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The energy consumption in a batch stripper and a batch rectifier

Xianbao CUI, Tianyang FENG, Ying ZHANG, Zhicai YANG,

《化学科学与工程前沿(英文)》 2009年 第3卷 第4期   页码 443-452 doi: 10.1007/s11705-009-0266-6

摘要: The energy consumption in a batch rectifier and a batch stripper was investigated with a shortcut mathematical model. The minimum energy consumption of a batch stripper was compared to that of a batch rectifier under “general constant reflux” and “general constant distillate composition” with the ratio of minimum energy consumption /. When the feed contains a large amount of light component, the product purity specification is low and the relative volatility is small, the minimum energy consumption of a batch stripper is less than that of a batch rectifier under “general constant reflux” and “general constant distillate composition”. When the feed contains a small amount of light component, the product purity specification is very high and the relative volatility is low, a batch stripper can also consume less energy only in the “general constant distillate composition” operation mode. In other cases, a batch rectifier can consume less energy.

关键词: constant reflux     feed     energy consumption     general constant     product purity    

Research progress on low dielectric constant modification of cellulose insulating paper for power transformers

《化学科学与工程前沿(英文)》 2023年 第17卷 第8期   页码 991-1009 doi: 10.1007/s11705-022-2259-7

摘要: Because of the increase in the transmission voltage levels, the demand for insulation reliability of power transformers has increasingly become critical. Cellulose insulating paper is the main insulating component of power transformers. To improve the insulation level of ultrahigh voltage transformers and reduce their weight and size, reducing the dielectric constant of oil-immersed cellulose insulating paper is highly desired. Cellulose is used to produce power-transformer insulating papers owing to its excellent electrical properties, renewability, biodegradability and abundance. The dielectric constant of a cellulose insulating paper can be effectively reduced by chemical or physical modification. This study presents an overview of the foreign and domestic research status of the use of modification technology to reduce the dielectric constant of cellulose insulating papers. All the mentioned methods are analyzed in this study. Finally, some recommendations for future modified cellulose insulating paper research and applications are proposed. This paper can provide a reference for further research on low dielectric constant cellulose insulating paper in the future.

关键词: low dielectric constant     chemical and physical modification     cellulose insulating paper     transformer     nanomaterials.    

Analysis and characterization of wind-solar-constant torque spring hybridized model

Shantanu ACHARYA,Subhadeep BHATTACHARJEE

《能源前沿(英文)》 2014年 第8卷 第3期   页码 279-289 doi: 10.1007/s11708-014-0312-z

摘要: Solar and wind are the most promising renewable energy resources. But their unpredictable and varying nature prevents them from being used as the sole resource for power generation. This paper presents a model of wind and solar thermal hybrid power plant with a spring storage system which is expected to play an efficient role in combating with the drawbacks related to renewable power generation. In the proposed scheme, wind energy is harnessed by a hybrid vertical axis wind turbine, solar energy is utilized by a Stirling engine, and the surplus energy is stored in a winding spring. The paper discusses the working methodologies and analyses the performance of such 2.6 kW hybrid power plant model. It has been observed that the plant is capable of consistently generating 50% of its rated capacity irrespective of limitations in solar and wind resources.

关键词: hybrid vertical axis wind turbine     Stirling engine     solar-thermal energy     wind energy     constant torque spring    

Development of a fan-stirred constant volume combustion chamber and turbulence measurement with PIV

《能源前沿(英文)》 2022年 第16卷 第6期   页码 973-987 doi: 10.1007/s11708-021-0762-z

摘要: A fan-stirred combustion chamber is deve-loped for spherically expanding flames, with P and T up to 10 bar and 473 K, respectively. Turbulence characteristics are estimated using particle image velocimetry (PIV) at different initial pressures (P = 0.5–5 bar), fan frequencies (ω = 0–2000 r/min), and impeller diameters (D = 100 and 114 mm). The flame propagation of methanol/air is investigated at different turbulence intensities (u′=0–1.77 m/s) and equivalence ratios (φ = 0.7–1.5). The results show that u′ is independent of P and proportional to ω, which can be up to 3.5 m/s at 2000 r/min. LT is independent of P and performs a power regression with ω approximately. The turbulent field is homogeneous and isotropic in the central region of the chamber while the inertial subrange of spatial energy spectrum is more collapsed to –5/3 law at a high ReT. Compared to laminar expanding flames, the morpho-logy of turbulent expanding flames is wrinkled and the wrinkles will be finer with the growth of turbulence intensity, consistent with the decline of the Taylor scale and the Kolmogorov scale. The determined SL in the present study is in good agreement with that of previous literature. The SL and ST of methanol/air have a non-monotonic trend with φ while peak ST is shifted to the richer side compared to SL. This indicates that the newly built turbulent combustion chamber is reliable for further experimental study.

关键词: fan-stirred combustion chamber     turbulence characteristics     particle image velocimetry (PIV)     methanol     turbulent expanding flames    

A novel intravenous general anesthetic--- emulsified isoflurane: from bench to bedside

null

《医学前沿(英文)》 2012年 第6卷 第4期   页码 381-387 doi: 10.1007/s11684-012-0229-z

摘要:

Application of volatile anesthetics greatly alters modern medicine. There are obvious advantages of volatile anesthetics such as strong anesthetic potency, rapid onset and elimination through respiration system. Isoflurane is one of the most widely used volatile anesthetics in clinic. Emulsified isoflurane, the emulsion of isoflurane, is a novel intravenous general anesthetic. With the development of emulsified isoflurane in the past fifteen years, its utility has spread from intravenous general anesthesia to various fields including regional anesthesia, organ protection, as well as anesthetic pharmacological study. In this review, we will summarize literatures of emulsified isoflurane about its history, clinical application and future potential utility in the above mentioned fields.

关键词: emulsified isoflurane (EI)     general anesthesia     regional anesthesia     organ protection     anesthetic pharmacological study    

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    

coated on endotracheal tube with or without epidural lidocaine reduces isoflurane requirement during general

null

《医学前沿(英文)》 2012年 第6卷 第3期   页码 302-306 doi: 10.1007/s11684-012-0194-6

摘要:

This study was designed to evaluate the effect of tracheal topical anesthesia using EMLA? Cream (EC) coated on the endotracheal tube (ETT) with or without epidural anesthesia (EA) on isoflurane requirement during general anesthesia (GA) and investigate whether EC coated on the ETT with EA was associated with the additive effect compared with the effect when each anesthetic was administered independently. The prospective randomized, double-blinded, and controlled study included 60 ASA I–II patients scheduled for upper abdominal surgery requiring GA. Patients were randomly assigned to one of the following groups: group 1 received GA, group 2 received EC+ GA, group 3 received GA+ EA, and group 4 received EC+ GA+ EA. Isoflurane was administered at the required concentrations to maintain the mean arterial pressure at a level not exceeding 20% of preoperative values. The percentage mean expired concentration (%MEC) was used in calculating the isoflurane requirement. Emergence agitation, postoperative sore throat, and hoarseness were recorded. Groups 2, 3, and 4 exhibited a significant reduction on isoflurane requirement compared with group 1 (P<0.05). The isoflurane requirement evaluated by %MEC decreased by 12%, 38%, and 50% in groups 2, 3, and 4, respectively. The incidence of emergence agitation was significantly lower in groups 2 and 4 than those in groups 1 and 3 (P<0.05). Tracheal topical anesthesia using EC coated on ETT with or without EA reduced the isoflurane requirement during GA, indicating that EC combined with EA exhibited an additive effect on the requirement of general anesthetic.

关键词: EMLA? Cream     epidural anesthesia     general anesthesia     isoflurane     lidocaine    

The next step of community health construction: Training general practitioners and implementing health

Kan ZHANG MM, Wei DONG MM, Ying-Yao CHEN MD,

《医学前沿(英文)》 2010年 第4卷 第2期   页码 134-138 doi: 10.1007/s11684-010-0041-6

摘要: This article discusses the concept of health management and stresses that community health management should be the starting point of community health service, necessitating a paradigm shift from observing the treatment-oriented medical model to observing the prevention-and-health management-based medical model. Community health construction has entered a new phase, one which highlights the need to train general practitioners in practice-based life cycle health management. In addition, general practitioners should assume the mission of implementing community health management.

关键词: community health     general practitioners     health management    

Solar photovoltaic fed dual input LED lighting system with constant illumination control

Kinattingal SUNDARESWARAN,Kevin Ark KUMAR,Payyalore Raman VENKATESWARAN,Sankaran PALANI

《能源前沿(英文)》 2016年 第10卷 第4期   页码 473-478 doi: 10.1007/s11708-016-0420-z

摘要: A dual input LED lighting scheme with constant illumination is proposed in this paper. The scheme employs a photovoltaic array as the first input and a battery as the second one. A microcontroller is programmed to operate a changeover switch as well as a DC-DC converter for uninterrupted and constant illumination in work place. The scheme is suitable for conference halls, laboratories, clean rooms, marriage halls, theaters, etc. The complete modeling, design and experimentation of the proposed scheme are explained and the economic viability of the scheme is justified.

关键词: photovoltaic     LED light     dual input     P&O algorithm    

声学综合无损检测技术

陈积懋

《中国工程科学》 2000年 第2卷 第4期   页码 64-69

摘要:

论述了检测复合材料和胶接结构不连续(缺陷)的新型多模综合无损检测技术。该技术以声与超声检测技术为基础,包含五种不同检测模式,用以检测复合材料与胶接结构的失粘、脱粘、分层、疏松、夹芯压皱及其他缺陷。它适用于复合材料与构件的制造、维修和使用现场。它的适用对象范围广泛,几乎覆盖了现有常用的复合材料和胶接结构。它的检测可靠性高,重复精度好。文章还讨论了组成多膜声学综合胶接检测仪的五种不同检测模式的原理,并从我们和国内外同行的大量实践经验出发,说明了综合无损检测技术的巨大发展前景。

关键词: 声学综合检测     综合无损检测     复合材料无损检测     机械阻抗分析     振动分析     共振检测    

General modeling and optimization technique for real-world earth observation satellite scheduling

《工程管理前沿(英文)》   页码 695-709 doi: 10.1007/s42524-023-0263-3

摘要: Over the last two decades, many modeling and optimization techniques have been developed for earth observation satellite (EOS) scheduling problems, but few of them show good generality to be engineered in real-world applications. This study proposes a general modeling and optimization technique for common and real-world EOS scheduling cases; it includes a decoupled framework, a general modeling method, and an easy-to-use algorithm library. In this technique, a framework that decouples the modeling, constraints, and optimization of EOS scheduling problems is built. With this framework, the EOS scheduling problems are appropriately modeled in a general manner, where the executable opportunity, another format of the well-known visible time window per EOS operation, is viewed as a selectable resource to be optimized. On this basis, 10 types of optimization algorithms, such as Tabu search and genetic algorithm, and a parallel competitive memetic algorithm, are developed. For simplified EOS scheduling problems, the proposed technique shows better performance in applicability and effectiveness than the state-of-the-art algorithms. In addition, a complicatedly constrained real-world benchmark exampled by a four-EOS Chinese commercial constellation is provided, and the technique is qualified and outperforms the in-use scheduling system by more than 50%.

关键词: earth observation satellite     scheduling     general technique     optimization algorithm     commercial constellation     real-world     benchmark    

Feasible workspace regions for general two-revolute manipulator

Conghui LIANG, Marco CECCARELLI

《机械工程前沿(英文)》 2011年 第6卷 第4期   页码 397-408 doi: 10.1007/s11465-011-0228-9

摘要:

In this paper, a topology is presented for feasible workspace regions in general two-revolute manipulators. The design problem and concept of feasible workspace regions have been discussed as linked to each other. Design equations are formulated by arbitrarily prescribing four workspace boundary points. The so-called feasible workspace regions are the intersection of three different sub-regions, which are given by constraint curves as function of the relative positions of three workspace boundary points. By using a parametric study, all topologies for three sub-regions are figured out. Corresponding areas in cross section plane are determined for prescribing the position of a feasible workspace point as function of the topology for sub-regions. A classification has been proposed to determine and to characterize the combination of the topologies for those sub-regions. All topologies for feasible workspace regions are figured out and they are discussed as a design tool. Three general cases are analyzed in details to characterize workspace design capabilities for general two-revolute manipulators.

关键词: workspace     two-revolute manipulators     topology analysis     design    

General framework for bridge life cycle design

Junhai MA, Airong CHEN, Jun HE

《结构与土木工程前沿(英文)》 2009年 第3卷 第1期   页码 50-56 doi: 10.1007/s11709-009-0004-7

摘要: Based on a detailed illustration for bridge life cycle design which comprises the processes of service life design, aesthetics design, performance design, environmental and ecological design, inspection, maintenance and repair design as well as cost analysis, this paper presented a general framework for bridge life cycle design comprising three design phases and six design processes.

关键词: bridge whole life design     design phase     design process     general framework    

卫星移动网络总体概念设计仿真

金士尧

《中国工程科学》 2004年 第6卷 第1期   页码 30-36

摘要:

卫星移动网络是以卫星星座为基本物理架构,通过星际的通信链路形成覆盖全球的天基通信网络。它对社会发展、科技进步以及军队的信息化有着重大的推动作用。由于天网的移动性、通信的偶断性、接入的复杂性以及使用的综合性,都为研制提出了重大的挑战。有必要通过总体概念设计仿真,来进一步验证总体需求、总体方案、关键技术指标和研制的约束条件,形成科学的可行性报告。介绍了卫星移动网络的总体概念,设计了针对天网仿真的平台,并用实例获得卫星移动网络总体概念设计的仿真数据。

关键词: 卫星移动网络     总体     仿真    

用经典力学计算氢分子的键长键能及力常数

陈景

《中国工程科学》 2003年 第5卷 第6期   页码 39-43

摘要:

氢原子中1 s电子的电子云呈球形,电子的最大几率密度分布出现在玻尔半径a0的球壳内,认为几率密度分布及电子云属统计规律,意味着已经使用了宏观时标,这样就使氢分子体系中能量和时间的作用量远大于普郎克常数;根据电子云的交叠,用经典力学计算了基态氢分子的结构常数,获得键长、键能及力常数的表达式分别为Re = 〓a0,De = ze/4〓a0,k = ze/2〓,采用原子单位(a.u.)时z、e及a0均为1,获得Re=1.414 a.u.,De=0.177 a.u.,k=0.354 a.u.,这些数值与实验值的相对误差分别<1%,<2%和<4%;成键模型直观,物理意义明确,计算中不含任何人为性参数。

关键词: 氢分子     键长     键能     力常数    

标题 作者 时间 类型 操作

The energy consumption in a batch stripper and a batch rectifier

Xianbao CUI, Tianyang FENG, Ying ZHANG, Zhicai YANG,

期刊论文

Research progress on low dielectric constant modification of cellulose insulating paper for power transformers

期刊论文

Analysis and characterization of wind-solar-constant torque spring hybridized model

Shantanu ACHARYA,Subhadeep BHATTACHARJEE

期刊论文

Development of a fan-stirred constant volume combustion chamber and turbulence measurement with PIV

期刊论文

A novel intravenous general anesthetic--- emulsified isoflurane: from bench to bedside

null

期刊论文

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

Chung Nguyen VAN

期刊论文

coated on endotracheal tube with or without epidural lidocaine reduces isoflurane requirement during general

null

期刊论文

The next step of community health construction: Training general practitioners and implementing health

Kan ZHANG MM, Wei DONG MM, Ying-Yao CHEN MD,

期刊论文

Solar photovoltaic fed dual input LED lighting system with constant illumination control

Kinattingal SUNDARESWARAN,Kevin Ark KUMAR,Payyalore Raman VENKATESWARAN,Sankaran PALANI

期刊论文

声学综合无损检测技术

陈积懋

期刊论文

General modeling and optimization technique for real-world earth observation satellite scheduling

期刊论文

Feasible workspace regions for general two-revolute manipulator

Conghui LIANG, Marco CECCARELLI

期刊论文

General framework for bridge life cycle design

Junhai MA, Airong CHEN, Jun HE

期刊论文

卫星移动网络总体概念设计仿真

金士尧

期刊论文

用经典力学计算氢分子的键长键能及力常数

陈景

期刊论文