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Cooling performance of grid-sheets for highly loaded ultra-supercritical steam turbines

Dieter BOHN , Robert KREWINKEL , Shuqing TIAN ,

《能源前沿（英文）》 2009年第3卷第3期页码 313-320 doi: 10.1007/s11708-009-0036-7

摘要： In order to increase efficiency and achieve a further CO-reduction, the next generation of power plant turbines will have steam turbine inlet temperatures that are considerably higher than the current ones. The high pressure steam turbine inlet temperature is expected to be increased up to approximately 700°C with a live steam pressure of 30MPa. The elevated steam parameters in the high and intermediate pressure turbines can be encountered with Ni-base alloys, but this is a costly alternative associated with many manufacturing difficulties. Collaborative research centre 561 “Thermally Highly Loaded, Porous and Cooled Multi-Layer Systems for Combined Cycle Power Plants” at RWTH Aachen University proposes cooling the highly loaded turbines instead, as this would necessitate the application of far less Ni-base alloys. To protect the thermally highly loaded components, a sandwich material consisting of two thin face sheets and a core made from a woven wire mesh is used to cover the walls of the steam turbine casing. The cooling steam is led through the woven wire mesh between the two face sheets to achieve a cooling effect. The wire mesh provides the grid-sheet with structural rigidity under varying operating conditions.In the present work, the cooling performance of the grid-sheets will be investigated applying the conjugate heat transfer method to ultra-supercritical live and cooling steam conditions for a section of the cooling structure. The behaviour of the flow and the heat transfer in the grid-sheet will be analyzed in detail using a parameter variation. The numerical results should give a first prediction of the cooling performance under future operating conditions.

关键词： steam turbines 700& deg C-technology numerical inverstigation cooling

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Additive manufacturing: technology, applications and research needs

Nannan GUO, Ming C. LEU

《机械工程前沿（英文）》 2013年第8卷第3期页码 215-243 doi: 10.1007/s11465-013-0248-8

摘要：

Additive manufacturing (AM) technology has been researched and developed for more than 20 years. Rather than removing materials, AM processes make three-dimensional parts directly from CAD models by adding materials layer by layer, offering the beneficial ability to build parts with geometric and material complexities that could not be produced by subtractive manufacturing processes. Through intensive research over the past two decades, significant progress has been made in the development and commercialization of new and innovative AM processes, as well as numerous practical applications in aerospace, automotive, biomedical, energy and other fields. This paper reviews the main processes, materials and applications of the current AM technology and presents future research needs for this technology.

关键词： additive manufacturing (AM) AM processes AM materials AM applications

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巨额资金将助推二氧化碳清除技术走向示范应用

Sarah C.P. Williams

《工程（英文）》 2023年第22卷第3期页码 7-9 doi: 10.1016/j.eng.2023.01.002

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对广电数字化运动的几点看法——兼谈对信息时代的数字技术标准化意义的反思

王天骏

《中国工程科学》 2004年第6卷第4期页码 9-14

摘要：

从信息革命的角度对于当前这场广电数字化运动做定位分析。对当前数字电视领域中的一些有争议的问题提出了看法。如，公共平台与收费平台的关系，服务平台的统一，整体平移，外来标准和自主标准，数字标准的统一等。提出了对标准化意义的反思。指出，在信息时代，给社会和技术带来进步的往往是追求标准化的过程，而不是标准建立的事实本身。近几年来，许多人已经开始意识到工业时代标准化的“旧瓶”，已经很难装下信息时代数字技术的“新酒”。标准化的工作要有一种新思维来适应信息社会的变化和特点。

关键词： CA 行业标准数字技术标准 DTV DVB-C ATSC ITU-T MPEG

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Valveless pumping using a two-stage impedance pump

C.-C. LEE, Y. A. ABAKR, K.-C. WOO

《机械工程前沿（英文）》 2013年第8卷第3期页码 311-318 doi: 10.1007/s11465-013-0270-x

摘要：

Impedance pump is defined as a type of valveless pumping mechanism, where an elastic tube is joined with a tube of different impedance, a periodic asymmetrical compression on part of the elastic tube will produce a unidirectional flow. Numerical and experimental studies had been conducted in the past, but little experimental work was found to exploit the principle of multi-stage impedance pumping for fluid transportation. This paper concentrates on the fluid behavior for an open-loop two-stage system experimentally. The aim of this work is to have an insight on the deliverable head and pumping rate of an open-loop two-stage impedance pumping system. This paper generally investigates the effect of different parameters towards the generation of unidirectional flows and composite flow of two opposite directions. Results obtained are of significant values.

关键词： valveless pumping open-loop two-stage unidirectional composite

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High-gravity intensified iron-carbon micro-electrolysis for degradation of dinitrotoluene

《化学科学与工程前沿（英文）》 2023年第17卷第10期页码 1595-1605 doi: 10.1007/s11705-022-2204-9

摘要： The application of iron–carbon (Fe–C) micro-electrolysis to wastewater treatment is limited by the passivation potential of the Fe–C packing. In order to address this problem, high-gravity intensified Fe–C micro-electrolysis was proposed in this study for degradation of dinitrotoluene wastewater in a rotating packed bed (RPB) using commercial Fe–C particles as the packing. The effects of reaction time, high-gravity factor, liquid flow rate and initial solution pH were investigated. The degradation intermediates were determined by gas chromatography-mass spectrometry, and the possible degradation pathways of nitro compounds by Fe–C micro-electrolysis in RPB were also proposed. It is found that under optimal conditions, the removal rate of nitro compounds reaches 68.4% at 100 min. The removal rate is maintained at approximately 68% after 4 cycles in RPB, but it is decreased substantially from 57.9% to 36.8% in a stirred tank reactor. This is because RPB can increase the specific surface area and the renewal of the liquid–solid interface, and as a result the degradation efficiency of Fe–C micro-electrolysis is improved and the active sites on the Fe–C surface can be regenerated for continuous use. In conclusion, high-gravity intensified Fe–C micro-electrolysis can weaken the passivation of Fe–C particles and extend their service life.

关键词： high-gravity technology rotating packed bed Fe–C micro-electrolysis dinitrotoluene wastewater active sites

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基于S3C2410的GPRS数据终端的设计

孙学用

《中国工程科学》 2007年第9卷第12期页码 94-96

摘要：提出了以S3C2410处理器为核心，以SIM100-E为GPRS通信模块,构建了一套嵌入式Internet数据终端的方案，对其硬件构成及工作流程进行了讨论，描述了其软件层次结构，并详细讲解了基于该平台的

关键词： GPRS；嵌入式Internet；S3C2410；SIM100-E

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Bioinspired C/TiO

Jian LI, Likun GAO, Wentao GAN

《农业科学与工程前沿（英文）》 2017年第4卷第4期页码 459-464 doi: 10.15302/J-FASE-2017178

摘要： butterfly wings were replicated by a sol-gel method and a calcination process, which could take advantage of the spatial features of the wing to enhance their photocatalytic properties. Hierarchical structures of -carbon-TiO (PP-C-TiO ) were confirmed by SEM observations. By applying the Brunauer-Emmett-Teller method, it was concluded that in the presence of wings the product shows higher surface area with respect to the pure TiO made in the absence of the wings. The higher specific surface area is also beneficial for the improvement of photocatalytic property. Furthermore, the conduction and valence bands of the PP-C-TiO are more negative than the corresponding bands of pure TiO , allowing the electrons to migrate from the valence band to the conduction band upon absorbing visible light. That is, the presence of C originating from wings in the PP-C-TiO could extend the photoresponsiveness to visible light. This strategy provides a simple method to fabricate a high-performance photocatalyst, which enables the simultaneous control of the morphology and carbon element doping.

关键词： bioinspired butterfly wings C/TiO₂ photocatalyst visible light

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Antithrombin deficiency and decreased protein C activity in a young man with venous thromboembolism:

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《医学前沿（英文）》 2018年第12卷第3期页码 319-323 doi: 10.1007/s11684-017-0553-4

摘要：

Antithrombin and protein C are two crucial members in the anticoagulant system and play important roles in hemostasis. Mutations in and lead to deficiency or dysfunction of the two proteins, which could result in venous thromboembolism (VTE). Here, we report a Chinese 22-year-old young man who developed recurrent and serious VTE in cerebral veins, visceral veins, and deep veins of the lower extremity. Laboratory tests and direct sequencing of and were conducted for the patient and his family members. Coagulation tests revealed that the patient presented type I antithrombin deficiency combined with decreased protein C activity resulting from a small insertion mutation c.848_849insGATGT in and a short deletion variant c.572_574delAGA in . This combination of the two mutations was absent in 400 healthy subjects each from southern and northern China. Then, we summarized all the mutations of the and gene reported in the Chinese Han population. This study demonstrates that the combination of antithrombin deficiency and decreased protein C activity can result in severe VTE and that the coexistence of different genetic factors may increase the risk of VTE.

关键词： antithrombin deficiency protein C activity mutation variant venous thromboembolism anticoagulants

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Atomistic simulations of plasma catalytic processes

Erik C. Neyts

《化学科学与工程前沿（英文）》 2018年第12卷第1期页码 145-154 doi: 10.1007/s11705-017-1674-7

摘要： There is currently a growing interest in the realisation and optimization of hybrid plasma/catalyst systems for a multitude of applications, ranging from nanotechnology to environmental chemistry. In spite of this interest, there is, however, a lack in fundamental understanding of the underlying processes in such systems. While a lot of experimental research is already being carried out to gain this understanding, only recently the first simulations have appeared in the literature. In this contribution, an overview is presented on atomic scale simulations of plasma catalytic processes as carried out in our group. In particular, this contribution focusses on plasma-assisted catalyzed carbon nanostructure growth, and plasma catalysis for greenhouse gas conversion. Attention is paid to what can routinely be done, and where challenges persist.

关键词： atomic scale simulation plasma-catalyst

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Elevated C-reactive protein levels predict worsening prognosis in Chinese patients with first-onset stroke

Jiangtao YAN, Rutai HUI, Daowen WANG

《医学前沿（英文）》 2009年第3卷第1期页码 30-35 doi: 10.1007/s11684-009-0005-x

摘要： The role of high sensitivity C-reactive protein (hsCRP) in predicting prognosis after stroke in the Asian population has not been investigated. We hypothesized that elevated levels of hsCRP were associated with worsening prognosis after stroke in Chinese patients. Two hundred and ninety consecutive patients with first-onset stroke and 290 age- and gender-matched control subjects without any cerebrovascular disease were enrolled for study. Plasma hsCRP level was detected and subsequent vascular events and death were recorded in both groups over a 5-year period. Compared to control group, patients presenting with stroke had higher plasma hsCRP level (3.3 ± 3.8 1.3 ± 2.2 mg/L, < 0.01). Furthermore, in the group of patients with stroke, the mean plasma hsCRP level was higher in patients who developed subsequent vascular diseases or died as compared with the patients without further complications (4.4 ± 4.3 2.7 ± 3.3 mg/L, < 0.01). Compared to the lowest tertile of hsCRP level, the relative risk for vascular events or death in stroke patients was 2.91 in the highest tertile of hsCRP (95% CI, 1.54–5.50, = 0.001). This increase in relative risk for vascular events or death in stroke patients continued after adjustment for age, sex and other cardiovascular risk factors such as hypertension and diabetes ( : 2.771, 95% CI: 1.367–5.617, = 0.005). These findings indicate that increased hsCRP level is associated with worsening prognosis after stroke in Chinese patients and suggests that inflammation is correlated with stroke outcome.

关键词： C-reactive protein inflammation stroke

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A simple, azulene-based colorimetric probe for the detection of nitrite in water

Lloyd C. Murfin, Carlos M. López-Alled, Adam C. Sedgwick, Jannis Wenk, Tony D. James, Simon E. Lewis

《化学科学与工程前沿（英文）》 2020年第14卷第1期页码 90-96 doi: 10.1007/s11705-019-1790-7

摘要： We describe the synthesis and evaluation of an azulene-based chemodosimeter for nitrite. The probe was found to undergo two distinct color changes upon introduction aqueous nitrite ion. A near-instant formation of a grey color provides a qualitative indication of the presence of nitrite, followed by the formation of a deep-yellow/orange color, the endpoint from which quantitative data can be derived. The azulene probe exhibits 1:1 stoichiometry of reaction with nitrite in water, and is selective for nitrite over other anions. The azulene probe was applied to determine nitrite content in cured meat, and compared with the British Standard testing procedure (Griess test). The value obtained from the azulene-based probe agreed closely with the standard test. Our procedure only requires the preparation of one standard solution, instead of the three required for the standard Griess test.

关键词： azulene nitrite diazoquinone