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超环面行星蜗杆传动研究综述

许立忠,杨育林,黄真

《中国工程科学》 2000年 第2卷 第6期   页码 84-88

摘要：

超环面行星蜗杆传动将滚动接触技术与行星蜗杆传动技术融为一体，是机械传动领域的前沿技术，具有承载能力大、传动效率高、传动比大和噪音小等优点。文章全面论述了该种传动的起源、研究现状及存在的问题，并提出未来应从啮合理论、制造技术和承载能力三个方面进一步开展研究工作，探索一套综合设计理论与制造技术，以实现超环面行星蜗杆传动设计与制造过程的合理化。

关键词： 超环面行星蜗杆传动     研究现状     存在问题     未来研究方向    

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IV) solvent extraction enhancement in high acidity using di-(2-ethylhexyl)phosphoric acid with [Cl] present: an experimental and theoretical study

《化学科学与工程前沿（英文）》 2023年 第17卷 第1期   页码 56-67 doi: 10.1007/s11705-022-2185-8

摘要： Separation of vanadium from black shale leaching solution at low pH is very meaningful, which can effectively avoid the generation of alkali neutralization slag and the resulting vanadium loss. In this study, coordination mechanism of vanadium in acid leaching solution at low pH was investigated with the intervention of chloride ions. Under the conditions of pH 0.8, di-(2-ethylhexyl)phosphoric acid concentration of 20%, phase ratio of 1:2, and extraction time of 8 min, the vanadium extraction could reach 80.00%. The Fourier transform infrared and electrospray ionization results reveal that, despite the fact that the chloride ion in the leachate could significantly promote vanadium extraction, the chloride ion does not enter the organic phase, indicating an intriguing phenomenon. Among Cl−–V, SO42−–V, and H2O–V, the V–Cl bond is longer and the potential difference between coordinate ions and vanadium is smaller. Therefore, VO2+ gets easily desorbed with chloride ions and enter the organic phase. At the same time, the hydrogen ions of di-(2-ethylhexyl)phosphoric acid also enter the water phase more easily, which reduces the pH required for the extraction reaction.

关键词： vanadium     black shale     solvent extraction     high acidity extraction    

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Renewable power for China: Past, present, and future

Eric MARTINOT

《能源前沿（英文）》 2010年 第4卷 第3期   页码 287-294 doi: 10.1007/s11708-010-0120-z

摘要： This paper briefly examines the history, status, policy situation, development issues, and prospects for key renewable power technologies in China. The country has become a global leader in wind turbine and solar photovoltaic (PV) production, and leads the world in total power capacity from renewable energy. Policy frameworks have matured and evolved since the landmark 2005 Renewable Energy Law, updated in 2009. China’s 2020 renewable energy target is similar to that of the EU. However, China continues to face many challenges in technology development, grid-integration, and policy frameworks. These include training, research and development, wind turbine operating experience and performance, transmission constraints, grid interconnection time lags, resource assessments, power grid integration on large scales, and continued policy development and adjustment. Wind and solar PV targets for 2020 will likely be satisfied early, although domestic demand for solar PV remains weak and the pathways toward incorporating distributed and building-integrated solar PV are uncertain. Prospects for biomass power are limited by resource constraints. Other technologies such as concentrating solar thermal power, ocean energy, and electricity storage require greater attention.

关键词： renewable energy     wind power     solar power     sustainable energy policy     green industry    

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The past, present and future of bovine pluripotent stem cells: a brief overview

Xiuchun TIAN

《农业科学与工程前沿（英文）》 2019年 第6卷 第1期   页码 3-7 doi: 10.15302/J-FASE-2018247

摘要：

Although the pursuit of bovine embryonic stem cells started more than 26 years ago for the purpose of gene-targeting, true pluripotent stem cells in this economically important species are still elusive. With the rapid advances in genome-editing and cloning using homologously recombined somatic cells, the need for pluripotent stem cells for precise genetic modification in any species became questionable. With the pig being the better model for human regenerative biology, the identification of the commonalities and uniqueness of the pluripotency circuitry across mammalian species may be the main objective for studying pluripotent stem cells in the bovine.

关键词： bovine     embryonic     induced     pluripotent stem cells    

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Laparoscopic hepato-biliary-pancreatic surgery: present practices and prospects

Yongjun Chen, Renyi Qin, Xiaoping Chen

《医学前沿（英文）》 2011年 第5卷 第3期   页码 235-238 doi: 10.1007/s11684-011-0156-4

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Effects of hydraulic retention time on net present value and performance in a membrane bioreactor treating

Dawei Yu, Jianxing Wang, Libin Zheng, Qianwen Sui, Hui Zhong, Meixue Cheng, Yuansong Wei

《环境科学与工程前沿（英文）》 2020年 第14卷 第6期 doi: 10.1007/s11783-020-1280-7

摘要： Abstract • The membrane bioreactor cost decreased by 38.2% by decreasing HRT from 72 h to 36 h. • Capital and operation costs contributed 62.1% and 37.9% to decreased costs. • The membrane bioreactor is 32.6% cheaper than the oxidation ditch for treatment. • The effluent COD also improved from 709.93±62.75 mg/L to 280±17.32 mg/L. • Further treatment also benefited from lower pretreatment investment. A cost sensitivity analysis was performed for an industrial membrane bioreactor to quantify the effects of hydraulic retention times and related operational parameters on cost. Different hydraulic retention times (72–24 h) were subjected to a flat-sheet membrane bioreactor updated from an existing 72 h oxidation ditch treating antibiotic production wastewater. Field experimental data from the membrane bioreactor, both full-scale (500 m3/d) and pilot (1.0 m3/d), were used to calculate the net present value (NPV), incorporating both capital expenditure (CAPEX) and operating expenditure. The results showed that the tank cost was estimated above membrane cost in the membrane bioreactor. The decreased hydraulic retention time from 72 to 36 h reduced the NPV by 38.2%, where capital expenditure contributed 24.2% more than operational expenditure. Tank construction cost was decisive in determining the net present value contributed 62.1% to the capital expenditure. The membrane bioreactor has the advantage of a longer lifespan flat-sheet membrane, while flux decline was tolerable. The antibiotics decreased to 1.87±0.33 mg/L in the MBR effluent. The upgrade to the membrane bioreactor also benefited further treatments by 10.1%–44.7% lower direct investment.

关键词： Antibiotic production wastewater     Net present value     Membrane bioreactor     Hydraulic retention time     Pollutant removal    

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Co-present Pb(II) accelerates the oxidation of organic contaminants by permanganate: Role of Pb(III)

《环境科学与工程前沿（英文）》 2022年 第16卷 第8期 doi: 10.1007/s11783-022-1530-y

摘要：

• Simultaneous removal of organic contaminants and Pb(II) was achieved by Mn(VII).

关键词： Permanganate     Pb(II) oxidation     MnO2     pH effect    

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Basic research on machinery fault diagnostics: Past, present, and future trends

Xuefeng CHEN, Shibin WANG, Baijie QIAO, Qiang CHEN

《机械工程前沿（英文）》 2018年 第13卷 第2期   页码 264-291 doi: 10.1007/s11465-018-0472-3

摘要：

Machinery fault diagnosis has progressed over the past decades with the evolution of machineries in terms of complexity and scale. High-value machineries require condition monitoring and fault diagnosis to guarantee their designed functions and performance throughout their lifetime. Research on machinery Fault diagnostics has grown rapidly in recent years. This paper attempts to summarize and review the recent R&D trends in the basic research field of machinery fault diagnosis in terms of four main aspects: Fault mechanism, sensor technique and signal acquisition, signal processing, and intelligent diagnostics. The review discusses the special contributions of Chinese scholars to machinery fault diagnostics. On the basis of the review of basic theory of machinery fault diagnosis and its practical applications in engineering, the paper concludes with a brief discussion on the future trends and challenges in machinery fault diagnosis.

关键词： fault diagnosis     fault mechanism     feature extraction     signal processing     intelligent diagnostics    

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Present situation and classification of piezoelectric pump

Fang YE, Shouyin WANG, Wei CHENG, Qixiao XIA, Jianhui ZHANG,

《机械工程前沿（英文）》 2009年 第4卷 第4期   页码 420-429 doi: 10.1007/s11465-009-0052-7

摘要： According to the present classification method for a piezoelectric pump, this paper reviews the development and present situation of piezoelectric pumps in the latest 30 years and finally puts forward a new classification. A volumetric piezoelectric pump, which belongs to traditional volumetric pumps, can be divided into a piezoelectric pump with or without valves. A new valveless piezoelectric pump nowadays becomes a hot issue in scientific research. It is constructed by using no-moving-part valves, which can induce positive flow resistance and negative flow resistance different, and in which the inlet and outlet are connected all the time. New forms of piezoelectric pumps, different from traditional ones, are only at the stage of conception and principle, and no practical application has been reported.

关键词： piezoelectric pump     development and present situation     new classification method     valveless piezoelectric pump     new forms of piezoelectric pump    

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中国低渗透油气的现状与未来

胡文瑞

《中国工程科学》 2009年 第11卷 第8期   页码 29-37

摘要：

中国低渗透油气资源丰富，具有很大的勘探开发潜力。近20年来，在低渗透砂岩、海相碳酸盐岩、火山岩勘探方面取得了很大发现，形成了国际一流的开发配套技术，实现了低渗透油气藏的规模有效开发，低渗透油气产量持续上升，其在产量构成中所占比例逐年增加。无论从近几年新增探明储量还是从剩余油气资源量看，低渗透油气都是今后勘探开发的主要对象，低渗透油气是中国未来油气工业的勘探开发主流，对保障国家能源安全具有重要的战略意义。

关键词： 低渗透     油气     勘探开发     主流     现状未来     技术    

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Major bridge development in Hong Kong, China—past, present and future

Michael CH HUI, Doris YAU

《结构与土木工程前沿（英文）》 2011年 第5卷 第4期   页码 405-414 doi: 10.1007/s11709-011-0136-4

摘要： The first “modern” type of vehicular bridge was built in Hong Kong China in the 1920s. The need for an efficient transportation system to cope with population growth and enable economic development has demanded the construction of more and more bridges since the middle of the 20th century. By 2007, Hong Kong had a total of about 1300 vehicular bridges. Four of these bridges, including the Tsing Ma Bridge, Kap Shui Mun Bridge, Ting Kau Bridge, and the cable-stayed bridge on the Hong Kong- Shenzhen Western Corridor, are considered to be major bridges supported by cables. Currently, the Stonecutters Bridge on Route No. 8 is under construction and is expected to be completed in late 2009. At the same time, the Hong Kong-Zhuhai-Macao Bridge will be in its detailed design stage soon. While efforts have been made by bridge builders to construct these giant structures, the upkeeping of these valuable assets at a high standard and ensuring their continuous functioning and performance during their intended lifespans will be another important task for bridge engineers. Wind and structural health monitoring system (WASHMS) will play a key role in this respect.

关键词： Tsing Ma Bridge     Kap Shui Mun Bridge     Ting Kau Bridge     Stonecutters Bridge     Hong Kong-Zhuhai-Macao Bridge     wind and structural health monitoring system (WASHMS)    

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大庆油田勘探技术现状及发展方向

冯志强,金成志,梁江平,赵波

《中国工程科学》 2010年 第12卷 第5期   页码 58-63

摘要：

针对大庆油田松辽盆地北部石油、松辽盆地北部深层天然气、复杂断陷盆地——海拉尔、依—舒地堑等外围油气的复杂目标勘探难题，开展了地震采集、处理、解释，测井及钻井等配套技术攻关，形成了岩性油藏高分辨率三维地震勘探技术、深层火山岩三维地震勘探技术、复杂断陷盆地三维地震勘探技术系列，低渗透储层、火山岩储层和复杂断陷储层评价及改造技术系列以及深层火山岩钻井技术，为松辽盆地北部岩性油藏的储量增长、深层火山岩天然气大型气藏发现和复杂断陷盆地勘探突破提供了技术支撑。

关键词： 大庆油田     勘探技术现状     发展方向    

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Three-dimensional reconstruction of light microscopy image sections: present and future

null

《医学前沿（英文）》 2015年 第9卷 第1期   页码 30-45 doi: 10.1007/s11684-014-0337-z

摘要：

Three-dimensional (3D) image reconstruction technologies can reveal previously hidden microstructures in human tissue. However, the lack of ideal, non-destructive cross-sectional imaging techniques is still a problem. Despite some drawbacks, histological sectioning remains one of the most powerful methods for accurate high-resolution representation of tissue structures. Computer technologies can produce 3D representations of interesting human tissue and organs that have been serial-sectioned, dyed or stained, imaged, and segmented for 3D visualization. 3D reconstruction also has great potential in the fields of tissue engineering and 3D printing. This article outlines the most common methods for 3D tissue section reconstruction. We describe the most important academic concepts in this field, and provide critical explanations and comparisons. We also note key steps in the reconstruction procedures, and highlight recent progress in the development of new reconstruction methods.

关键词： microtomy     3D imaging     computer-assisted image processing     3D printing     tissue scaffold    

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大菱鲆（Scophthalmus maximus L）养殖现状与可持续发展

雷霁霖,马爱军,陈超,庄志猛

《中国工程科学》 2005年 第7卷 第5期   页码 30-34

摘要：

大菱鲆（Scophthalmus maximus L）的良种优势地位已在我国确立，工厂化养殖的初级模式已经形成并获得普遍推广；规模化养殖和成鱼市场的不断扩大，将我国推进到世界大菱鲆养殖和消费大国行列；“大菱鲆效应”对我国海水工厂化养殖发展和沿海“三农”经济的拉动作用很大，也为我国海水工业化养殖奠定了理论和实践基础；当前由大菱鲆养殖产业的迅速发展而带来的机遇和挑战，正推动着我国海水工厂化养鱼朝良种化、规范化、国产化全封闭式的高级阶段攀登。

关键词： 大菱鲆     养殖现状     可持续发展    

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Growth responses of the newly-discovered Cd-hyperaccumulator Rorippa globosa and its accumulation characteristics of Cd and As under joint stress of Cd and As

SUN Yuebing, ZHOU Qixing, WEI Shuhe, REN Liping

《环境科学与工程前沿（英文）》 2007年 第1卷 第1期   页码 107-113 doi: 10.1007/s11783-007-0020-6

摘要： has been identified as a newly-found Cd-hyperaccumulating species. In the present study, growth responses of and its accumulation characteristics of Cd and As were examined under joint stress of Cd and As. The results showed that Cd and As had an antagonistic effect on enhancing the growth of plants and Cd uptake and accumulation under the low concentration Cd and As treatments. When the concentration of Cd in the soil was 10 mg/kg and the concentration of As was 50 mg/kg, the highest growing height of the plant was up to 35.9 cm and the dry weight of the shoots was up to 2.2 g/pot, respectively. Meanwhile, the accumulation of Cd in the leaves under the joint stress was higher than that at the same level under single Cd pollution. However, there were synergic adverse effects on plant growth and Cd uptake under the combined pollution from a high concentration of Cd and As. Meanwhile, the accumulation of As in the roots was greater than that in the shoots, the translocation factor (TF) was "d0.3 and the bioaccumulation factor (BF) was "d0.6, thus showing that had an excluding effect on As uptake. These results confirmed that had a strong tolerant ability to the joint stress of Cd and As, and the potential for phytoremediation of soils contaminated by Cd and As.

关键词： synergic adverse     stress     present study     potential     weight    

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标题 作者 时间 类型 操作

超环面行星蜗杆传动研究综述

许立忠,杨育林,黄真

期刊论文

IV) solvent extraction enhancement in high acidity using di-(2-ethylhexyl)phosphoric acid with [Cl] present: an experimental and theoretical study

期刊论文

Renewable power for China: Past, present, and future

Eric MARTINOT

期刊论文

The past, present and future of bovine pluripotent stem cells: a brief overview

Xiuchun TIAN

期刊论文

Laparoscopic hepato-biliary-pancreatic surgery: present practices and prospects

Yongjun Chen, Renyi Qin, Xiaoping Chen

期刊论文

Effects of hydraulic retention time on net present value and performance in a membrane bioreactor treating

Dawei Yu, Jianxing Wang, Libin Zheng, Qianwen Sui, Hui Zhong, Meixue Cheng, Yuansong Wei

期刊论文

Co-present Pb(II) accelerates the oxidation of organic contaminants by permanganate: Role of Pb(III)

期刊论文

Basic research on machinery fault diagnostics: Past, present, and future trends

Xuefeng CHEN, Shibin WANG, Baijie QIAO, Qiang CHEN

期刊论文

Present situation and classification of piezoelectric pump

Fang YE, Shouyin WANG, Wei CHENG, Qixiao XIA, Jianhui ZHANG,

期刊论文

中国低渗透油气的现状与未来

胡文瑞

期刊论文

Major bridge development in Hong Kong, China—past, present and future

Michael CH HUI, Doris YAU

期刊论文

大庆油田勘探技术现状及发展方向

冯志强,金成志,梁江平,赵波

期刊论文

Three-dimensional reconstruction of light microscopy image sections: present and future

null

期刊论文

大菱鲆（Scophthalmus maximus L）养殖现状与可持续发展

雷霁霖,马爱军,陈超,庄志猛

期刊论文

Growth responses of the newly-discovered Cd-hyperaccumulator Rorippa globosa and its accumulation characteristics of Cd and As under joint stress of Cd and As

SUN Yuebing, ZHOU Qixing, WEI Shuhe, REN Liping

期刊论文