页码 125-130 doi: 10.1007/s11465-006-0021-3

摘要： After introducing the concepts of digital manufacturing technology, the discipline framework of digital manufacturing is presented in the paper by discussing its basic concept, theory foundation, key technology and scientific problems in detail. As the core of the advanced manufacturing technology, digital manufacturing is gradually becoming the main manufacturing technology of the twenty-first century. Firstly, the main features of digital manufacturing are indicated and its key supporting technologies are investigated by grouping them into four levels related to product development, numerical control, production management, and enterprise collaboration, respectively. Moreover, the existing problems in the research on the multi-discipline theory foundation of digital manufacturing such as manufacturing informatics, computational manufacturing, and manufacturing intelligence, are also indicated. Then, the core scientific problems of digital manufacturing are discussed in depth, which focuses on digitization of manufacturing information, modeling of manufacturing constraints, high-speed and high-precision numerical control theory, and Internet-based collaboration and integration. Lastly, the development trends and application perspectives of digital manufacturing are concluded.

关键词： development foundation multi-discipline scientific supporting

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Livestock breeding for the 21st century: the promise of the editing revolution

Chris PROUDFOOT, Gus MCFARLANE, Bruce WHITELAW, Simon LILLICO

《农业科学与工程前沿（英文）》 2020年第7卷第2期页码 129-135 doi: 10.15302/J-FASE-2019304

摘要：

In recent years there has been a veritable explosion in the use of genome editors to create site-specific changes, both and , to the genomes of a multitude of species for both basic research and biotechnology. Livestock, which form a vital component of most societies, are no exception. While selective breeding has been hugely successful at enhancing some production traits, the rate of progress is often slow and is limited to variants that exist within the breeding population. Genome editing provides the potential to move traits between breeds, in a single generation, with no impact on existing productivity or to develop phenotypes that tackle intractable issues such as disease. As such, genome editors provide huge potential for ongoing livestock development programs in light of increased demand and disease challenge. This review will highlight some of the more notable agricultural applications of this technology in livestock.

关键词： cattle pig sheep chicken aquaculture CRISPR

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Sustainable intensification of agriculture is key to feeding Africa in the 21st century

Shenggen FAN

《农业科学与工程前沿（英文）》 2020年第7卷第4期页码 366-370 doi: 10.15302/J-FASE-2020342

摘要：

Africa in facing numerous challenges in the 21st century in feeding its rapidly increasing population. Land resources have become limited due to urbanization and industrialization. The existing agricultural land has been degraded and soil fertility has declined due to unsustainable farming practices. Despite of progress made in the past several decades, hunger and malnutrition in Africa still hinder health, human development and economic growth, which will become even worse in the future if proper measures are not taken. Sustainable intensification is the only solution to tackling both environmental sustainability including climate change and malnutrition, i.e., to produce more foods in terms of nutrients human body needs with less natural resources and carbon emissions. To achieve this vision, innovations in technologies, policies and institutions are essential. The Chinese experience in Agricultural Green Development (AGD) can be shared with Africans when the region is pursuing its sustainable intensification strategy.

关键词： Africa sustainable intensification Agricultural Green Development climate change malnutrition

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21世纪油气工业发展刍议

陈俊武

《中国工程科学》 2000年第2卷第4期页码 21-24

摘要：

文章从世界能源消费不断增长的社会发展需求出发，考虑日益苛刻的环境保护政策和举世关心的可持续发展的战略方针，结合今后科学技术的进展，分别从产品需求和资源供应、产品规格和环境保护、非常规石油进入角色及天然气前景引人瞩目四个专题进行论述，对21世纪的以石油和天然气为代表的非再生能源工业形势做了初步展望。

关键词： 21世纪石油天然气油气工业

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An Algorithm to compute damage from load in composites

DUNANT, Stéphane P. A. BORDAS, Pierre KERFRIDEN, Karen L. SCRIVENER, Timon RABCZUK

《结构与土木工程前沿（英文）》 2011年第5卷第2期页码 180-193 doi: 10.1007/s11709-011-0107-9

摘要： We present a new method to model fracture of concrete based on energy minimisation. The concrete is considered on the mesoscale as composite consisting of cement paste, aggregates and micro pores. In this first step, the alkali-silica reaction is taken into account through damage mechanics though the process is more complex involving thermo-hygro-chemo-mechanical reaction. We use a non-local damage model that ensures the well-posedness of the boundary value problem (BVP). In contrast to existing methods, the interactions between degrees of freedom evolve with the damage evolutions. Numerical results are compared to analytical and experimental results and show good agreement.

关键词： Concrete damage prediction modelling energy minimisation ASR

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Self-motions of 3-RPS manipulators

HUSTY, Stéphane CARO, Philippe WENGERY

《机械工程前沿（英文）》 2013年第8卷第1期页码 62-69 doi: 10.1007/s11465-013-0366-3

摘要：

Recently a complete kinematic description of the 3-RPS parallel manipulator was obtained using algebraic constraint equations. It turned out that the workspace splits into two components describing two kinematically different operation modes. In this paper the algebraic description is used to give a complete analysis of all possible self-motions of this manipulator in both operation modes. Furthermore it is shown that a transition from one operation mode into the other in a self-motion is possible.

关键词： 3-RPS-manipulator singularity self-motion

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21世纪人类生活与生存的科技

蒋正华

《中国工程科学》 2002年第4卷第4期页码 1-11

摘要：

从管理学角度回顾了过去百年的世界历史，研究新世纪可能发生的进步，并探讨更好地建立世界和平与合作，实现共同发展的方案。

关键词： 21世纪科技进步人类生活与生存

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面向21世纪的中国林业遥感

赵宪文

《中国工程科学》 1999年第1卷第3期页码 16-21

摘要：

重点概述了近20年来林业遥感专家们为改进森林资源调查方法所作的诸多努力，如用卫星数据估计森林蓄积量、小块林地面积、以及森林郁闭度方法的研究、森林动态图的编制等。特别是上述方法在经过森林调查实际应用并进行效益分析后，提出的改进现行调查体系的建议。此外还提及了遥感用于评估、监测森林生态环境和森林灾害等方面取得的进展。对21世纪中国林业遥感前景进行了展望。作者认为下一个世纪中国林业遥感发展的主要方向是：包容各种新技术，形成新的技术体系，并与国际接轨；利用遥感的优势，研究森林的宏观状况与作用；与森林经营进一步结合。

关键词：林业遥感持续发展 21世纪