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Journal of Semiconductors 2012年第3期33卷 87-93页

作者：李娅妮杨银堂朱樟明强玮 institute of Microelectronics Xidian University Xi'an Longtium Microelectronics Technology developing Co. Ltd

For low-power low total harmonic distortion（THD）,based on the CSMC 0.5μm BCD process,a novel boost power factor correction（PFC） converter in critical conduction mode is discussed and *** compensation design is introduced in order to increase the PWM duty cycle and supply more conversion energy near the input voltage zero-crossing points,thus regulating the inductor current of the PFC converter and compensating the system loop gain change with ac line *** theoretical and practical results reveal that the proposed PFC converter with feedforward compensation cell has better power factor and THD performance,and is suitable for low-power low THD design *** experimental THD of the boost PFC converter is 4.5%,the start-up current is 54μA,the stable operating current is 3.85 mA,the power factor is 0.998 and the efficiency is 95.2%.

关键词： CRM boost PFC low-power THD feedforward compensation

Spatial Spillovers from Foreign Direct Investment： Evidence from the Yangtze River Delta in China

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China & World Economy 2015年第2期23卷 40-60页

作者： Kiyoyasu Tanaka Yoshihiro Hashiguchi Inter-Disciplinary Studies Center Institute of Developing Economies Chiba Japan Development Studies Center Institute of Developing Economies Chiba Japan

This paper examines the spatial externality from foreign direct investment on domestic firms. Using Chinese firm-level data for 2004, and after accounting for an endogeneity problem, we find that foreign firms generate a significantly positive spillover effect on the regional productivity of domestic firms in similar counties and industries. Estimating a spatial-autoregressive model, we further show that such local spillovers could transmit to domestic firms in other counties and industries through interactions among domestic firms. However, these spatial multiplier effects decline with distance, thereby reducing the foreign direct investment spillover effects for domestic firms in distant locations.

关键词： China foreign direct investment productivity spatial spillovers

Hydraulic characteristics of an anaerobic baffled reactor as onsite wastewater treatment system

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Journal of Environmental Sciences 2010年第9期22卷 1319-1326页

作者： Yuttachai Sarathai Thammarat Koottatep Antoine Morel School of Environment Resources and Development Asian Institute of Technology Eawag:Swiss Federal institute for Aquatic Science & Technology Department for Water and Sanitation in Developing Countries(Sandec)

The feasibility of using anaerobic baffled reactor （ABR） as onsite wastewater treatment system was discussed. The ABR consisted of one sedimentation chamber and three up-flow chambers in series was experimented under different peak flow factors （PFF of 1 to 6）, superficial gas velocities （between 0.6 and 3.1 cm/hr） and hydraulic retention times （HRT）（24, 36 and 48 hr）. Residence time distribution （RTD） analyses were carded out to investigate the hydraulic characteristics of the ABR. It was found that the PFF resulted in hydraulic dead space. The dead space did not exceed 13% at PFF of 1, 2 and 4 while there was 2-fold increase （26%） at PFF of 6. Superficial gas velocities did not result in more （biological） dead space. The mixing pattern of ABR tended to be a completely- mixed reactor when PFF increased. Superficial gas velocities did not affect mixing pattern. The effects of PFF on mixing pattern could be minimized by higher HRT （48 hr）. The tank-in-series （TIS） model （N = 4） was suitable to describe the hydraulic behaviour of the studied system. The HRT of 48 hr was able to maintain the mixing pattern under different flow patterns, introducing satisfactory hydraulic efficiency. Chemical oxygen demand （COD） and total suspended solids （TSS） removals under all flow patterns were achieved more than 85% and 90%, respectively. The standard deviation of effluent COD and TSS concentration did not exceed 15 mg/L.

关键词： anaerobic baffled reactor dead space hydraulic characteristics onsite system peak flow factor

A Distributed DBMS Based Dynamic Programming Method for Query Optimization

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Journal of Donghua University(English Edition) 2012年第1期29卷 55-58页

作者：孙纪舟李阳蒋志勇顾云苏何清法 Beijing institute of Information and Control The Software developing Center of China Aerospace Science and Technology Corporation

Dynamic programming(DP) is an effective query optimization approach to select an appropriate join order for relational database management system(RDBMS) in multi-table joins. This method was extended and made available in distributed DBMS(D-DBMS). The structure of this optimal solution was firstly characterized according to the distributing status of tables and data, and then the recurrence relations between a problem and its sub-problems were recursively defined. DP in D-DBMS has the same time-complexity with that in centralized DBMS, while it has the capability to solve a much more sophisticated optimal problem of multi-table join in D-DBMS. The effectiveness of this optimal strategy has been proved by experiments.

关键词： distributed database dynamic programming (DP) multitable loin: auery optimization

Does Foreign Direct Investment Affect the Growth of Local Firms? The Case of China's Electrical and Electronics Industry

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China & World Economy 2012年第2期20卷 98-120页

作者： Koichiro Kimura Research Fellow Institute of Developing Economies(IDE)ChibaJapan.

Does foreign direct investment （FDI） into developing countries affect the growth of local firms in host countries？ Using a dataset of 38 sectors in China ＇s electrical and electronics industry, in this paper, we analyze whether FDI has a positive effect on loeal firms, with technology spillovers, added value and increasing total faetor productivity, or a negative, market stealing, effect. Estimating the relationship between growth of local firms and investment offoreign firms, our results show that FDI is likely to have a negative impact on the growth of local firms in sectors with large disparities in technology and less experience in business. Therefore, local firms lacking in technology need to find markets with no competition from foreign firms or determine strategies to compensate technology disparities.

关键词： China electrical and electronics industry foreign direct investment technology disparity technology spillover total factor productivity

General Properties of Low-frequency Power Losses in Fe-based Nanocrystalline Soft Magnetic Alloys

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Journal of Materials Science & Technology 2000年第1期16卷 37-44页

作者： Yanzhong ZHANG, Huijuan JIN and Ying SHI (Shanghai Key Laboratory for Research and developing and Applications of Metallic Function Materials, Research Center, Shanghai Iron and Steel Research institute,Shanghai 200940, China) Shanghai Key Lab. for Research and developing and Applications of Metallic Function Materials Research Center Shanghai Iron and Steel Research Institute Shanghai 200940 China

The dependences of the power loss per cycle on frequency f and amplitude flux density Bm have been investigated for the three main original magnetic states in five sorts of Fe-based nanocrystalline soft magnetic alloys in the ranges of 10 Hz<=f<=1000 Hz and 0.4 T<= Bm <=1.0 T. The total loss P is decomposed into the sum of the hysteresis loss Physt, the classical eddy current loss Pel and the excess loss Pexc. Physt has been found to be proportional to Bm^2 and f. The behavior of Pexc/f vs f being equivalent to P/f vs f clearly exhibits nonlinearity in the range not more than about 120 Hz, whereas the behavior of P/f vs f roughly shows linearity in the range far above 100 Hz and not more than 1000 Hz. In the range up to 1000 Hz, Physt is dominant in the original high permeability state and the state of low residual flux density, whereas Pexc in the state of high residual flux density is dominant in the wider range above about 100 Hz. The framework of the statistical theory of power loss has been used for representing the behavior of Pexc/f vs f. It has been found that the number n of the simultaneously active 'Magnetic Objects' linearly varies as n = n0 + Hexc/H0 as a function of the dynamic field Hexc in the range below about 120 Hz, whereas n approximately follows a law of the form n = n0 + (Hexc/H0)^m with 1 < m < 2 in the range far above 100 Hz and not more than 1000 Hz. The values of the field HO in principle related to the microstructure and the domain structure have been calculated for the three states.

关键词： General Properties of Low-frequency Power Losses in Fe-based Nanocrystalline Soft Magnetic Alloys Fe

Impact of the US Economic Crisis on East Asian Economies:Production Networks and Triangular Trade through Chinese Mainland

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China & World Economy 2011年第6期19卷 1-18页

作者： IkuoKuroiwa HiroshiKuwamori Director-General Development Studies CenterInstitute of Developing EconomiesJapan External Trade OrganizationChibaJapan Deputy Director International Input-Output Analysis Studies GroupDevelopment Studies CenterInstitute of Developing EconomiesJapan External Trade OrganizationChibaJapan

This paper investigates the impact of the 2008 economic crisis on industries in East Asia. It attempts to identify the transmission mechanism and the magnitude of the impact of the crisis on industries in East Asia using the updated Asian international input-output table for 2008. The analyses reveal that the crisis significantly affected industrial output of the nine East Asian economies included in the present study. The economies that are deeply involved in production networks were affected most seriously. Our analyses also show that the impact was transmitted to East Asian industries through triangular trade, in which Chinese mainland imports parts and components from neighboring East Asian economies and then exports final products to the US and EU markets. Although such intricate production networks have improved the competitiveness of East Asian economies, they have also increased vulnerability to external shocks.

关键词： Asian international input-output table production network triangular trade

Crosstalk among canonical Wnt and Hippo pathway members in skeletal muscle and at the neuromuscular junction

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Neural Regeneration Research 2025年第9期20卷 2464-2479页

作者： Said Hashemolhosseini Lea Gessler institute of Biochemistry Medical FacultyFriedrich-Alexander-University of Erlangen-NürnbergErlangenGermany

Skeletal muscles are essential for locomotion,posture,and metabolic *** understand physiological processes,exercise adaptation,and muscle-related disorders,it is critical to understand the molecular pathways that underlie skeletal muscle *** process of muscle contra ction,orchestrated by a complex interplay of molecular events,is at the core of skeletal muscle *** contraction is initiated by an action potential and neuromuscular transmission requiring a neuromuscular *** muscle fibers,calcium ions play a critical role in mediating the interaction between actin and myosin filaments that generate *** of calcium release from the sarcoplasmic reticulum plays a key role in excitation-contraction *** development and growth of skeletal muscle are regulated by a network of molecular pathways collectively known as *** regulators coordinate the diffe rentiation of myoblasts into mature muscle *** pathways regulate muscle protein synthesis and hypertrophy in response to mechanical stimuli and nutrient *** ral muscle-related diseases,including congenital myasthenic disorders,sarcopenia,muscular dystrophies,and metabolic myopathies,are underpinned by dys regulated molecular pathways in skeletal *** interventions aimed at preserving muscle mass and function,enhancing regeneration,and improving metabolic health hold promise by targeting specific molecular *** molecular signaling pathways in skeletal muscle include the canonical Wnt signaling pathway,a critical regulator of myogenesis,muscle regeneration,and metabolic function,and the Hippo signaling *** recent years,more details have been uncovered about the role of these two pathways during myogenesis and in developing and adult skeletal muscle fibers,and at the neuromuscular *** fact,research in the last few years now suggests that these two signaling pathways are interconnected and

关键词： canonical Wnt"Wingless-related integration site"pathway beta-catenin(CTNNB1) Hippo pathway myogenesis myotube neuromuscular junction satellite cell skeletal muscle fiber transcriptional co-activator with PDZ-binding motif(TAZ) T-cell-specific transcription factor/lymphoid enhancer-binding factor(TCF/LEF) TEA domain family member(TEAD) transducin-like enhancer of split(TLE) yes-associated protein 1(YAP1)

Nucleotide sequence conservation of novel and established cis-regulatory sites within the tyrosine hydroxylase gene promoter

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Frontiers in Biology 2015年第1期10卷 74-90页

作者： Meng WANG Kasturi BANERJEE Harriet BAKER John W. CAVE Burke Medical Research institute White Plains NY 10605 USA Weill Cornell Medical College Brain and mind Research institute NY 10065 USA

Tyrosine hydroxylase （TH） is the rate-limiting enzyme in catecholamine biosynthesis and its gene proximal promoter （〈 1 kb upstream from the transcription start site） is essential for regulating transcription in both the developing and adult nervous systems. Several putative regulatory elements within the TH proximal promoter have been reported, but evolutionary conservation of these dements has not been thoroughly investigated. Since many vertebrate species are used to model development, function and disorders of human catecholaminergic neurons, identifying evolutionarily conserved transcription regulatory mechanisms is a high priority. In this study, we align TH proximal promoter nucleotide sequences from several vertebrate species to identify evolutionarUy conserved motifs. This analysis identified three elements （a TATA box, cyclic AMP response element （CRE） and a 5＇-GGTGG-3＇ site） that constitute the core of an ancient vertebrate TH promoter. Focusing on only eutherian mammals, two regions of high conservation within the proximal promoter were identified： a -250 bp region adjacent to the transcription start site and a -85 bp region located approximately 350 bp further upstream. Within both regions, conservation of previously reported cis-regulatory motifs and human single nucleotide variants was evaluated. Transcription reporter assays in a TH-expressing cell line demonstrated the functionality of highly conserved motifs in the proximal promoter regions and electromobility shift assays showed that brain-region specific complexes assemble on these motifs. These studies also identified a non-canonical CRE binding （CREB） protein recognition element in the proximal promoter. Together, these studies provide a detailed analysis of evolutionary conservation within the TH promoter and identify potential cisregulatory motifs that underlie a core set of regulatory mechanisms in mammals.

关键词： catecholamine dopamine transcription evolution

Single-step thermal carburization synthesis of supported molybdenum carbides from molybdenum-containing methyl-silica

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Journal of Natural Gas Chemistry 2011年第3期20卷 271-280页

作者： Juan Zou Minglin Xiang Bo How Dong Wu Yuhan Sun Hunan Changling Petrochemical S＆T developing Co. Ltd. Yueyang 414012 Hunan China State Key Laboratory of Coal Conversion Institute of Coal Chemistry Chinese Academy of Sciences Taiyuan 030001 Shanxi China

A novel synthesis route to obtain highly dispersed molybdenum carbides in porous silica is described. The synthesis was carried out by a single-step heat treatment of molybdenum-containing and methyl-modified silica （Mo-M-SiO2） in argon atmosphere at 973 K. Mo-M-SiO2 precursor was facilely obtained via a one-pot synthesis route, using （NH4）6Mo7O24 4H2O （AHM） as molybdenum sources and polymethylhydrosiloxane （PMHS） as silica sources at the initial synthetic step. The optimal C/Mo molar ratio in reaction system for complete carburization of molybdenum species was 7. The carburization process of molybdenum species followed a nontopotactic route involving a MoO2 intermediate phase, which was evidenced by XRD, N2 adsorption-desorption and in situ XPS. Formation mechanism of Mo-M-SiO2 precursor was also proposed by observation of the reaction between AHM and PMHS with TEM. Furthermore, by adding TEOS into silica sources and adjusting TEOS/PMHS mass ratio, crystal phase of molybdenum carbides transferred from β-Mo2C to α-MoC1-x, and SiO2 structure changed from microporous to micro/mesoporous. Catalytic performances of samples were tested using CO hydrogenation as a probe reaction. The supported molybdenum carbides exhibited high selectivity for higher alcohol synthesis compared with bulk β-Mo2C and α-MoC1-x.

关键词： molybdenum carbides porous silica single-step carburization one-pot synthesis CO hydrogenation