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Modified landfill gas generation rate model of first-order kinetics and two-stage reaction

Jiajun CHEN , Hao WANG , Na ZHANG ,

《环境科学与工程前沿（英文）》 2009年 第3卷 第3期   页码 313-319 doi: 10.1007/s11783-009-0025-4

摘要： This investigation was carried out to establish a new domestic landfill gas (LFG) generation rate model that takes into account the impact of leachate recirculation. The first-order kinetics and two-stage reaction (FKTSR) model of the LFG generation rate includes mechanisms of the nutrient balance for biochemical reaction in two main stages. In this study, the FKTSR model was modified by the introduction of the outflow function and the organic acid conversion coefficient in order to represent the in-situ condition of nutrient loss through leachate. Laboratory experiments were carried out to simulate the impact of leachate recirculation and verify the modified FKTSR model. The model calibration was then calculated by using the experimental data. The results suggested that the new model was in line with the experimental data. The main parameters of the modified FKTSR model, including the LFG production potential (), the reaction rate constant in the first stage (), and the reaction rate constant in the second stage () of 64.746 L, 0.202 d, and 0.338 d, respectively, were comparable to the old ones of 42.069 L, 0.231 d, and 0.231 d. The new model is better able to explain the mechanisms involved in LFG generation.

关键词： landfill gas (LFG)     generation rate model     first-order kinetics     two-stage reaction     outflow function    

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bioaccumulation, trophic transfer and risk assessment of trace elements in fish from a typical shallow outflow

《环境科学与工程前沿（英文）》 2024年 第18卷 第7期 doi: 10.1007/s11783-024-1849-7

摘要：

● Surface water, sediment, and different fish species were analysed in this study.

关键词： Trophic level     Bioaccumulation     Risk assessment     Trace elements    

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Characterization of submicron aerosols in the urban outflow of the central Pearl River Delta region of

Zhaoheng GONG, Zijuan LAN, Lian XUE, Liwu ZENG, Lingyan HE, Xiaofeng HUANG

《环境科学与工程前沿（英文）》 2012年 第6卷 第5期   页码 725-733 doi: 10.1007/s11783-012-0441-8

摘要： Submicron aerosol particles (with aerodynamic diameters less than 1 μm, PM ) were sampled and measured in Heshan, an urban outflow site of Guangzhou megacity in Pearl River Delta in South China, using an Aerodyne High-Resolution Time-of-Flight Aerosol Mass Spectrometer (HR-ToF-AMS) in November 2010 during 2010 Guangzhou Asian Games. The mean PM mass concentration measured was 47.9±17.0 μg·m during the campaign, with organic aerosol (OA) and sulfate being the two dominant species, accounting for 36.3% and 20.9% of the total mass, respectively, followed by black carbon (17.1%, measured by an aethalometer), nitrate (12.9%), ammonium (9.6%) and chloride (3.1%). The average size distributions of the species (except black carbon) were dominated by an accumulation mode peaking at ~550 nm. Calculations based on high-resolution organic mass spectrum showed that, C, H, O and N on average contributed 58.1%, 7.3%, 30.7%, and 3.9% to the total organic mass, respectively. The average ratio of organic mass over organic carbon mass (OM/OC) was 1.73±0.08. Four components of OA were identified by the Positive Matrix Factorization (PMF) analysis, including a hydrocarbon-like (HOA), a biomass burning (BBOA) and two oxygenated (SV-OOA and LV-OOA) organic aerosol components, which on average accounted for 18.0%, 14.3%, 28.8% and 38.9% of the total organic mass, respectively.

关键词： organic aerosol     high-resolution time-of-flight aerosol mass spectrometer (HR-ToF-AMS)     positive matrix factorization    

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Lung function and air pollution exposure in adults with asthma in Beijing: a 2-year longitudinal panel

《医学前沿（英文）》 2022年 第16卷 第4期   页码 574-583 doi: 10.1007/s11684-021-0882-1

摘要： The effect of air pollution on the lung function of adults with asthma remains unclear to date. This study followed 112 patients with asthma at 3-month intervals for 2 years. The pollutant exposure of the participants was estimated using the inverse distance weight method. The participants were divided into three groups according to their lung function level at every visit. A linear mixed-effect model was applied to predict the change in lung function with each unit change in pollution concentration. Exposure to carbon monoxide (CO) and particles less than 2.5 micrometers in diameter (PM2.5) was negatively associated with large airway function in participants. In the severe group, exposure to chronic sulfur dioxide (SO2) was negatively associated with post-bronchodilator forced expiratory flow at 50%, between 25% and 75% of vital capacity % predicted (change of 95% CI per unit: −0.34 (−0.55, −0.12), −0.24 (−0.44, −0.03), respectively). In the mild group, the effect of SO2 on the small airways was similar to that in the severe group, and it was negatively associated with large airway function. Exposure to CO and PM2.5 was negatively associated with the large airway function of adults with asthma. The negative effects of SO2 were more evident and widely observed in adults with severe and mild asthma than in adults with moderate asthma. Patients with asthma react differently to air pollutants as evidenced by their lung function levels.

关键词： lung function     asthma     air pollution     adult    

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The function and regulation of OTU deubiquitinases

Jiansen Du, Lin Fu, Yingli Sui, Lingqiang Zhang

《医学前沿（英文）》 2020年 第14卷 第5期   页码 542-563 doi: 10.1007/s11684-019-0734-4

摘要： Post-translational modification of cellular proteins by ubiquitin regulates numerous cellular processes, including cell division, immune responses, and apoptosis. Ubiquitin-mediated control over these processes can be reversed by deubiquitinases (DUBs), which remove ubiquitin from target proteins and depolymerize polyubiquitin chains. Recently, much progress has been made in the DUBs. In humans, the ovarian tumor protease (OTU) subfamily of DUBs includes 16 members, most of which mediate cell signaling cascades. These OTUs show great variation in structure and function, which display a series of mechanistic features. In this review, we provide a comprehensive analysis of current progress in character, structure and function of OTUs, such as the substrate specificity and catalytic activity regulation. Then we discuss the relationship between some diseases and OTUs. Finally, we summarize the structure of viral OTUs and their function in immune escape and viral survival. Despite the challenges, OTUs might provide new therapeutic targets, due to their involvement in key regulatory processes.

关键词： ubiquitin     OTU deubiquitinases     structure     function     regulation    

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类差分平衡函数的性质及其应用

张文英,李世取

《中国工程科学》 2004年 第6卷 第3期   页码 45-52

摘要：

定义了布尔函数的类差分和类差分平衡函数，研究了类差分平衡函数的密码学性质以及构造方法。作为类差分平衡函数的应用，给出了〓上逻辑函数是完全非线性函数的充要条件，并在首先分析得到所有四元类差分平衡函数的基础上，编程搜索出〓上所有的完全非线性函数。

关键词： Bent函数     完全非线性函数     2-基展开     类差分     类自相关函数     类差分平衡函数    

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Quality Function Deployment Implementation in Construction: A Systematic Literature Review

Elizabeth A. Cudney,William L. Gillis

《工程管理前沿（英文）》 2016年 第3卷 第3期   页码 224-230 doi: 10.15302/J-FEM-2016036

摘要： The construction of new buildings represents a significant investment. The goal of new building construction is to maximize value and minimize cost while staying on time and within budget. Translating customer requirements into engineering terms for new construction design is vital for a construction project to be successful. Quality function deployment has been successfully used in product development to capture the voice of the customer and translate it into engineering characteristics. Quality function deployment then carries these parameters into production and service to ensure the voice of the customer is being met with the final product. The house of quality, a tool within quality function deployment, can provide a means for comparison of owner’s project requirements and the proposed design, along with identifying how the design decisions impact meeting customer requirements and green building requirements. Quality function deployment can effectively link the project phases through design and construction and into operations and maintenance to ensure the owner’s project requirements are met with the final building. This research identifies and categorizes studies of quality function deployment applications in construction. The research method used is a systematic literature review from databases related to quality function deployment in the construction industry published in the periodicals through 2016. The principal findings of implementations, practices, and integrated approaches are then summarized. This article intends to propel further research of quality function deployment in the construction sector.

关键词： construction     engineering management     quality function deployment     systematic review    

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Design and evaluation of a novel biopsy needle with hemostatic function

《机械工程前沿（英文）》 2023年 第18卷 第2期 doi: 10.1007/s11465-022-0738-7

摘要： Biopsy is a method commonly used for early cancer diagnosis. However, bleeding complications of widely available biopsy are risky for patients. Safer biopsy will result in a more accurate cancer diagnosis and a decrease in the risk of complications. In this article, we propose a novel biopsy needle that can reduce bleeding during biopsy procedures and achieve stable hemostasis. The proposed biopsy needle features a compact structure and can be operated easily by left and right hands. A predictive model for puncture force and tip deflection based on coupled Eulerian–Lagrangian (CEL) method is developed. Experimental results show that the biopsy needle can smoothly deliver the gelatin sponge hemostatic plug into the tissue. Although the hemostatic plug bends, the overall delivery process is stable, and the hemostatic plug retains in the tissue without being affected by the withdrawal of the needle. Further experiments indicate that the specimens are well obtained and evenly distributed in the groove of the outer needle without scattering. Our proposed design of biopsy needle possesses strong ability of hemostasis, tissue cutting, and tissue retention. The CEL model accurately predicts the peak of puncture force and produces close estimation of the insertion force at the postpuncture stage and tip position.

关键词： cancer diagnosis     biopsy needle     hemostatic function     predictive model     coupled Eulerian−Lagrangian    

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Transfer function solving, simulating and testing of thermal dynamics characteristics of a ballscrew

Junyong XIA, Bo WU, Youmin HU, Tielin SHI,

《机械工程前沿（英文）》 2010年 第5卷 第2期   页码 233-241 doi: 10.1007/s11465-010-0014-0

摘要： Based on the theory of heat transfer, the transfer function between the thermal deformation of any point on the lead screw and the temperature of heat sources of a ballscrew under the influence of multi-changeable heat sources is solved by using the Laplace transform method. By solving the amplitude-frequency characteristics and phase-frequency characteristics of the transfer function, the steady-state response of thermal deformation of the ballscrew is obtained, and the thermal dynamics characteristics of the lead screw under the influence of multi-heat sources are further studied. Comparing with the result of finite-element simulation, the theoretical analyzing result accords with the steady-state part of the finite-element simulating result. Through tests of the steady-state response of thermal deformation, the thermal dynamics characteristics are further studied. The curves of tests by and large accord with the theoretical analyzing result, which shows that the method of transfer function is correct and valid in solving the steady-state response of thermal deformation.

关键词： ballscrew     Laplace transform     transfer function     thermal dynamic characteristics    

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Regulation and function of histone acetyltransferase MOF

null

《医学前沿（英文）》 2014年 第8卷 第1期   页码 79-83 doi: 10.1007/s11684-014-0314-6

摘要：

The mammalian MOF (male absent on the first), a member of the MYST (MOZ, YBF2, SAS2, and Tip60) family of histone acetyltransferases (HATs), is the major enzyme that catalyzes the acetylation of histone H4 on lysine 16. Acetylation of K16 is a prevalent mark associated with chromatin decondensation. MOF has recently been shown to play an essential role in maintaining normal cell functions. In this study, we discuss the important roles of MOF in DNA damage repair, apoptosis, and tumorigenesis. We also analyze the role of MOF as a key regulator of the core transcriptional network of embryonic stem cells.

关键词： MOF     histone acetyltransferase     DNA damage repair     tumorigenesis     embryonic stem cells    

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Comparison in executive function in Chinese preterm and full-term infants at eight months

null

《医学前沿（英文）》 2018年 第12卷 第2期   页码 164-173 doi: 10.1007/s11684-017-0540-9

摘要：

Executive function (EF) is increasingly recognized as being responsible for adverse developmental outcomes in preterm-born infants. Several perinatal factors may lead to poor EF development in infancy, and the deficits in EF can be identified in infants as young as eight months. A prospective cohort study was designed to study the EF in Chinese preterm infants and examine the relationship between EF in preterm infants and maternal factors during perinatal period. A total of 88 preterm infants and 88 full-term infants were followed from birth to eight months (corrected age). Cup Task and Planning Test was applied to assess the EF of infants, and the Bayley Scale of Infant Development (BSID-III) was used to evaluate cognitive (MDI) and motor abilities (PDI) of infants. In comparison with full-term infants, the preterm infants performed more poorly on all measures of EF including working memory, inhibition to prepotent responses, inhibition to distraction, and planning, and the differences remained after controlling the MDI and PDI. Anemia and selenium deficiency in mothers during pregnancy contributed to the differences in EF performance. However, maternal depression, hypertension, and diabetes during pregnancy were not related to the EF deficits in preterm infants. Future research should focus on the prevention of anemia and selenium deficiency during pregnancy and whether supplementing selenium in mothers during pregnancy can prevent further deterioration and the development of adverse outcomes of their offspring.

关键词： executive function (EF)     preterm infant     working memory     inhibition to prepotent response     inhibition to distraction     planning    

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Calculation of collision frequency function for aerosol particles in free molecule regime in presence

Xiaowei LUO, Yannick BENICHOU, Suyuan YU

《能源前沿（英文）》 2013年 第7卷 第4期   页码 506-510 doi: 10.1007/s11708-013-0275-5

摘要： The collision frequency function for aerosol particles has already been calculated for the free molecule regime and for the continuum range. The present work, taking into account the influence of internal force fields such as magnetic force, electric force and molecular forces, created by particles themselves, recalculated the collision frequency in the case of particles much smaller than the mean free path of the gas (free molecule regime). Attractive forces increase naturally the collision frequency, while repulsive forces decrease it. The calculation was performed for all types of central forces deriving from a potential, including Coulomb forces and Van der Waals forces.

关键词： aerosol particles     collision frequency function     coagulation    

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Improved approach to quality function deployment based on Pythagorean fuzzy sets and application to assembly

Huchang LIAO, Yinghan CHANG, Di WU, Xunjie GOU

《工程管理前沿（英文）》 2020年 第7卷 第2期   页码 196-203 doi: 10.1007/s42524-019-0038-z

摘要： Quality function deployment (QFD) is an effective method that helps companies analyze customer requirements (CRs). These CRs are then turned into product or service characteristics, which are translated to other attributes. With the QFD method, companies could design or improve the quality of products or services close to CRs. To increase the effectiveness of QFD, we propose an improved method based on Pythagorean fuzzy sets (PFSs). We apply an extended method to obtain the group consensus evaluation matrix. We then use a combined weight determining method to integrate former weights to objective weights derived from the evaluation matrix. To determine the exact score of each PFS in the evaluation matrix, we develop an improved score function. Lastly, we apply the proposed method to a case study on assembly robot design evaluation.

关键词： quality function deployment     Pythagorean fuzzy sets     group consensus     combined weights     assembly robot design    

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Effects of modafinil on vestibular function during 24 hour sleep deprivation

ZHAN Hao, XIE Sujiang, JIA Hongbo, WEI Sihuang, JING Baisheng

《医学前沿（英文）》 2007年 第1卷 第2期   页码 226-229 doi: 10.1007/s11684-007-0044-0

摘要： The aim of this research was to investigate the effects of modafinil, a new wake-promoting agent, on vestibular function during 24 h sleep deprivation (SD) so as to provide experimental evidence for the rational use of this drug among air crew. Eight young, healthy male volunteers were exposed to two 24 h periods of continuous wakefulness during the crossover experiment. Initially, 200 mg dose of modafinil was given, and one week later, a matching placebo was administered. The SD time started from 08:00 of the first day to 08:00 of the second day. Drugs were given at 0:00 on the second day. Vestibular function was tested at 21:00 on the first day and 1, 3, 5, 7 h after drug administration. The accuracy of saccade tracking and gains in visual-vestibular optokinetic reflex (VVOR) and optokinetic nystagmus (OKN) in the placebo group decreased during 24 h SD, especially at 01:00 05:00 on the second day, while OKN gains in the modafinil group increased significantly. There were no significant differences in the other vestibular functional indices between the modafinil group and placebo group. The 24 h SD can influence vestibular function to a certain degree, but modafinil may improve OKN.

关键词： VVOR     modafinil     Vestibular function     vestibular functional     Initially    

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A valveless piezoelectric pump with novel flow path design of function of rectification to improve energy

《机械工程前沿（英文）》 2022年 第17卷 第3期 doi: 10.1007/s11465-022-0685-3

摘要： Existing valveless piezoelectric pumps are mostly based on the flow resistance mechanism to generate unidirectional fluid pumping, resulting in inefficient energy conversion because the majority of mechanical energy is consumed in terms of parasitic loss. In this paper, a novel tube structure composed of a Y-shaped tube and a ȹ-shaped tube was proposed considering theory of jet inertia and vortex dissipation for the first time to improve energy efficiency. After verifying its feasibility through the flow field simulation, the proposed tubes were integrated into a piezo-driven chamber, and a novel valveless piezoelectric pump with the function of rectification (NVPPFR) was reported. Unlike previous pumps, the reported pump directed the reflux fluid to another flow channel different from the pumping fluid, thus improving pumping efficiency. Then, mathematical modeling was established, including the kinetic analysis of vibrator, flow loss analysis of fluid, and pumping efficiency. Eventually, experiments were designed, and results showed that NVPPFR had the function of rectification and net pumping effect. The maximum flow rate reached 6.89 mL/min, and the pumping efficiency was up to 27%. The development of NVPPFR compensated for the inefficiency of traditional valveless piezoelectric pumps, broadening the application prospect in biomedicine and biology fields.

关键词： composite tube     valveless piezoelectric pump     rectification     energy efficiency    

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标题 作者 时间 类型 操作

Modified landfill gas generation rate model of first-order kinetics and two-stage reaction

Jiajun CHEN , Hao WANG , Na ZHANG ,

期刊论文

bioaccumulation, trophic transfer and risk assessment of trace elements in fish from a typical shallow outflow

期刊论文

Characterization of submicron aerosols in the urban outflow of the central Pearl River Delta region of

Zhaoheng GONG, Zijuan LAN, Lian XUE, Liwu ZENG, Lingyan HE, Xiaofeng HUANG

期刊论文

Lung function and air pollution exposure in adults with asthma in Beijing: a 2-year longitudinal panel

期刊论文

The function and regulation of OTU deubiquitinases

Jiansen Du, Lin Fu, Yingli Sui, Lingqiang Zhang

期刊论文

类差分平衡函数的性质及其应用

张文英,李世取

期刊论文

Quality Function Deployment Implementation in Construction: A Systematic Literature Review

Elizabeth A. Cudney,William L. Gillis

期刊论文

Design and evaluation of a novel biopsy needle with hemostatic function

期刊论文

Transfer function solving, simulating and testing of thermal dynamics characteristics of a ballscrew

Junyong XIA, Bo WU, Youmin HU, Tielin SHI,

期刊论文

Regulation and function of histone acetyltransferase MOF

null

期刊论文

Comparison in executive function in Chinese preterm and full-term infants at eight months

null

期刊论文

Calculation of collision frequency function for aerosol particles in free molecule regime in presence

Xiaowei LUO, Yannick BENICHOU, Suyuan YU

期刊论文

Improved approach to quality function deployment based on Pythagorean fuzzy sets and application to assembly

Huchang LIAO, Yinghan CHANG, Di WU, Xunjie GOU

期刊论文

Effects of modafinil on vestibular function during 24 hour sleep deprivation

ZHAN Hao, XIE Sujiang, JIA Hongbo, WEI Sihuang, JING Baisheng

期刊论文

A valveless piezoelectric pump with novel flow path design of function of rectification to improve energy

期刊论文