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Stability of an annular viscous liquid jet in compressible gases with different properties inside and outside of the jet

Chunji YAN, Maozhao XIE,

《能源前沿（英文）》 2010年 第4卷 第2期   页码 198-204 doi: 10.1007/s11708-009-0054-5

摘要： A spatial linear instability analysis is conducted on an annular viscous liquid jet injected into compressible gases and a three-dimensional model of the jet is developed. The model takes into account differences between the velocities, densities of the gases inside and outside of the liquid jet. Theoretical analysis reveals that there exist 9 dimensionless parameters controlling the instability of the liquid jet. Numerical computations reveal some basic characteristics in the breakup and atomization process of the liquid jet as well as influences of these relevant parameters. Major observations and findings of this study are as follows. The Mach number plays a destabilizing role and the inner Mach number has a greater effect on the jet instability than the outer Mach number. The Reynolds number always tends to promote the instabilities of the liquid jet, but its influence is very limited. The Weber number and the gas-to-liquid density ratio also have unstable effects and can improve the atomization of liquid jets. Furthermore, the effects of the Weber number and gas-to-liquid density ratio on the maximum growth rates of axisymmetric and non-axisymmetric disturbances and corresponding dominant wave numbers are manifested in a linear way, while that of the Mach number is non-linear. The effect of Reynolds on the maximum growth rates is non-linear, but the dominant wavenumber is almost not affected by the Reynolds number.

关键词： liquid jet     dominant wave number     compressibility     instability    

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Time reversal method for guided wave inspection in pipes

DENG Fei, WU Bin, HE Cunfu

《机械工程前沿（英文）》 2008年 第3卷 第3期   页码 251-260 doi: 10.1007/s11465-008-0050-1

摘要： The application of the time reversal method in pipe-like structures based on finite element method (FEM) is investigated. A steel pipe model measuring 70 mm × 3.5 mm is used to analyze the reflection coefficient of the (0,2) mode with the time reversal process. Simulation results show that the time reversal array method is beneficial to the improvement of the signal-to-noise ratio of a guided wave inspection system. As the intercepting window is widened, more energy is included in re-emitted signals, which leads to a large reflection coefficient of the (0,2) mode. In parallel, a circumferential locating method based on the time reversal method is described. The time reversal process used for guided wave inspection leads to the temporal and spatial focusing. When the time reversal signals are re-emitted, the angular profile obtained at the axial location of the defect can be used to determine the circumferential location of the defect. Except for a pipe with one defect, the circumferential locating method has been verified on another pipe model with two defects. Meanwhile, the elements number of the time reversal array has been discussed for enhancing the discrimination of the defect circumferential location.

关键词： reversal process     beneficial     circumferential location     energy     number    

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Roles of integrin β3 cytoplasmic tail in bidirectional signal transduction in a trans-dominant inhibition

null

《医学前沿（英文）》 2016年 第10卷 第3期   页码 311-319 doi: 10.1007/s11684-016-0460-0

摘要：

We evaluated the roles of calpain cleavage-related mutations of the integrin β3 cytoplasmic tail in integrin αIIbβ3 bidirectional signaling using a trans-dominant inhibition model. Chimeric Tac-β3 proteins (i.e., Tac-β3, Tac-β3D741, Tac-β3D747, Tac-β3D754, Tac-β3D759, and Tac-β3DNITY) consisting of the extracellular and transmembrane domains of human IL-2 receptor (Tac) and the human integrin β3 cytoplasmic domain were stably expressed in the 123 CHO cells harboring human glycoprotein Ib-IX and wild-type integrin αIIbβ3. The different cells were assayed for stable adhesion and spreading on immobilized fibrinogen, and for binding soluble fibrinogen representing outside-in and inside-out signaling events, respectively. The chimeric protein Tac-β3 inhibited, and Tac-β3DNITY partially attenuated stable adhesion and spreading. Tac-β3, Tac-β3D759, Tac-β3DNITY, and Tac-β3D754, but not Tac-β3D747 or Tac-β3D741, impaired the soluble fibrinogen binding. Results indicated that the bidirectional signaling was significantly inhibited by Tac-β3 and Tac-β3DNITY, albeit to a much lesser extent. Moreover, only inside-out signaling was impaired in the 123/Tac-β3D759 and 123/Tac-β3D754 cells in contrast to an intact bidirectional signaling in the 123/Tac-β3D747 and 123/Tac-β3D741 cells. In conclusion, the calpain cleavage of integrin β3 resulted in the regulatory effects on signaling by interrupting its interaction with cytoplasmic proteins rather than altering its conformation, and may thus regulate platelet function.

关键词： integrin β3     signal transduction     trans-dominant inhibition model    

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Investigation of polyhydroxyalkanoates (PHAs) biosynthesis from mixed culture enriched by valerate-dominant

Jiuxiao Hao, Xiujin Wang, Hui Wang

《环境科学与工程前沿（英文）》 2017年 第11卷 第1期 doi: 10.1007/s11783-017-0896-8

摘要： Valerate-hydrolysate enriched culture showed great ability to produce 3HV and 3H2MV. Valerate-hydrolysate enriched culture had more in the community. Mixed iso-/n-valerate was effective at balancing microbial growth and PHAs synthesis. Co-substrates of valerate and propionate raised the fraction of 3HV and 3H2MV. The production of polyhydroxyalkanoates (PHAs) with a high fraction of 3-hydroxyvalerate (3HV) and 3-hydroxy-2-methylvalerate (3H2MV) from mixed culture enriched by valerate-dominant hydrolysate was evaluated in this study. After long-term enrichment, the culture showed strong ability to synthesize 3HV and 3H2MV, even with acetate-dominant substrate. The ultilization of single or mixed iso-/n-valerate by the enriched culture showed that the mixture of iso-valerate and n-valerate was more efficient substrate than any single in terms of balancing microbial growth and PHAs synthesis. Besides, through comparing the kinetics and stoichiometry of the tests supplying valerate and propionate, the enriched culture with equivalent valerate and propionate (1:1 molar ratio) exhibited superior PHAs production performances to pure valerate or propionate, attaining more than 70 mol% of 3HV and 3H2MV. The above findings reveal that valerate-dominant hydrolysate is a kind of suitable substrate to enrich PHAs producing culture with great capability to synthesize 3HV and 3H2MV monomers, thus improving product properties than pure poly(3-hydroxybutyrate) (P3HB); also 3HV and 3H2MV production behaviors can be regulated by the type of odd-carbon VFAs in the substrate.

关键词： Polyhydroxyalkanoates (PHAs)     Valerate     Mixed culture     3-hydroxyvalerate (3HV)     Propionate    

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Heavy metal accumulation and phytostabilization potential of dominant plant species growing on manganese

YANG Shengxiang,LIANG Shichu,YI Langbo,XU Bibo,CAO Jianbing,GUO Yifeng,ZHOU Yu

《环境科学与工程前沿（英文）》 2014年 第8卷 第3期   页码 394-404 doi: 10.1007/s11783-013-0602-4

摘要： Screening plants that are hypertolerant to and excluders of certain heavy metals plays a fundamental role in a remediation strategy for metalliferous mine tailings. A field survey of terrestrial higher plants growing on Mn mine tailings at Huayuan, Hunan Province, China was conducted to identify candidate species for application in phytostabilization of the tailings in this region. In total, 51 species belonging to 21 families were recorded and the 12 dominant plants were investigated for their potential in phytostabilization of heavy metals. Eight plant species, , , , , , , , and accumulated much lower concentrations of heavy metals in shoots and roots than the associated soils and bioconcentration factors (BFs) for Cd, Mn, Pb and Zn were all<1, demonstrating a high tolerance to heavy metals and poor metals translocation ability. The field investigation also found that these species grew fast, accumulated biomass rapidly and developed a vegetation cover in a relatively short time. Therefore, they are good candidates for phytostabilization purposes and could be used as pioneer species in phytoremediation of Mn mine tailings in this region of South China.

关键词： Mn mine tailings     heavy metal accumulation     phytostabilization    

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Estimating the number of Chinese cancer patients eligible for and benefit from immune checkpoint inhibitors

《医学前沿（英文）》 2022年 第16卷 第5期   页码 773-783 doi: 10.1007/s11684-021-0902-1

摘要： The total number of cancer patients who are eligible for and will benefit from immune checkpoint inhibitors (ICIs) in China has not been quantified. This cross-sectional study was conducted to estimate the number of Chinese cancer patients with eligibility and response to ICIs based on the 2015 Chinese cancer statistics and the immune checkpoint inhibitor clinical practice guideline of the Chinese Society of Clinical Oncology. A total of 11 ICIs were recommended for 17 cancer types. The estimated number of eligible patients annually was 1 290 156 (55.18%), which included 888 738 males (60.05%) and 400 468 females (46.67%). The estimated number of responders annually was 448 972 (19.20%), which included 309 023 males (20.88%) and 139 764 females (16.29%). Gastric cancer (n=291 000, 12.45%), non-small-cell lung cancer (n=289 629, 12.39%), and hepatocellular carcinoma (n=277 100, 11.85%) were the top three cancer types with the highest number of eligible patients. Non-small-cell lung cancer (n=180 022, 7.70%), hepatocellular carcinoma (n=75 648, 3.24%), and small-cell lung cancer (n=64 362, 2.75%) were the top three cancer types with the highest number of responders. In conclusion, ICIs provide considerable benefit in Chinese cancer patients under optimal estimation.

关键词： benefit     China     eligibility     immune checkpoint inhibitor     public health    

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Identification of structural parameters and boundary conditions using a minimum number of measurement

Ali KARIMPOUR, Salam RAHMATALLA

《结构与土木工程前沿（英文）》 2020年 第14卷 第6期   页码 1331-1348 doi: 10.1007/s11709-020-0686-4

摘要： This article proposes a novel methodology that uses mathematical and numerical models of a structure to build a data set and determine crucial nodes that possess the highest sensitivity. Regression surfaces between the structural parameters and structural output features, represented by the natural frequencies of the structure and local transmissibility, are built using the numerical data set. A description of a possible experimental application is provided, where sensors are mounted at crucial nodes, and the natural frequencies and local transmissibility at each natural frequency are determined from the power spectral density and the power spectral density ratios of the sensor responses, respectively. An inverse iterative process is then applied to identify the structural parameters by matching the experimental features with the available parameters in the myriad numerical data set. Three examples are presented to demonstrate the feasibility and efficacy of the proposed methodology. The results reveal that the method was able to accurately identify the boundary coefficients and physical parameters of the Euler-Bernoulli beam as well as a highway bridge model with elastic foundations using only two measurement points. It is expected that the proposed method will have practical applications in the identification and analysis of restored structural systems with unknown parameters and boundary coefficients.

关键词： structural model validation     eigenvalue problem     response surface     inverse problems    

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Study on wave rotor refrigerators

Yuqiang DAI, Dapeng HU, Meixia DING

《化学科学与工程前沿（英文）》 2009年 第3卷 第1期   页码 83-87 doi: 10.1007/s11705-009-0075-y

摘要： As a novel generation of a rotational gas wave machine, the wave rotor refrigerator (WRR) is an unsteady flow device used for refrigeration, in whose passages pressured streams directly contact and exchange energy due to the movement of pressure waves. In this paper, the working mechanism and refrigeration principle are investigated based on the one-dimensional unsteady flow theory. A basic limitation on main structural parameters and operating parameters is deduced and the wave diagram of WRR to guide designing is sketched. The main influential factors are studied through an experiment. In the DUT Gas Wave Refrigeration Studying and Development Center (GWRSDC) lab, the isentropic efficiency can now reach about 65%. The results show that the WRR is a feasible and promising technology in pressured gas refrigeration cases.

关键词： wave rotor     refrigeration     unsteady flow theory     wave diagram    

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Prediction of the shear wave velocity

Amoroso SARA

《结构与土木工程前沿（英文）》 2014年 第8卷 第1期   页码 83-92 doi: 10.1007/s11709-013-0234-6

摘要： The paper examines the correlations to obtain rough estimates of the shear wave velocity from non-seismic dilatometer tests (DMT) and cone penetration tests (CPT). While the direct measurement of is obviously preferable, these correlations may turn out useful in various circumstances. The experimental results at six international research sites suggest that the DMT predictions of from the parameters (material index), (horizontal stress index), (constrained modulus) are more reliable and consistent than the CPT predictions from (cone resistance), presumably because of the availability, by DMT, of the stress history index .

关键词： horizontal stress index     shear wave velocity     flat dilatometer test     cone penetration test    

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Lamb wave propagation modeling for structure health monitoring

Xiaoyue ZHANG, Shenfang YUAN, Tong HAO

《机械工程前沿（英文）》 2009年 第4卷 第3期   页码 326-331 doi: 10.1007/s11465-009-0045-6

摘要： This study aims to model the propagation of Lamb waves used in structure health monitoring. A number of different numerical computational techniques have been developed for wave propagation studies. The local interaction simulation approach, used for modeling sharp interfaces and discontinuities in complex media (LISA/SIM theory), has been effectively applied to numerical simulations of elastic wave interaction. This modeling is based on the local interaction simulation approach theory and is finally accomplished through the finite elements software Ansys11. In this paper, the Lamb waves propagating characteristics and the LISA/SIM theory are introduced. The finite difference equations describing wave propagation used in the LISA/SIM theory are obtained. Then, an anisotropic metallic plate model is modeled and a simulating Lamb waves signal is loaded on. Finally, the Lamb waves propagation modeling is implemented.

关键词： Lamb wave     modeling     LISA/SIM theory     finite difference equation     finite element    

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Hydrogen production by catalytic gasification of cellulose in supercritical water

GUAN Yu, PEI Aixia, GUO Liejin

《化学科学与工程前沿（英文）》 2008年 第2卷 第2期   页码 176-180 doi: 10.1007/s11705-008-0026-z

摘要： Cellulose, one of the important components of biomass, was gasified in supercritical water to produce hydrogen-rich gas in an autoclave which was operated batch-wise under high-pressure. KCO and Ca(OH) were selected as the catalysts (or promoters). The temperature was kept between 450°C and 500°C while pressure was maintained at 24–26 MPa. The reaction time was 20 min. Experimental results showed that the two catalysts had good catalytic effect and optimum amounts were observed for each catalyst. When 0.2 g KCO was added, the hydrogen yield could reach 9.456 molkg which was two times of the H amount produced without catalyst. When 1.6 g Ca(OH) was added, the H yield was 8.265 molkg which is lower than that obtained using KCO as catalyst but is still 1.7 times that achieved without catalyst. Comparing with the results obtained using KCO or Ca(OH) alone, the use of a combination of KCO and Ca(OH) could increase the H yield by up to 2.5 times that without catalyst and 25% and 45% more than that obtained using KCO and Ca(OH) alone, respectively. It was found that methane was the dominant product at relatively low temperature. When the temperature was increased, the methane reacts with water and is converted to hydrogen and carbon dioxide.

关键词： reaction     temperature     combination     catalytic effect     dominant product    

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Forecast method for used number of parts and components based on complex network

LIU Fu-yun, QI Guo-ning, YANG Qing-hai

《机械工程前沿（英文）》 2006年 第1卷 第4期   页码 479-484 doi: 10.1007/s11465-006-0064-5

摘要： Applying directed complex network to model the main structure of a product family, according to in-degree bi-logarithmic coordinate distribution curve and distribution rule of nodes of the network, in-degree evolving rule of nodes of the network is presented and analytic expression of in-degree probability density of nodes is derived. Through the analysis of the relation between existing kinds of components and existing product numbers, an expression of the relation between kinds of components and product numbers is derived. A forecast method for the increment of component numbers and parts based on the increment of products is presented. As an example, the component numbers of an industrial steam turbine product family is forecasted, forecast result verified and forecast error analyzed.

关键词： complex network     industrial     component     analytic expression     forecast    

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Influence of cetane number improver on performance and emissions of a common-rail diesel engine fueled

Wu YU, Gen CHEN, Zuohua HUANG

《能源前沿（英文）》 2011年 第5卷 第4期   页码 412-418 doi: 10.1007/s11708-011-0163-9

摘要： In this paper, the effect of cetane number (CN) improver on performance and emissions, including particulate number concentration and size distribution, of a turbocharged, common-rail diesel engine fueled with biodiesel-methanol were studied. Two volume fractions (0.3% and 0.6%) of CN improver were added to BM30 (30% of methanol in the biodiesel-methanol blend) in the experiment. The results show that, compared with those of biodiesel-methanol blend, the peak value of cylinder pressure increases, the second peak of heat release rate decreases, the start of second heat release are advanced, and the fuel economy and thermal efficiency are improved when CN improver is added to biodiesel-methanol blend. Besides, CO and HC emissions decrease, NO emission varies little and smoke emissions increase slightly. Moreover, exhaust particles of BM30 mainly distribute in nano-size range. Furthermore, particle number concentration decreases and peak of size distribution profile shifts toward large size direction.

关键词： biodiesel     methanol     common-rail (CR) diesel engine     cetane number (CN) improver    

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Simulation of cross-flow-induced vibration of tube bundle by surface vorticity method

WANG Fenghao, JIANG Gedong, Lin John Zhang

《能源前沿（英文）》 2008年 第2卷 第3期   页码 243-248 doi: 10.1007/s11708-008-0049-7

摘要： A fluid-structure interaction model based on Surface Vorticity Method (SVM) was used to study flow-induced vibrations of tube bundles in medium space ratio. The flow-induced vibrations of four tubes in a rotated square and a staggered tube bundle in three-row and five-column arrangements were simulated in the high sub-critical Reynolds number () range. The results on fluid forces, tube responses and vorticity maps were presented. The vorticity maps of the four rotated-square tubes changed dramatically when the rigid tubes were replaced by the flexible tubes. From the vorticity maps and vibration responses of the staggered tube bundle of different structural parameters, it was found that with the decrease of tube natural frequency, the maximal vibration response moved from the third row to the first. The results also showed that when more flexible tubes are used, the flow pattern changed drastically and the fluid-structure interaction imposed a dominant impact on the flow.

关键词： dominant     sub-critical Reynolds     staggered     Vorticity     three-row    

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involved in nitrogen cycling in wastewater treatment plants using DNA microarray and most probable number-PCR

Junqin PANG, Masami MATSUDA, Masashi KURODA, Daisuke INOUE, Kazunari SEI, Kei NISHIDA, Michihiko IKE

《环境科学与工程前沿（英文）》 2016年 第10卷 第4期 doi: 10.1007/s11783-016-0846-x

摘要： Nitrogen-cycling microbial communities in municipal WWTPs were characterized. Numbers of , and genes were quantified by MPN-PCR. Diversity of whole nitrogen-cycling communities was analyzed with DNA microarray. CAS process retained diverse nitrogen cycling populations. Specific, limited populations may be dominated in nitrogen removal processes. To improve nitrogen removal performance of wastewater treatment plants (WWTPs), it is essential to understand the behavior of nitrogen cycling communities, which comprise various microorganisms. This study characterized the quantity and diversity of nitrogen cycling genes in various processes of municipal WWTPs by employing two molecular-based methods:most probable number-polymerase chain reaction (MPN-PCR) and DNA microarray. MPN-PCR analysis revealed that gene quantities were not statistically different among processes, suggesting that conventional activated sludge processes (CAS) are similar to nitrogen removal processes in their ability to retain an adequate population of nitrogen cycling microorganisms. Furthermore, most processes in the WWTPs that were researched shared a pattern:the and the bacterial genes were more abundant than the and archaeal genes, respectively. DNA microarray analysis revealed that several kinds of nitrification and denitrification genes were detected in both CAS and anaerobic-oxic processes (AO), whereas limited genes were detected in nitrogen removal processes. Results of this study suggest that CAS maintains a diverse community of nitrogen cycling microorganisms; moreover, the microbial communities in nitrogen removal processes may be specific.

关键词： DNA microarray analysis     Nitrogen cycling functional genes     Most probable number-polymerase chain reaction (MPN-PCR)     Wastewater treatment plants (WWTPs)    

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标题 作者 时间 类型 操作

Stability of an annular viscous liquid jet in compressible gases with different properties inside and outside of the jet

Chunji YAN, Maozhao XIE,

期刊论文

Time reversal method for guided wave inspection in pipes

DENG Fei, WU Bin, HE Cunfu

期刊论文

Roles of integrin β3 cytoplasmic tail in bidirectional signal transduction in a trans-dominant inhibition

null

期刊论文

Investigation of polyhydroxyalkanoates (PHAs) biosynthesis from mixed culture enriched by valerate-dominant

Jiuxiao Hao, Xiujin Wang, Hui Wang

期刊论文

Heavy metal accumulation and phytostabilization potential of dominant plant species growing on manganese

YANG Shengxiang,LIANG Shichu,YI Langbo,XU Bibo,CAO Jianbing,GUO Yifeng,ZHOU Yu

期刊论文

Estimating the number of Chinese cancer patients eligible for and benefit from immune checkpoint inhibitors

期刊论文

Identification of structural parameters and boundary conditions using a minimum number of measurement

Ali KARIMPOUR, Salam RAHMATALLA

期刊论文

Study on wave rotor refrigerators

Yuqiang DAI, Dapeng HU, Meixia DING

期刊论文

Prediction of the shear wave velocity

Amoroso SARA

期刊论文

Lamb wave propagation modeling for structure health monitoring

Xiaoyue ZHANG, Shenfang YUAN, Tong HAO

期刊论文

Hydrogen production by catalytic gasification of cellulose in supercritical water

GUAN Yu, PEI Aixia, GUO Liejin

期刊论文

Forecast method for used number of parts and components based on complex network

LIU Fu-yun, QI Guo-ning, YANG Qing-hai

期刊论文

Influence of cetane number improver on performance and emissions of a common-rail diesel engine fueled

Wu YU, Gen CHEN, Zuohua HUANG

期刊论文

Simulation of cross-flow-induced vibration of tube bundle by surface vorticity method

WANG Fenghao, JIANG Gedong, Lin John Zhang

期刊论文

involved in nitrogen cycling in wastewater treatment plants using DNA microarray and most probable number-PCR

Junqin PANG, Masami MATSUDA, Masashi KURODA, Daisuke INOUE, Kazunari SEI, Kei NISHIDA, Michihiko IKE

期刊论文