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Effect of current density on groundwater arsenite removal performance using air cathode electrocoagulation

《环境科学与工程前沿（英文）》 2021年第15卷第6期 doi: 10.1007/s11783-021-1399-1

摘要：

• With the same charge, current density had little effect on As(III) removal in ACEC.

关键词： Electrocoagulation Air cathode Arsenic Current density Energy consumption

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EGG PRODUCTION IN CHINA: CURRENT STATUS AND OUTLOOK

Ning YANG

《农业科学与工程前沿（英文）》 2021年第8卷第1期页码 25-34 doi: 10.15302/J-FASE-2020363

摘要： Eggs are one of the most nutritious and affordable animal products worldwide. From 1985, egg production in China has retained the leading place in the world. A total of 33 Mt of eggs were produced in 2019 representing ˃ 40% of the world total production. Egg production in China is characterized by diversity in several aspects, including layer breeds, products and production systems. New breeds and synthetic lines are developed to improve the genetic potentials of egg production and feed efficiency of layers. In the past, layer farms were run mostly by small households with 100 to 1000 layers per farm. Over the past decades, egg production in China has developed toward standardization and expansion of production systems, and many of these modern intensive farms raise millions of layers. Although the Chinese egg products maintain strong competitiveness over other animal products and imported egg products, the egg industry will grow at a slower pace compared to the past. Chinese consumers are more concerned about the quality and safety of eggs and egg products, as well as the environmental issues related to animal production, which presents challenges for the Chinese egg industry.

关键词： poultry farms China diversity egg production trends

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基于迭代算法的有源电力滤波器谐波电流实时检测新方法

李自成,孙玉坤

《中国工程科学》 2006年第8卷第1期页码 46-50

摘要：

目前，已经提出了多种有源电力滤波器谐波及无功电流检测方法，尽管这些方法各有特点，但都存在着难以克服的问题，如计算量大，实时性差，检测精度不高等。文章在负载电流分析的基础上，提出了一种基于迭代算法的有源电力滤波器谐波电流实时检测方法，该方法具有计算量非常小，实时性好，检测精度高等特点。理论分析与仿真研究证实了该方法的正确性。

关键词：有源电力滤波器谐波电流有功电流无功电流

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EGG PRODUCTION IN CHINA: CURRENT STATUS AND OUTLOOK

《农业科学与工程前沿（英文）》 2021年第8卷第1期页码 25-34

摘要：

• China is now the largest egg production country worldwide

• Egg production in China is characterized by diversity in several aspects

• China is now capable of breeding new varieties, with more than 50% of the market share

• Policies have been implemented to ensure sustainable development of egg production

• Integrating crop-chicken-vegetable production system is established

Eggs are one of the most nutritious and affordable animal products worldwide. From 1985, egg production in China has retained the leading place in the world. A total of 33 Mt of eggs were produced in 2019 representing ˃ 40% of the world total production. Egg production in China is characterized by diversity in several aspects, including layer breeds, products and production systems. New breeds and synthetic lines are developed to improve the genetic potentials of egg production and feed efficiency of layers. In the past, layer farms were run mostly by small households with 100 to 1000 layers per farm. Over the past decades, egg production in China has developed toward standardization and expansion of production systems, and many of these modern intensive farms raise millions of layers. Although the Chinese egg products maintain strong competitiveness over other animal products and imported egg products, the egg industry will grow at a slower pace compared to the past. Chinese consumers are more concerned about the quality and safety of eggs and egg products, as well as the environmental issues related to animal production, which presents challenges for the Chinese egg industry.

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电力系统中对称和/或不对称故障的限流器阻抗优化新方法 None

Mahmoud MODARESI, Hamid LESANI

《信息与电子工程前沿（英文）》 2018年第19卷第2期页码 297-307 doi: 10.1631/FITEE.1601689

摘要：为给电力网络设计者选择故障限流器（fault current limiters，FCLs）的阻抗类型和阻值，提出一种基于其在网络中的位置计算最佳FCL阻值的新方法。

关键词：故障限流器（FCL）；FCL阻抗；短路电流；故障电流；电力系统

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Current situation and development of wind power in China

BAO Nengsheng, NI Weidou

《能源前沿（英文）》 2007年第1卷第4期页码 371-383 doi: 10.1007/s11708-007-0056-4

摘要： The current development of wind power in China was presented in this paper. Many regions such as Xinjiang Uygur Autonomous Region, Inner Mongolia Autonomous Region and southeast coastal region, etc. in China have abundant wind energ

关键词： Xinjiang current development Mongolia Autonomous southeast coastal Autonomous

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Circumcision of preschool boys in Baghdad, Iraq: prevalence, current practice and complications

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《医学前沿（英文）》 2013年第7卷第1期页码 122-125 doi: 10.1007/s11684-013-0242-x

摘要：

Circumcision is probably one of the most ancient surgical operations and has been performed more than any other operation. The aim of this study is to assess the prevalence of circumcision in preschool boys and to present an overview of the current practices and complications in Baghdad, Iraq. A statistical survey was conducted at the Central Teaching Hospital for Children in Baghdad, Iraq during the period April 2003 to October 2004. The survey consisted of structured interviews with the accompanying parents while waiting for their children’s routine appointments. A total of 4000 boys were included. 2 443 (61%) were circumcised and the prevalence of circumcision increased from 18% at 6 months of age to reach 92% at 6 years. Only 180 (7.4%) boys had a medical reason while the rest were circumcised for religious reasons. Parents were the only determinant in deciding the time and place of religious circumcision. Circumcision was performed by a doctor in 732 (30%) boys, by a nurse in 1276 (52%) and by a traditional circumciser in 435 (18%). Post-operative complications were encountered in 209 (8.5%) boys. Circumcision is an important surgical procedure that should be performed by trained medical staff in medical institutions. Circumcision performed by medical professionals caused significantly less complications.

关键词： circumcision children prevalence religious complications

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Numerical modeling of current-induced scour around multi-wall foundation using large-eddy simulation

《结构与土木工程前沿（英文）》 2023年第17卷第4期页码 546-565 doi: 10.1007/s11709-023-0943-4

摘要： Scouring is one of the primary triggers of failure for bridges across rivers or seas. However, research concerning the scour mechanism of multi-wall foundations (MWFs) remains scarce, hindering the further application of MWFs. In this study, for the first time, the scouring effect caused by unidirectional flow around MWFs was examined numerically using FLOW-3D involving a large-eddy simulation. Initially, the applicability of the scouring model and input parameters was validated using a case study based on published measured data. Subsequently, the scouring effects of four MWFs with different wall arrangements and inflow angles, including the flow field analysis and scour pit and depth, were investigated thoroughly. It was found that the maximum scour depth of MWFs with an inflow angle of 0° was smaller than that of those with an inflow angle of 45°, regardless of the wall arrangement. Meanwhile, changing the inflow angle significantly affects the scour characteristics of MWFs arranged in parallel. In practical engineering, MWFs arranged in parallel are preferred considering the need for scouring resistance. However, a comparative analysis should be performed to consider comprehensively whether to adopt the form of a round wall arrangement when the inflow angle is not 0° or the inflow direction is changeable.

关键词： multi-wall foundation current-induced scour bridge foundation large-eddy simulation numerical analysis

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Effect of counter current gas phase on liquid film

Shujuan LUO, Huaizhi LI, Weiyang FEI, Yundong WANG

《化学科学与工程前沿（英文）》 2009年第3卷第2期页码 135-137 doi: 10.1007/s11705-009-0129-1

摘要： Liquid film flow is very important in many industrial applications. However, there are few reports about its characteristics on structured packings. Therefore, in this paper, liquid film phenomena were investigated experimentally to exploit new approaches for intensifying the performance of the structured packings. All experiments were performed at room temperature. Water and air were the working fluids. The effect of counter current gas phase on the liquid film was taken into consideration. A high speed camera, a non-intrusive measurement technique, was used. It is shown that both liquid and gas phases have strong effects on film characteristics. In the present work, liquid film width increased by 57% because of increasing liquid flow rate, while it decreased by 25% resulting from the counter current gas phase.

关键词： counter current liquid film two phases structured packings

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Fault tolerant control strategy for modular PWM current source inverter

《能源前沿（英文）》 2023年第17卷第2期页码 228-238 doi: 10.1007/s11708-022-0852-6

摘要： In this paper, a fault-tolerant control method for an input-series output-parallel modular grid-tied pulse-width modulation (PWM) current source inverter is proposed to address the most commonly seen single symmetrical gate-commutated thyristor (SGCT) open-circuit fault problems. This method actively offsets the neutral point of the current space vector to ensure a sinusoidal output of the grid current, and it can achieve the upper limit power of the inverter under the condition of a single SGCT open-circuit fault. In addition, an active damping control method based on grid harmonic current feedback is proposed after analyzing the influence of the transformer ferromagnetic resonance caused by the neutral point offset on the power quality of the grid current. It has been demonstrated that the proposed method effectively suppresses the resonance caused by the transformer and the modified modulation, improving the grid current’s power quality.

关键词： current source converter (CSC) fault-tolerant control space vector modulation active damping resonance suppression power quality

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Catalysis of semihydrogenation of acetylene to ethylene: current trends, challenges, and outlook

《化学科学与工程前沿（英文）》 2022年第16卷第7期页码 1031-1059 doi: 10.1007/s11705-021-2113-3

摘要： Ethylene is an important feedstock for various industrial processes, particularly in the polymer industry. Unfortunately, during naphtha cracking to produce ethylene, there are instances of acetylene presence in the product stream, which poisons the Ziegler–Natta polymerization catalysts. Thus, appropriate process modification, optimization, and in particular, catalyst design are essential to ensure the production of highly pure ethylene that is suitable as a feedstock in polymerization reactions. Accordingly, carefully selected process parameters and the application of various catalyst systems have been optimized for this purpose. This review provides a holistic view of the recent reports on the selective hydrogenation of acetylene. Previously published reviews were limited to Pd catalysts. However, effective new metal and non-metal catalysts have been explored for selective acetylene hydrogenation. Updates on this recent progress and more comprehensive computational studies that are now available for the reaction are described herein. In addition to the favored Pd catalysts, other catalyst systems including mono, bimetallic, trimetallic, and ionic catalysts are presented. The specific role(s) that each process parameter plays to achieve high acetylene conversion and ethylene selectivity is discussed. Attempts have been made to elucidate the possible catalyst deactivation mechanisms involved in the reaction. Extensive reports suggest that acetylene adsorption occurs through an active single-site mechanism rather than via dual active sites. An increase in the reaction temperature affords high acetylene conversion and ethylene selectivity to obtain reactant streams free of ethylene. Conflicting findings to this trend have reported the presence of ethylene in the feed stream. This review will serve as a useful resource of condensed information for researchers in the field of acetylene-selective hydrogenation.

关键词： selectivity hydrogenation acetylene ethylene palladium

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Role of Akkermansia muciniphila in the development of nonalcoholic fatty liver disease: current knowledge

《医学前沿（英文）》 2022年第16卷第5期页码 667-685 doi: 10.1007/s11684-022-0960-z

摘要： Nonalcoholic fatty liver disease (NAFLD) is a hepatic manifestation of metabolic syndrome and a common cause of liver cirrhosis and cancer. Akkermansia muciniphila (A. muciniphila) is a next-generation probiotic that has been reported to improve metabolic disorders. Emerging evidence indicates the therapeutic potential of A. muciniphila for NAFLD, especially in the inflammatory stage, nonalcoholic steatohepatitis. Here, the current knowledge on the role of A. muciniphila in the progression of NAFLD was summarized. A. muciniphila abundancy is decreased in animals and humans with NAFLD. The recovery of A. muciniphila presented benefits in preventing hepatic fat accumulation and inflammation in NAFLD. The details of how microbes regulate hepatic immunity and lipid accumulation in NAFLD were further discussed. The modulation mechanisms by which A. muciniphila acts to improve hepatic inflammation are mainly attributed to the alleviation of inflammatory cytokines and LPS signals and the downregulation of microbiota-related innate immune cells (such as macrophages). This review provides insights into the roles of A. muciniphila in NAFLD, thereby providing a blueprint to facilitate clinical therapeutic applications.

关键词： Akkermansia muciniphila NAFLD NASH steatosis inflammation

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Eddy current measurement of the thickness of top Cu film of the multilayer interconnects in the integrated

Zilian QU,Yonggang MENG,Qian ZHAO

《机械工程前沿（英文）》 2015年第10卷第1期页码 1-6 doi: 10.1007/s11465-015-0325-2

摘要：

This paper proposes a new eddy current method, named equivalent unit method (EUM), for the thickness measurement of the top copper film of multilayer interconnects in the chemical mechanical polishing (CMP) process, which is an important step in the integrated circuit (IC) manufacturing. The influence of the underneath circuit layers on the eddy current is modeled and treated as an equivalent film thickness. By subtracting this equivalent film component, the accuracy of the thickness measurement of the top copper layer with an eddy current sensor is improved and the absolute error is 3 nm for sampler measurement.

关键词： CMP eddy current multilayer wafer Cu interconnects equivalent unit

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Assessment of robustness of structures: Current state of research

Colin BRETT, Yong LU

《结构与土木工程前沿（英文）》 2013年第7卷第4期页码 356-368 doi: 10.1007/s11709-013-0220-z

摘要： The concept of structural robustness and relevant design guidelines have been in existence in the progressive collapse literature since the 1970s following the partial collapse of the Ronan Point apartment building; however, in the more general context, research on the evaluation and enhancement of structural robustness is still relatively limited. This paper is aimed to provide a general overview of the current state of research concerning structural robustness. The focus is placed on the quantification and the associated evaluation methodologies, rather than specific measures to ensure prescriptive robustness requirements. Some associated concepts, such as redundancy and vulnerability, will be discussed and interpreted in the general context of robustness such that the corresponding methodologies can be compared quantitatively using a comparable scale. A framework methodology proposed by the authors is also introduced in line with the discussion of the literature.

关键词： structural robustness abnormal exposure vulnerability collapse consequence

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Series transformer based diode-bridge-type solid state fault current limiter

Amir HEIDARY,Hamid RADMANESH,Seyed Hamid FATHI,G. B. GHAREHPETIAN

《信息与电子工程前沿（英文）》 2015年第16卷第9期页码 769-784 doi: 10.1631/FITEE.1400428

摘要： We propose a novel series transformer based diode-bridge-type solid state fault current limiter (SSFCL). To control the fault current, a series RLC branch is connected to the secondary side of an isolation series transformer. Based on this RLC branch, two current limiting modes are created. In the first mode, R and C are bypassed via a paralleled power electronic switch (insulated-gate bipolar transistor, IGBT) and L remains connected to the secondary side of the transformer as a DC reactor. In the second mode, the series reactor impedance is not enough to limit the fault current. In this case, the fault current can be controlled by selecting a proper on-off duration of the parallel IGBT, across the series damping resistor ( ) and capacitor, which inserts high impedance into the line to limit the fault current. Then, by controlling the magnitude of the DC reactor current, the fault current is reduced and the voltage of the point of common coupling (PCC) is kept at an acceptable level. In addition, in the new SSFCL, the series RC branch, connected in parallel with the IGBT, serves as a snubber circuit for decreasing the transient recovery voltage (TRV) of the IGBT during on-off states. Therefore, the power quality indices can be improved. The measurement results of a built prototype are presented to support the simulation and theoretical studies. The proposed SSFCL can limit the fault current without any delay and successfully smooth the fault current waveform.

关键词： Solid state fault current limiter (SSFCL) Power quality Voltage sag Point of common coupling (PCC) Isolation transformer