资源类型

期刊论文 67

年份

2023 3

2022 6

2021 4

2020 3

2019 7

2018 2

2017 2

2016 5

2014 5

2013 1

2012 2

2011 1

2010 3

2009 4

2008 9

2007 4

2004 3

2003 2

展开 ︾

关键词

力常数 2

狭义相对论 2

键能 2

键长 2

4D打印 1

乳液共聚合 1

光速不变公设 1

光量子 1

凸极同步电机 变速恒频 交流励磁 双馈 1

分段线性回归 1

制造业 1

刺激响应材料 1

力矩反馈器 1

原子光谱 1

双馈型 1

变流器 1

变速恒频 1

多尺度优化 1

并网逆变器;模型预测控制;直接功率控制;三矢量;恒定开关频率;功率误差 1

展开 ︾

检索范围:

排序: 展示方式:

Biosorption of Cu(II) to extracellular polymeric substances (EPS) from

Xiangliang PAN, Jing LIU, Wenjuan SONG, Daoyong ZHANG

《环境科学与工程前沿(英文)》 2012年 第6卷 第4期   页码 493-497 doi: 10.1007/s11783-012-0416-9

摘要: Biosorption of extracellular polymeric substances (EPS) from sp. (cyanobacterium) with Cu(II) was investigated using fluorescence spectroscopy. Three fluorescence peaks were found in the excitation-emission matrix (EEM) fluorescence spectra of EPS. Fluorescence of peak A (Ex/Em= 275/452 nm) and peak C (Ex/Em= 350/452 nm) were originated from humic-like substances and fluorescence of peak B (Ex/Em= 275/338 nm) was attributed to protein-like substances. Fluorescence of peaks A, B, and C could be quenched by Cu(II). The effective quenching constants (lg K ) were 2.8–5.84 for peak A, 6.4–9.24 for peak B, and 3.48–6.68 for peak C, respectively. The values of lg K showed a decreasing trend with increasing temperature, indicating that the quenching processes were static in nature. The binding constants (lg K ) followed the order of peak A>peak B>peak C, implying that the humic-like substances in EPS have greater Cu(II) binding capacity than the protein-like substances. The binding site number, , in EPS-Cu(II) complexes for peaks A, B, and C was less than 1. This suggests the negative cooperativity between multiple binding sites and the presence of more than one Cu binding site.

关键词: biosorption     conditional binding constant     extracellular polymeric substances (EPS)     fluorescence quenching    

Named entity recognition for Chinese construction documents based on conditional random field

《工程管理前沿(英文)》 2023年 第10卷 第2期   页码 237-249 doi: 10.1007/s42524-021-0179-8

摘要: Named entity recognition (NER) is essential in many natural language processing (NLP) tasks such as information extraction and document classification. A construction document usually contains critical named entities, and an effective NER method can provide a solid foundation for downstream applications to improve construction management efficiency. This study presents a NER method for Chinese construction documents based on conditional random field (CRF), including a corpus design pipeline and a CRF model. The corpus design pipeline identifies typical NER tasks in construction management, enables word-based tokenization, and controls the annotation consistency with a newly designed annotating specification. The CRF model engineers nine transformation features and seven classes of state features, covering the impacts of word position, part-of-speech (POS), and word/character states within the context. The F1-measure on a labeled construction data set is 87.9%. Furthermore, as more domain knowledge features are infused, the marginal performance improvement of including POS information will decrease, leading to a promising research direction of POS customization to improve NLP performance with limited data.

关键词: NER     NLP     Chinese language     construction document    

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.    

Proteomics study of Mycoplasma pneumoniae pneumonia reveals the Fc fragment of the IgG-binding protein

《医学前沿(英文)》 2022年 第16卷 第3期   页码 378-388 doi: 10.1007/s11684-021-0840-y

摘要: Macrolide and corticosteroid resistance has been reported in patients with Mycoplasma pneumoniae (MP) pneumonia (MPP). MP clearance is difficult to achieve through antibiotic treatment in sensitive patients with severe MPP (SMPP). SMPP in children might progress to airway remodeling and even bronchiolitis/bronchitis obliterans. Therefore, identifying serum biomarkers that indicate MPP progression and exploring new targeted drugs for SMPP treatment require urgency. In this study, serum samples were collected from patients with general MPP (GMPP) and SMPP to conduct proteomics profiling. The Fc fragment of the IgG-binding protein (FCGBP) was identified as the most promising indicator of SMPP. Biological enrichment analysis indicated uncontrolled inflammation in SMPP. ELISA results proved that the FCGBP level in patients with SMPP was substantially higher than that in patients with GMPP. Furthermore, the FCGBP levels showed a decreasing trend in patients with GMPP but the opposite trend in patients with SMPP during disease progression. Connectivity map analyses identified 25 possible targeted drugs for SMPP treatment. Among them, a mechanistic target of rapamycin kinase (mTOR) inhibitor, which is a macrolide compound and a cell proliferation inhibitor, was the most promising candidate for targeting SMPP. To our knowledge, this study was the first proteomics-based characterization of patients with SMPP and GMPP.

关键词: severe Mycoplasma pneumoniae pneumonia     children     proteomics     Fc fragment of the IgG-binding protein     mechanistic target of rapamycin kinase inhibitor    

Chloride binding and time-dependent surface chloride content models for fly ash concrete

S. MUTHULINGAM,B. N. RAO

《结构与土木工程前沿(英文)》 2016年 第10卷 第1期   页码 112-120 doi: 10.1007/s11709-015-0322-x

摘要: Corrosion of embedded rebars is a classical deterioration mechanism of reinforced concrete structures exposed to chloride environments. Such environments can be attributed to the presence of seawater, deicing or sea-salts, which have high concentrations of chloride ion. Chloride ingress into concrete, essential for inducing rebar corrosion, is a complex interaction between many physical and chemical processes. The current study proposes two chloride ingress parameter models for fly ash concrete, namely: 1) surface chloride content under tidal exposure condition; and 2) chloride binding. First, inconsistencies in surface chloride content and chloride binding models reported in literature, due to them not being in line with past research studies, are pointed out. Secondly, to avoid such inconsistencies, surface chloride content and chloride binding models for fly ash concrete are proposed based upon the experimental work done by other researchers. It is observed that, proposed models are simple, consistent and in line with past research studies reported in literature.

关键词: binding isotherms     chloride ingress     concrete     fly ash     surface chloride content    

Coupling the porous conditional moment closure with the random pore model: applications to gasification

D. N. SAULOV, C. R. CHODANKA, M. J. CLEARY, A. Y. KLIMENKO

《化学科学与工程前沿(英文)》 2012年 第6卷 第1期   页码 84-93 doi: 10.1007/s11705-011-1164-2

摘要: Gasification of coal or biomass with in situ CO capture simultaneously allows production of clean hydrogen at relatively low cost and reduced emission of CO into the atmosphere. Clearly, this technology has a great potential for a future carbon constrained economy. Therefore, the development of a comprehensive, physically-based gasifier model is important. The sub-models that describe reactive transport processes in coal particles as well as in particles of CO sorbent material are among the key sub-models, which provide a necessary input for an overall gasifier model. Both coal and sorbent are materials that have complicated pore structures. The porous conditional moment closure (PCMC) model proves to be adequate for modeling reactive transport through porous media with fixed pore structure. Consumption of coal in the heterogeneous gasification reaction, however, widens the pores and reduces the surface area available for this reaction. At the same time, formation of a carbonate layer narrows the pores in the sorbent material and reduces the reaction rate of CO sorption. In both cases the pore structures are affected. Such changes are not taken into account in the existing PCMC model. In this study, we obtain the parameters of the diffusive tracer distribution based on the pore size distribution given by the widely applied random pore model (RPM), while coupling PCMC with RPM. Such coupling allows taking into account changes in pore structure caused by heterogeneous reactions and thus improves the accuracy of these key sub-models.

关键词: gasification     CO2 capture     PCMC     RPM    

reduces IgE binding ability of allergenic egg white proteins

Sen LI, Marina OFFENGENDEN, Michael G. GÄNZLE, Jianping WU

《农业科学与工程前沿(英文)》 2018年 第5卷 第3期   页码 373-381 doi: 10.15302/J-FASE-2018210

摘要:

Egg white proteins are one of the major allergens. The objective of this study was to investigate the effect of Aspergillus oryzae cultivation on IgE binding ability of egg white proteins. Effect of A. oryzae on egg white proteins was determined using ninhydrin method, SDS-PAGE, ELISA, fluorescence FITC labeling, MALDI-TOF-MS and LC-MS/MS analysis. Adding mycelium of A. oryzae ATCC 1011 and 16868 substantially reduced the IgE binding ability of acidified egg white after 24 h incubation. The binding capacity of egg white proteins to IgE in plasma from four egg allergy patients was almost completely lost after incubation with mycelium of ATCC 16868. Results from SDS-PAGE, free amino acid analysis, MALDI-TOF-MS and LC-MS/MS indicated that there was no substantial protein degradation during incubation. Therefore, the reduction of IgE binding ability of egg white proteins during A. oryzae treatment was probably due to a loss of ~1700 Da mass including a fragment of the ovomucoid N terminus.

关键词: Aspergillus oryzae     egg allergy     egg white proteins     IgE-binding ability     ovomucoid    

Quantitative characterization of Cu binding potential of dissolved organic matter (DOM) in sediment from

Yuan ZHANG,Yan ZHANG,Tao YU

《环境科学与工程前沿(英文)》 2014年 第8卷 第5期   页码 666-674 doi: 10.1007/s11783-013-0608-y

摘要: Dissolved organic matter (DOM) plays an important role in heavy metal speciation and distribution in the aquatic environment especially for eutrophic lakes which have higher DOM concentration. Taihu Lake is the third largest freshwater and a high eutrophic lake in the downstream of the Yangtze River, China. In the lake, frequent breakout of algae blooms greatly increased the concentration of different organic matters in the lake sediment. In this study, sediment samples were collected from various part of Taihu Lake to explore the spatial difference in the binding potential of DOM with Cu. The titration experiment was adopted to quantitatively characterize the interaction between Cu(II) and DOM extracted from Taihu Lake sediments using ion selective electrode (ISE) and fluorescence quenching technology. The ISE results showed that the exogenous DOM had higher binding ability than endogenous DOM, and DOM derived from aquatic macrophytes had a higher binding ability than that derived from algae. The fluorescence quenching results indicated that humic substances played a key role in the complexation between DOM and Cu(II) in the lake. However, because of the frequent breakout of algae blooms, protein-like matters are also main component like humic matters in Taihu Lake. Therefore, the metals bound by protein-like substances should be caused concern as protein-like substances in DOM were unstable and they will release bound metal when decomposed.

关键词: binding ability     dissolved organic matters     fluorescence quenching     complex capacity     Taihu Lake    

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    

Repression of CDKN2C caused by PML/RARα binding promotes the proliferation and differentiation block

null

《医学前沿(英文)》 2016年 第10卷 第4期   页码 420-429 doi: 10.1007/s11684-016-0478-3

摘要:

Inappropriate cell proliferation during oncogenesis is often accompanied by inactivation of components involved in the cell cycle machinery. Here, we report that cyclin-dependent kinase inhibitor 2C (CDKN2C) as a member of the cyclin-dependent kinase inhibitors is a target of the PML/RARα oncofusion protein in leukemogenesis of acute promyelocytic leukemia (APL). We found that CDKN2C was markedly downregulated in APL blasts compared with normal promyelocytes. Chromatin immunoprecipitation combined with quantitative polymerase chain reaction demonstrated that PML/RARα directly bound to the CDKN2C promoter in the APL patient-derived cell line NB4. Luciferase assays indicated that PML/RARα inhibited the CDKN2C promoter activity in a dose-dependent manner. Furthermore, all-trans retinoic acid treatment induced CDKN2C expression by releasing the PML/RARα binding on chromatin in NB4 cells. Functional studies showed that ectopic expression of CDKN2C induced a cell cycle arrest at the G0/G1 phase and a partial differentiation in NB4 cells. Finally, the transcriptional regulation of CDKN2C was validated in primary APL patient samples. Collectively, this study highlights the importance of CDKN2C inactivation in the abnormal cell cycle progression and differentiation block of APL cells and may provide new insights into the study of pathogenesis and targeted therapy of APL.

关键词: CDKN2C     acute promyelocytic leukemia     cell cycle arrest     differentiation    

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    

Association of miRNA-122-binding site polymorphism at the interleukin-1 α gene and its interaction with

null

《医学前沿(英文)》 2014年 第8卷 第2期   页码 217-226 doi: 10.1007/s11684-014-0326-2

摘要:

This study was designed to investigate the contribution of miRNA-122-binding site polymorphism at the IL-1A gene and its multiplicative interactions with hepatitis B virus (HBV) mutations in the risk of hepatocellular carcinoma (HCC). A total of 1021 healthy controls, 302 HBV surface antigen (HBsAg) seroclearance subjects, and 2011 HBsAg-positive subjects (including 1021 HCC patients) were enrolled in this study. Quantitative PCR was used to genotype rs3783553. HBV mutations were determined by direct sequencing. Multivariate logistic regression analyses were performed to test the associations of rs3783553, mutations, and their interactions with the risk of HCC. No significant association was found between rs3783553 and the risk of HCC among healthy controls, HBsAg seroclearance subjects, HBsAg-positive subjects without HCC, and all controls. Additionally, rs3783553 was not significantly associated with chronic HBV infection, liver cirrhosis, HBV e antigen seroconversion, abnormal alanine aminotransferase, and high viral load (>104 copies/ml). However, the TTCA insertion allele of rs3783553 was significantly associated with an increased frequency of HBV C7A mutation compared with homozygous TTCA deletion carriers [(del/ins+ ins/ins) vs. del/del, adjusted odds ratio (OR)=1.48, 95% confidence interval (CI)=1.09-2.02, P=0.013]. Multiplicative interaction of rs3783553 with HBV preS deletion significantly reduced the risk of HCC in males, with an adjusted OR of 0.64 (95% CI=0.42-0.98; P=0.041) after age and HBV genotype were adjusted. Although rs3783553 did not significantly affect genetic susceptibility to HBV-related HCC, its variant allele may predispose the host to selecting HBV C7A mutation during evolution and significantly reduce the risk of HCC caused by HBV preS deletion. This study provides an insight into the complex host-virus interaction in HBV-induced hepatocarcinogenesis and is helpful in determining HBsAg-positive subjects who are likely to develop HCC.

关键词: hepatocellular carcinoma (HCC)     interaction     miRNA-122-binding site     IL-1A     rs3783553     hepatitis B virus (HBV) mutations    

Diffusive gradients in thin films using molecularly imprinted polymer binding gels for in situ measurements

Ying Cui, Feng Tan, Yan Wang, Suyu Ren, Jingwen Chen

《环境科学与工程前沿(英文)》 2020年 第14卷 第6期 doi: 10.1007/s11783-020-1290-5

摘要: Abstract • Selective molecularly imprinted polymer (MIP) binding gel was prepared. • MIP-DGT showed excellent uptake performance for antibiotics. • In situ measurement of antibiotics in wastewaters via MIP-DGT was developed. • The MIP-DGT method was robust, reliable, and highly sensitive. Urban wastewater is one of main sources for the introduction of antibiotics into the environment. Monitoring the concentrations of antibiotics in wastewater is necessary for estimating the amount of antibiotics discharged into the environment through urban wastewater treatment systems. In this study, we report a novel diffusive gradient in thin films (DGT) method based on molecularly imprinted polymers (MIPs) for in situ measurement of two typical antibiotics, fluoroquinolones (FQs) and sulfonamides (SAs) in urban wastewater. MIPs show specific adsorption toward their templates and their structural analogs, resulting in the selective uptake of the two target antibiotics during MIP-DGT deployment. The uptake performance of the MIP-DGTs was evaluated in the laboratory and was relatively independent of solution pH (4.0–9.0), ionic strength (1–750 mmol/L), and dissolved organic matter (DOM, 0–20 mg/L). MIP-DGT samplers were tested in the effluent of an urban wastewater treatment plant for field trials, where three SA (sulfamethoxazole, sulfapyridine, and trimethoprim) and one FQ (ofloxacin) antibiotics were detected, with concentrations ranging from 25.50 to 117.58 ng/L, which are consistent with the results measured by grab sampling. The total removal efficiency of the antibiotics was 80.1% by the treatment plant. This study demonstrates that MIP-DGT is an effective tool for in situ monitoring of trace antibiotics in complex urban wastewaters.

关键词: Diffusive gradients in thin films     Molecularly imprinted polymers     Selective uptake     Antibiotics     Passive sampling    

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    

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    

标题 作者 时间 类型 操作

Biosorption of Cu(II) to extracellular polymeric substances (EPS) from

Xiangliang PAN, Jing LIU, Wenjuan SONG, Daoyong ZHANG

期刊论文

Named entity recognition for Chinese construction documents based on conditional random field

期刊论文

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

期刊论文

Proteomics study of Mycoplasma pneumoniae pneumonia reveals the Fc fragment of the IgG-binding protein

期刊论文

Chloride binding and time-dependent surface chloride content models for fly ash concrete

S. MUTHULINGAM,B. N. RAO

期刊论文

Coupling the porous conditional moment closure with the random pore model: applications to gasification

D. N. SAULOV, C. R. CHODANKA, M. J. CLEARY, A. Y. KLIMENKO

期刊论文

reduces IgE binding ability of allergenic egg white proteins

Sen LI, Marina OFFENGENDEN, Michael G. GÄNZLE, Jianping WU

期刊论文

Quantitative characterization of Cu binding potential of dissolved organic matter (DOM) in sediment from

Yuan ZHANG,Yan ZHANG,Tao YU

期刊论文

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

Shantanu ACHARYA,Subhadeep BHATTACHARJEE

期刊论文

Repression of CDKN2C caused by PML/RARα binding promotes the proliferation and differentiation block

null

期刊论文

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

期刊论文

Association of miRNA-122-binding site polymorphism at the interleukin-1 α gene and its interaction with

null

期刊论文

Diffusive gradients in thin films using molecularly imprinted polymer binding gels for in situ measurements

Ying Cui, Feng Tan, Yan Wang, Suyu Ren, Jingwen Chen

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

The energy consumption in a batch stripper and a batch rectifier

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

期刊论文