Search | Engineering

订阅投稿

首页学术期刊学术焦点学术视频工程成就工程前沿关于我们 English

资源类型

期刊论文 364

年份

2023 27

2022 37

2021 39

2020 25

2019 32

2018 12

2017 18

2016 15

2015 15

2014 14

2013 18

2012 8

2011 12

2010 10

2009 14

2008 21

2007 15

2006 6

2005 1

2004 3

展开︾

关键词

复合材料 5

半旱地农业 3

PP 2

农业节水 2

力学性能 2

可持续性 2

复合镀层 2

抗菌 2

机械性能 2

组合梁 2

BMI树脂 1

CCS 1

CO₂分离 1

EFP 1

HDPE 1

Pd局域环境 1

WPC 1

Zn-Fe-SiO2 1

丁醇 1

展开︾

检索范围：

排序：展示方式：

Bending and rotational behaviour of semi-continuous composite beams

WANG Jingfeng, LI Guoqiang

《结构与土木工程前沿（英文）》 2008年第2卷第2期页码 116-122 doi: 10.1007/s11709-008-0015-9

摘要： Stresses and deflections were measured in various semi-continuous composite beams. The bending and rotational capacities of the composite connections were measured in terms of beam curvatures and deflections by using two full-scale semi-rigid composite frames with monotonic loadings. The effect of semi-rigid connections on the performance of composite beams with various loadings was compared with predictions and codes. The tests show that the semi-continuous composite beams are more economic and effective than the simple or continuous composite beams. The semi-rigid connections affect the bending capacities and beam deflections, so the connection behavior should be considered in the design of composite beams. Yielding analysis of the steel beam bottom flange has some influence on the deflection calculation of composite beams.

关键词： rotational effective deflection calculation semi-continuous composite full-scale semi-rigid

HTML PDF 收藏

Removal of dyes from wastewater by growing fungal pellets in a semi-continuous mode

Tao Lu, Qilei Zhang, Shanjing Yao

《化学科学与工程前沿（英文）》 2017年第11卷第3期页码 338-345 doi: 10.1007/s11705-017-1644-0

摘要： To increase the efficiency of dye removal from wastewater using mycelial pellets, a bubble column reactor with a simple structure was designed and efficiently used to remove dyes from solution containing dyes. The mycelial pellets were prepared by marine fungus ZJUBE-1. Eight dyes were tested as dye targets for the adsorption capacity of mycelial pellets and good removal results were obtained. Eriochrome black T was selected as a model dye for characterizing the adsorption processes in detail. The measurement results of Zeta potential and FT-IR analysis indicate that the electrostatic attraction may play a key role in the biosorption process. The bubble column reactor was utilized to study the batch dye-removal efficiency of mycelial pellets. A re-culture process between every two batches, which was under non-sterile condition, successfully enhanced the utilization of mycelium biomass. The dye removal rate is 96.4% after 12 h in the first batch and then decreases slowly in the following batches. This semi-continuous mode, which consists of commutative processes of dye-removal and re-culture, has some outstanding advantages, such as low power consumption, easy operation, high dye removal rate, and efficient biomass utilization.

关键词： dye mycelial pellets marine fungus bubble column reactor semi-continuous biosorption

HTML PDF 收藏

Seismic performance of fabricated continuous girder bridge with grouting sleeve-prestressed tendon composite

《结构与土木工程前沿（英文）》页码 827-854 doi: 10.1007/s11709-023-0954-1

摘要： The seismic performance of a fully fabricated bridge is a key factor limiting its application. In this study, a fiber element model of a fabricated concrete pier with grouting sleeve-prestressed tendon composite connections was built and verified. A numerical analysis of three types of continuous girder bridges was conducted with different piers: a cast-in-place reinforced concrete pier, a grouting sleeve-fabricated pier, and a grouting sleeve-prestressed tendon composite fabricated pier. Furthermore, the seismic performance of the composite fabricated pier was investigated. The results show that the OpenSees fiber element model can successfully simulate the hysteresis behavior and failure mode of the grouted sleeve-fabricated pier. Under traditional non-near-fault ground motions, the pier top displacements of the grouting sleeve-fabricated pier and the composite fabricated pier were less than those of the cast-in-place reinforced concrete pier. The composite fabricated pier had a good self-centering capability. In addition, the plastic hinge zones of the grouting sleeve-fabricated pier and the composite fabricated pier shifted to the joint seam and upper edge of the grouting sleeve, respectively. The composite fabricated pier with optimal design parameters has good seismic performance and can be applied in high-intensity seismic areas; however, the influence of pile-soil interaction on its seismic performance should not be ignored.

关键词： seismic performance continuous girder bridge grouting sleeve-prestressed tendon composite connections grouted sleeve connection design parameters

HTML PDF 收藏

Uncertainty propagation in dynamics of composite plates: A semi-analytical non-sampling-based approach

Mahdi FAKOOR, Hadi PARVIZ

《结构与土木工程前沿（英文）》 2020年第14卷第6期页码 1359-1371 doi: 10.1007/s11709-020-0658-8

摘要： In this study, the influences of spatially varying stochastic properties on free vibration analysis of composite plates were investigated via development of a new approach named the deterministic-stochastic Galerkin-based semi-analytical method. The material properties including tensile modulus, shear modulus, and density of the plate were assumed to be spatially varying and uncertain. Gaussian fields with first-order Markov kernels were utilized to define the aforementioned material properties. The stochastic fields were decomposed via application of the Karhunen-Loeve theorem. A first-order shear deformation theory was assumed, following which the displacement field was defined using admissible trigonometric modes to derive the potential and kinetic energies. The stochastic equations of motion of the plate were obtained using the variational principle. The deterministic-stochastic Galerkin-based method was utilized to find the probability space of natural frequencies, and the corresponding mode shapes of the plate were determined using a polynomial chaos approach. The proposed method significantly reduced the size of the mathematical models of the structure, which is very useful for enhancing the computational efficiency of stochastic simulations. The methodology was verified using a stochastic finite element method and the available results in literature. The sensitivity of natural frequencies and corresponding mode shapes due to the uncertainty of material properties was investigated, and the results indicated that the higher-order modes are more sensitive to uncertainty propagation in spatially varying properties.

关键词： composite plate spatially varying stochastic properties Galerkin method polynomial chaos approach semi-analytical approach

HTML PDF 收藏

Probabilistic stability of uncertain composite plates and stochastic irregularity in their buckling modeshapes: A semi-analytical non-intrusive approach

《结构与土木工程前沿（英文）》页码 179-190 doi: 10.1007/s11709-022-0888-z

摘要： In this study, the mechanical properties of the composite plate were considered Gaussian random fields and their effects on the buckling load and corresponding mode shapes were studied by developing a semi-analytical non-intrusive approach. The random fields were decomposed by the Karhunen−Loève method. The strains were defined based on the assumptions of the first-order and higher-order shear-deformation theories. Stochastic equations of motion were extracted using Euler–Lagrange equations. The probabilistic response space was obtained by employing the non-intrusive polynomial chaos method. Finally, the effect of spatially varying stochastic properties on the critical load of the plate and the irregularity of buckling mode shapes and their sequences were studied for the first time. Our findings showed that different shear deformation plate theories could significantly influence the reliability of thicker plates under compressive loading. It is suggested that a linear relationship exists between the mechanical properties’ variation coefficient and critical loads’ variation coefficient. Also, in modeling the plate properties as random fields, a significant stochastic irregularity is obtained in buckling mode shapes, which is crucial in practical applications.

关键词： uncertain composite plate stochastic assume mode method Karhunen−Loève theorem polynomial chaos approach plate buckling irregularity in buckling mode shapes

HTML PDF 收藏

Decreasing complexity of glucose time series derived from continuous glucose monitoring is correlated

《医学前沿（英文）》 2023年第17卷第1期页码 68-74 doi: 10.1007/s11684-022-0955-9

摘要： Most information used to evaluate diabetic statuses is collected at a special time-point, such as taking fasting plasma glucose test and providing a limited view of individual’s health and disease risk. As a new parameter for continuously evaluating personal clinical statuses, the newly developed technique “continuous glucose monitoring” (CGM) can characterize glucose dynamics. By calculating the complexity of glucose time series index (CGI) with refined composite multi-scale entropy analysis of the CGM data, the study showed for the first time that the complexity of glucose time series in subjects decreased gradually from normal glucose tolerance to impaired glucose regulation and then to type 2 diabetes (P for trend < 0.01). Furthermore, CGI was significantly associated with various parameters such as insulin sensitivity/secretion (all P < 0.01), and multiple linear stepwise regression showed that the disposition index, which reflects β-cell function after adjusting for insulin sensitivity, was the only independent factor correlated with CGI (P < 0.01). Our findings indicate that the CGI derived from the CGM data may serve as a novel marker to evaluate glucose homeostasis.

关键词： complexity of glucose time series continuous glucose monitoring impaired glucose regulation insulin secretion and sensitivity refined composite multi-scale entropy

HTML PDF 收藏

Field validation of UHPC layer in negative moment region of steel-concrete composite continuous girder

Minghong QIU; Xudong SHAO; Weiye HU; Yanping ZHU; Husam H. HUSSEIN; Yaobei HE; Qiongwei LIU

《结构与土木工程前沿（英文）》 2022年第16卷第6期页码 744-761 doi: 10.1007/s11709-022-0843-z

摘要： Improving the cracking resistance of steel-normal concrete (NC) composite beams in the negative moment region is one of the main tasks in designing continuous composite beam (CCB) bridges due to the low tensile strength of the NC deck at pier supports. This study proposed an innovative structural configuration for the negative bending moment region in a steel-concrete CCB bridge with the aid of ultrahigh performance concrete (UHPC) layer. In order to investigate the feasibility and effectiveness of this new UHPC jointed structure in the negative bending moment region, field load testing was conducted on a newly built full-scale bridge. The newly designed structural configuration was described in detail regarding the structural characteristics (cracking resistance, economy, durability, and constructability). In the field investigation, strains on the surface of the concrete bridge deck, rebar, and steel beam in the negative bending moment region, as well as mid-span deflection, were measured under different load cases. Also, a finite element model for the four-span superstructure of the full-scale bridge was established and validated by the field test results. The simulated results in terms of strains and mid-span deflection showed moderate consistency with the test results. This field test and the finite element model results demonstrated that the new configuration with the UHPC layer provided an effective alternative for the negative bending moment region of the composite beam.

关键词： field test steel-concrete composite beam continuous girder bridge negative bending moment region ultrahigh performance concrete

HTML PDF 收藏

Micromixing performance of the teethed high shear mixer under semi-batch operation

《化学科学与工程前沿（英文）》 2022年第16卷第4期页码 546-559 doi: 10.1007/s11705-021-2069-3

摘要： Semi-batch operated reaction processes are necessary for some competitive reaction systems to achieve a desirable process selectivity and productivity of fine chemical products. Herein the structural and operating parameters of the teethed high shear mixers were adjusted to study the micromixing performance in the semi-batch operated system, using the Villermaux/Dushman reaction system. The results indicate that the rising of the rotor speed and the number of rotor teeth, the decrease of the width of the shear gap and the radial distance between the feed position and the inner wall of stator can enhance the micromixing level and lead to the decrease of the segregation index. Additionally, computational fluid dynamics calculations were carried out to disclose the evolution of the flow pattern and turbulent energy dissipation rate of the semi-batch operated high shear mixer. Furthermore, the correlation was established with a mean relative error of 8.05% and R² of 0.955 to fit the segregation index and the parameters studied in this work, which can provide valuable guidance on the design and optimization of the semi-batch operated high shear mixers in practical applications.

关键词： high shear mixer semi-batch operation micromixing performance Villermaux/Dushman system segregation index

HTML PDF 收藏

Strain and process engineering toward continuous industrial fermentation

《化学科学与工程前沿（英文）》 2023年第17卷第10期页码 1336-1353 doi: 10.1007/s11705-022-2284-6

摘要： Most current biotechnology industries are based on batch or fed-batch fermentation processes, which often show low productivity and high production costs compared to chemical processes. To increase the economic competitiveness of biological processes, continuous fermentation technologies are being developed that offer significant advantages in comparison with batch/fed-batch fermentation processes, including: (1) removal of potential substrates and product inhibition, (2) prolonging the microbial exponential growth phase and enhancing productivity, and (3) avoiding repeated fermentation preparation and lowering operation and installation costs. However, several key challenges should be addressed for the industrial application of continuous fermentation processes, including (1) contamination of the fermentation system, (2) degeneration of strains, and (3) relatively low product titer. In this study, we reviewed and discussed metabolic engineering and synthetic biology strategies to address these issues.

关键词： continuous fermentation productivity contamination strain degeneration metabolic engineering

HTML PDF 收藏

Ant colony optimization in continuous problem

YU Ling, LIU Kang, LI Kaishi

《机械工程前沿（英文）》 2007年第2卷第4期页码 459-462 doi: 10.1007/s11465-007-0079-6

摘要： Based on the analysis of the basic ant colony optimization and optimum problem in a continuous space, an ant colony optimization (ACO) for continuous problem is constructed and discussed. The algorithm is efficient and beneficial to the study of the ant colony optimization in a continuous space.

关键词： beneficial algorithm efficient continuous ACO

HTML PDF 收藏

Prediction of the theoretical and semi-empirical model of ambient temperature

Foued CHABANE,Noureddine MOUMMI,Abdelhafid BRIMA,Abdelhafid MOUMMI

《能源前沿（英文）》 2016年第10卷第3期页码 268-276 doi: 10.1007/s11708-016-0413-y

摘要： It is well known that the ambient temperature is a sensitive parameter which has a great effect on biology, technology, geology and even on human behavior. A prediction is a statement about an uncertain event. It is often, but not always, based upon experience or knowledge. Although guaranteed accurate information about the future is in many cases impossible, prediction can be useful to assist in making plans about possible developments. As a result, temperature profiles can be developed which accurately represent the expected ambient temperature exposure that this environment experiences during measurement. The ambient temperature over time is modeled based on the previous and data and using a Lagrange interpolation. To observe the comprehensive variation of ambient temperature the profile must be determined numerically. The model proposed in this paper can provide an acceptable way to measure the change in ambient temperature.

关键词： ambient temperature environment correlation theoretical model semi-empirical

HTML PDF 收藏

Cavitation in semi-open centrifugal impellers for a miniature pump

LUO Xianwu, LIU Shuhong, ZHANG Yao, XU Hongyuan

《能源前沿（英文）》 2008年第2卷第1期页码 31-35 doi: 10.1007/s11708-008-0011-8

摘要： Cavitation in miniature pumps was investigated experimentally for two semi-open centrifugal impellers. Although both impellers had the same blade cross-section, one impeller had a two-dimensional blade, while the other had a leaned blade. The flows were also analyzed using a numerical model of the three-dimensional turbulent flow in the pumps near the peak efficiency point using the -? turbulence model and the VOF cavitation model. The average cavitation performance of each impeller was satisfactorily predicted by the numerical simulations. The results show that the miniature pumps have similar cavitation performances as an ordinary-size pump, with the cavitation performance of the semi-open impeller reduced by increased axial tip clearances. Also, both the hydraulic and cavitation performance of the semi-open impeller were improved by the leaned blade. The results also show that uniform flow upstream of the impeller inlet will improve the cavitation performance of a miniature pump.

关键词： cavitation performance semi-open impeller increased two-dimensional efficiency

HTML PDF 收藏

连续铸钢前沿技术的工程化

干勇

《中国工程科学》 2002年第4卷第9期页码 12-18

摘要：

论述了具有我国自主知识产权的高效连铸和薄板坯连铸工程化关键技术的特点；介绍了连续铸钢领域轻压下、液压非正弦振动、电磁连铸等前沿技术的开发现状；阐述了传统连铸技术超高效率、高品质化及近终形连铸、电磁连铸开发的研发方向。

关键词：连续铸钢高效连铸薄板坯连铸轻压下电磁连铸

HTML PDF 收藏

Utilization of waste vanadium-bearing resources in the preparation of rare-earth vanadate catalysts for semi-hydrogenation

《化学科学与工程前沿（英文）》 2022年第16卷第12期页码 1793-1806 doi: 10.1007/s11705-022-2191-x

摘要： Recycling industrial solid waste not only saves resources but also eliminates environmental concerns of toxic threats. Herein, we proposed a new strategy for the utilization of petrochemical-derived carbon black waste, a waste vanadium-bearing resource (V > 30000 ppm (10 ⁻⁶)). Chemical leaching was employed to extract metallic vanadium from the waste and the leachate containing V was used as an alternative raw material for the fabrication of vanadate nanomaterials. Through the screening of various metal cations, it was found that the contaminated Na⁺ during the leaching process showed strong competitive coordination with the vanadium ions. However, by adding foreign Ce³⁺ and Y³⁺ cations, two rare-earth vanadates, viz., flower-like CeVO₄ and spherical YVO₄ nanomaterials, were successfully synthesized. Characterization techniques such as scanning electron microscopy, transmission electron microscopy, X-ray diffraction, energy-dispersive X-ray spectroscopy, Fourier-transform infrared, and N₂ physisorption were applied to analyze the physicochemical properties of the waste-derived nanomaterials. Importantly, we found that rare-earth vanadate catalysts exhibited good activities toward the semi-hydrogenation of α,β-unsaturated aldehydes. The conversion of cinnamaldehyde and cinnamic alcohol selectivity were even higher than those of the common CeVO₄ prepared using pure chemicals (67.2% vs. 27.7% and 88.4% vs. 53.5%). Our work provides a valuable new reference for preparing vanadate catalysts by the use of abundant vanadium-bearing waste resources.

关键词： petrochemical solid wastes vanadium recovery resource utilization nanomaterials semi-hydrogenation

HTML PDF 收藏

Anti-biofouling strategies for implantable biosensors of continuous glucose monitoring systems

《化学科学与工程前沿（英文）》页码 1866-1878 doi: 10.1007/s11705-023-2340-x

摘要： Continuous glucose monitoring (CGM) systems play an increasingly vital role in the glycemic control of patients with diabetes mellitus. However, the immune responses triggered by the implantation of poorly biocompatible sensors have a significant impact on the accuracy and lifetime of CGM systems. In this review, research efforts over the past few years to mitigate the immune responses by enhancing the anti-biofouling ability of sensors are summarized. This review divided these works into active immune engaging strategy and passive immune escape strategy based on their respective mechanisms. In each strategy, the various biocompatible layers on the biosensor surface, such as drug-releasing membranes, hydrogels, hydrophilic membranes, anti-biofouling membranes based on zwitterionic polymers, and bio-mimicking membranes, are described in detail. This review, therefore, provides researchers working on implantable biosensors for CGM systems with vital information, which is likely to aid in the research and development of novel CGM systems with profound anti-biofouling properties.

关键词： implantable glucose biosensor anti-biofouling continuous glucose monitoring immune responses

HTML PDF 收藏

标题作者时间类型操作

Bending and rotational behaviour of semi-continuous composite beams

WANG Jingfeng, LI Guoqiang

期刊论文

Removal of dyes from wastewater by growing fungal pellets in a semi-continuous mode

Tao Lu, Qilei Zhang, Shanjing Yao

期刊论文

Seismic performance of fabricated continuous girder bridge with grouting sleeve-prestressed tendon composite

期刊论文

Uncertainty propagation in dynamics of composite plates: A semi-analytical non-sampling-based approach

Mahdi FAKOOR, Hadi PARVIZ

期刊论文

Probabilistic stability of uncertain composite plates and stochastic irregularity in their buckling modeshapes: A semi-analytical non-intrusive approach

期刊论文

Decreasing complexity of glucose time series derived from continuous glucose monitoring is correlated

期刊论文

Field validation of UHPC layer in negative moment region of steel-concrete composite continuous girder

Minghong QIU; Xudong SHAO; Weiye HU; Yanping ZHU; Husam H. HUSSEIN; Yaobei HE; Qiongwei LIU

期刊论文

Micromixing performance of the teethed high shear mixer under semi-batch operation

期刊论文

Strain and process engineering toward continuous industrial fermentation

期刊论文

Ant colony optimization in continuous problem

YU Ling, LIU Kang, LI Kaishi