资源类型

期刊论文 632

会议视频 18

会议信息 1

会议专题 1

年份

2024 2

2023 55

2022 41

2021 59

2020 35

2019 40

2018 35

2017 37

2016 21

2015 27

2014 24

2013 20

2012 31

2011 30

2010 39

2009 41

2008 28

2007 34

2006 7

2005 5

展开 ︾

关键词

低碳经济 6

碳中和 5

低碳发展 4

低渗透 3

低碳 3

高压 3

低成本 2

低渗透油田 2

低温SOFC 2

化石能源 2

天然气 2

泥水盾构 2

综合利用 2

绿色化工 2

能源 2

运载系统 2

10kV高压电力电缆 1

2035 1

2R-1C模型;嵌入式系统;参数估计;非迭代方法;二次型 1

展开 ︾

检索范围:

排序: 展示方式:

Piezoresistive pressure sensor with high sensitivity for medical application using peninsula-island structure

Tingzhong XU, Hongyan WANG, Yong XIA, Zhiming ZHAO, Mimi HUANG, Jiuhong WANG, Libo ZHAO, Yulong ZHAO, Zhuangde JIANG

《机械工程前沿(英文)》 2017年 第12卷 第4期   页码 546-553 doi: 10.1007/s11465-017-0447-9

摘要:

A novel micro-electromechanical systems piezoresistive pressure sensor with a diagonally positioned peninsula-island structure has high sensitivity for ultra-low-pressure measurement. The pressure sensor was designed with a working range of 0–500 Pa and had a high sensitivity of 0.06 mV·V−1·Pa−1. The trade-off between high sensitivity and linearity was alleviated. Moreover, the influence of the installation angle on the sensing chip output was analyzed, and an application experiment of the sensor was conducted using the built pipettor test platform. Findings indicated that the proposed pressure sensor had sufficient resolution ability and accuracy to detect the pressure variation in the pipettor chamber. Therefore, the proposed pressure sensor has strong potential for medical equipment application.

关键词: MEMS     low pressure sensor     peninsula-island     ultra-high sensitivity     medical application    

Theoretical study of failure in composite pressure vessels subjected to low-velocity impact and internalpressure

Roham RAFIEE, Hossein RASHEDI, Shiva REZAEE

《结构与土木工程前沿(英文)》 2020年 第14卷 第6期   页码 1349-1358 doi: 10.1007/s11709-020-0650-3

摘要: A theoretical solution is aimed to be developed in this research for predicting the failure in internally pressurized composite pressure vessels exposed to low-velocity impact. Both in-plane and out-of-plane failure modes are taken into account simultaneously and thus all components of the stress and strain fields are derived. For this purpose, layer-wise theory is employed in a composite cylinder under internal pressure and low-velocity impact. Obtained stress/strain components are fed into appropriate failure criteria for investigating the occurrence of failure. In case of experiencing any in-plane failure mode, the evolution of damage is modeled using progressive damage modeling in the context of continuum damage mechanics. Namely, mechanical properties of failed ply are degraded and stress analysis is performed on the updated status of the model. In the event of delamination occurrence, the solution is terminated. The obtained results are validated with available experimental observations in open literature. It is observed that the sequence of in-plane failure and delamination varies by increasing the impact energy.

关键词: composite pressure vessel     low-velocity impact     failure     theoretical solution     progressive damage modeling    

Numerical investigation and optimal design of fiber Bragg grating based wind pressure sensor

Xiangjie WANG, Danhui DAN, Rong XIAO, Xingfei YAN

《结构与土木工程前沿(英文)》 2017年 第11卷 第3期   页码 286-292 doi: 10.1007/s11709-017-0415-9

摘要: A wind pressure sensor based on fiber Bragg grating (FBG) for engineering structure was investigated in this paper. We established a transaction model of wind pressure to strain and proposed a method of temperature compensation. By finite element analysis, the basic parameters of the sensor were optimized with the aim of maximum strain under the basic wind pressure proposed in relative design code in China taking geometrical non-linearity into consideration. The result shows that the wind pressure sensor we proposed is well performed and have good sensing properties, which means it is a technically feasible solution.

关键词: wind pressure measurement     wind pressure sensor     fiber Bragg grating     optimal design    

Low crosstalk switch unit for dense piezoelectric sensor networks

Lei QIU, Shenfang YUAN,

《机械工程前沿(英文)》 2009年 第4卷 第4期   页码 401-406 doi: 10.1007/s11465-009-0047-4

摘要: Structural health monitoring (SHM), on the basis of piezoelectric (PZT) sensors and lamb wave method, is efficient in estimating the state of monitored structures. Furthermore, to monitor large-scale structures, dense piezoelectric sensor networks are required, which usually contain many piezoelectric sensor pairs called actuator-sensor channels. In that case, considering the few data acquisition channels especially in the data acquisition board with a high sampling rate and limited quantity of signal amplifiers used in an integrated computer system, a switch unit is adopted to switch to different channels. Because of the high frequency and power of the lamb wave excitation signal, there exists a crosstalk signal in the switch unit. A large crosstalk signal is mixed into the response signal so that the on/off-line signal processing task is difficult to achieve. This paper first analyzes the crosstalk signal phenomenon, describes its production mechanism, and proposes a method to reduce it. Then a 24-switch channel low crosstalk switch unit based on a digital I/O board PCI7248 produced by Adlink technology is developed. An experiment is implemented to validate it. Its low crosstalk characteristics make it promote the real application of the SHM based active lamb wave method. Finally, a general software program based on LabVIEW software platform is developed to control this switch unit.

关键词: structural health monitoring (SHM)     piezoelectric (PZT) sensor networks     switch unit     crosstalk signal    

Ionic strength directed self-assembled polyelectrolyte single-bilayer membrane for low-pressure nanofiltration

《化学科学与工程前沿(英文)》 2022年 第16卷 第5期   页码 699-708 doi: 10.1007/s11705-021-2093-3

摘要: Layer-by-layer assembly is a versatile technique for fabricating nanofiltration membranes, where multiple layers of polyelectrolytes are usually required to achieve reasonable separation performance. In this work, an ionic strength directed self-assembly procedure is described for the preparation of nanofiltration membranes consisting of only a single bilayer of poly(diallyldimethylammoniumchloride) and poly(sodium-4-styrenesulfoate). The influence of background ionic strength as well as membrane substrate properties on the formation of single-bilayer membranes are systematically evaluated. Such a simplified polyelectrolyte deposition procedure results in membranes having outstanding separation performance with permeating flux of 14.2 ± 1.5 L∙m–2∙h–1∙bar–1 and Na2SO4 rejection of 97.1% ± 0.8% under a low applied pressure of 1 bar. These results surpass the ones for conventional multilayered polyelectrolyte membranes. This work encompasses an investigation of ionic strength induced coiling of the polyelectrolyte chains and emphasizes the interplay between-polyelectrolyte chain configuration and substrate pore profile. It thus introduces a new concept on the control of membrane fabrication process toward high performance nanofiltration.

关键词: layer-by-layer self-assembly     single bilayer     nanofiltration membrane     desalination    

Using mRNA to investigate the effect of low-pressure ultraviolet disinfection on the viability of

Chao Yang, Wenjun Sun, Xiuwei Ao

《环境科学与工程前沿(英文)》 2019年 第13卷 第2期 doi: 10.1007/s11783-019-1111-x

摘要:

UV can induce damages on mRNA consistently among different genes.

SOS response was more active after UV treatment.

Programmed cell death was not found to be more active after UV treatment.

关键词: UV disinfection     Viability     mRNA     SOS response     Programmed cell death    

Study of the robustness of a low-temperature dual-pressure process for removal of CO

Stefania Moioli, Laura A. Pellegrini, Paolo Vergani, Fabio Brignoli

《化学科学与工程前沿(英文)》 2018年 第12卷 第2期   页码 209-225 doi: 10.1007/s11705-017-1688-1

摘要: The growing use of energy by most of world population and the consequent increasing demand for energy are making unexploited low quality gas reserves interesting from an industrial point of view. To meet the required specifications for a natural gas grid, some compounds need to be removed from the sour stream. Because of the high content of undesired compounds (i.e., CO ) in the stream to be treated, traditional purification processes may be too energy intensive and the overall system may result unprofitable, therefore new technologies are under study. In this work, a new process for the purification of natural gas based on a low temperature distillation has been studied, focusing on the dynamics of the system. The robustness of the process has been studied by dynamic simulation of an industrial-scale plant, with particular regard to the performances when operating conditions are changed. The results show that the process can obtain the methane product with a high purity and avoid the solidification of carbon dioxide.

关键词: CO2 capture     innovative process     cryogenic distillation     dynamic simulation     solid-liquid-vapor equilibrium    

Shrink-induced graphene sensor for alpha-fetoprotein detection with low-cost self-assembly and label-free

Shota SANDO, Bo ZHANG, Tianhong CUI

《机械工程前沿(英文)》 2017年 第12卷 第4期   页码 574-580 doi: 10.1007/s11465-017-0485-3

摘要:

Combination of shrink induced nano-composites technique and layer-by-layer (LbL) self-assembled graphene challenges controlling surface morphology. Adjusting shrink temperature achieves tunability on graphene surface morphology on shape memory polymers, and it promises to be an alternative in fields of high-surface-area conductors and molecular detection. In this study, self-assembled graphene on a shrink polymer substrate exhibits nanowrinkles after heating. Induced nanowrinkles on graphene with different shrink temperature shows distinct surface roughness and wettability. As a result, it becomes more hydrophilic with higher shrink temperatures. The tunable wettability promises to be utilized in, for example, microfluidic devices. The graphene on shrink polymer also exhibits capability of being used in sensing applications for pH and alpha-fetoprotein (AFP) detection with advantages of label free and low cost, due to self-assembly technique, easy functionalization, and antigen-antibody reaction on graphene surface. The detection limit of AFP detection is down to 1 pg/mL, and therefore the sensor also has a significant potential for biosensing as it relies on low-cost self-assembly and label-free assay.

关键词: graphene     self-assembly     shrink polymer     AFP     label-free     biosensor    

Catalytic ozonation of reactive red X-3B in aqueous solution under low pressure: decolorization and OH

Hong SUN,Min SUN,Yaobin ZHANG,Xie QUAN

《环境科学与工程前沿(英文)》 2015年 第9卷 第4期   页码 591-595 doi: 10.1007/s11783-014-0694-5

摘要: Catalytic ozonation of Reactive Red X-3B in aqueous solution had been carried out in an ozone oxidation reactor where Mn-Fe-ceramic honeycomb was used as the catalysts. The presence of Mn-Fe-ceramic honeycomb catalyst could obviously improve the decoloration efficiency of Reactive Red X-3B and the utilization efficiency of ozone compared to the results from non-catalytic ozonation. Adsorption of Reactive Red X-3B had no obviously influence on the degradation efficiency. Addition of tert-butanol significantly decreased the degradation efficiency, indicating that the degradation of Reactive Red X-3B followed the mechanism of hydroxyl radical (OH·) oxidation. The operating variables such as reaction pressure and ozone supply had a positive influence on the degradation efficiency, mainly attributing to facilitate the ozone decomposition and OH· formation.

关键词: catalytic ozonation     reactive red X-3B     ceramic honeycomb     hydroxyl radical (OH·)    

Spray characteristics of high-pressure swirl injector fueled with alcohol

WANG Xibin, CHEN Wansheng, GAO Jian, JIANG Deming, HUANG Zuohua

《能源前沿(英文)》 2007年 第1卷 第1期   页码 105-112 doi: 10.1007/s11708-007-0012-z

摘要: The spray characteristics of methanol and ethanol with high-pressure swirl injector were explored experimentally and numerically. Experimental results show that the spray characteristics of methanol and ethanol had displayed the same trends as that of gasoline. Under the low back-pressure ambient conditions, the spray behavior exhibited a hollow cone with wide spray angle and initial spray slug at the tip, while the spray presented a solid cone in the case of high back-pressure. Vortexes in the opposite direction existed in the rear part of the spray under low back-pressure ambient conditions while the vortexes formed in the middle part under high back-pressure ambient conditions. Experiments also showed that methanol had the largest cone angle, while ethanol and gasoline presented almost the same cone angle. Simulation results indicated that methanol and ethanol had a slightly larger Sauter mean diameter (SMD) than that of gasoline with swirl injector. The SMD profile of methanol coincided well with that of ethanol under low back-pressure ambient conditions, but displayed a slightly larger value under high back-pressure due to fuel evaporation. Numerical simulation could successfully demonstrate the spray characteristics of high-pressure swirl injector for methanol and ethanol fuels.

关键词: low back-pressure     diameter     initial spray     hollow     middle    

Low-carbohydrate diets lead to greater weight loss and better glucose homeostasis than exercise: a randomized

《医学前沿(英文)》 2021年 第15卷 第3期   页码 460-471 doi: 10.1007/s11684-021-0861-6

摘要: Lifestyle interventions, including dietary adjustments and exercise, are important for obesity management. This study enrolled adults with overweight or obesity to explore whether either low-carbohydrate diet (LCD) or exercise is more effective in metabolism improvement. Forty-five eligible subjects were randomly divided into an LCD group (n=22) and an exercise group (EX, n=23). The subjects either adopted LCD (carbohydrate intake<50 g/day) or performed moderate-to-vigorous exercise (≥30 min/day) for 3 weeks. After the interventions, LCD led to a larger weight loss than EX (−3.56±0.37 kg vs. −1.24±0.39 kg, P<0.001), as well as a larger reduction in fat mass (−2.10±0.18 kg vs. −1.25±0.24 kg, P=0.007) and waist circumference (−5.25±0.52 cm vs. −3.45±0.38 cm, P=0.008). Both interventions reduced visceral and subcutaneous fat and improved liver steatosis and insulin resistance. Triglycerides decreased in both two groups, whereas low-density lipoprotein cholesterol increased in the LCD group but decreased in the EX group. Various glycemic parameters, including serum glycated albumin, mean sensor glucose, coefficient of variability (CV), and largest amplitude of glycemic excursions, substantially declined in the LCD group. Only CV slightly decreased after exercise. This pilot study suggested that the effects of LCD and exercise are similar in alleviating liver steatosis and insulin resistance. Compared with exercise, LCD might be more efficient for weight loss and glucose homeostasis in people with obesity.

关键词: low-carbohydrate diet     obesity     nonalcoholic fatty liver disease     continuous glucose monitoring     mean sensor glucose    

Novel technologies for the lost foam casting process

Wenming JIANG, Zitian FAN

《机械工程前沿(英文)》 2018年 第13卷 第1期   页码 37-47 doi: 10.1007/s11465-018-0473-2

摘要:

Lost foam casting (LFC) is a green precision casting process categorized as a near net forming technology. Yet, despite its popularity, it still suffers from some technological problems, such as poor filling ability of the castings, coarse and non-dense microstructure, low mechanical properties for the Al and Mg LFC processes, and defective carburization for the low carbon steel LFC process. These drawbacks restrict the development and widespread application of the LFC process. To solve these problems, the present study developed several novel LFC technologies, namely, LFC technologies under vacuum and low pressure, vibration solidification, and pressure solidification conditions; expendable shell casting techno- logy; and preparation technology of bimetallic castings based on the LFC process. The results showed that the LFC under vacuum and low pressure evidently improved the filling ability and solved the oxidization problem of the alloys, which is suitable for producing complex and thin-wall castings. The vibration and pressure solidifications increased the compactness of the castings and refined the microstructure, significantly improving the mechanical properties of the castings. The expendable shell casting technology could solve the pore, carburization, and inclusion defects of the traditional LFC method, obtaining castings with acceptable surface quality. Moreover, the Al/Mg and Al/Al bimetallic castings with acceptable metallurgical bonding were successfully fabricated using the LFC process. These proposed novel LFC technologies can solve the current technological issues and promote the technological progress of the LFC process.

关键词: LFC under vacuum and low pressure     vibration solidification     pressure solidification     expendable shell casting     bimetallic castings    

Separation of

Wei Hou, Qingjun Zhang, Aiwu Zeng

《化学科学与工程前沿(英文)》 2021年 第15卷 第5期   页码 1169-1184 doi: 10.1007/s11705-020-2018-6

摘要: In this study, vapor recompression and heat integration assisted distillation arrangements with either the low or high pressure in the reflux drum are proposed to reduce and/or eliminate the application of the costly refrigerant for the separation of -heptane and isobutanol mixture. The high-pressure arrangement with vapor recompression and heat integration is the most attractive among these four intensified configurations since it can reduce total annual cost by 18.10%, CO emissions by 75.01% based on natural gas (78.78% based on heavy oil fuel), and second-law efficiency by 61.20% compared to a conventional refrigerated distillation system. Furthermore, exergy destruction in each component is calculated for the heat integration configurations and is shown in pie diagrams. The results demonstrate that the high-pressure configuration presents unique advantages in terms of thermodynamic efficiency compared to the low-pressure case. In addition, dynamic control investigation is performed for the economically efficient arrangement and good product compositions are well controlled through a dual-point temperature control strategy with almost negligible product offsets and quick process responses when addressing 20% step changes in production rate and feed composition. Note that there are no composition measurement loops in our developed control schemes.

关键词: n-heptane/isobutanol     vapor recompression     heat integration     low and/or high-pressure options    

油气田监测高性能微传感器及数字化系统

赵玉龙,牛 喆,周冠武,赵立波,蒋庄德

《中国工程科学》 2013年 第15卷 第1期   页码 99-105

摘要:

针对油气田特殊环境要求,介绍了一种高温高压传感器芯片的设计及加工制造方法,并研发了相关的高性能数字变送系统。所设计的高温高压传感器芯片解决了传统压阻式传感器在高温高压环境下的热稳定性问题,通过数字补偿技术进一步提升了其系统的线性度与精度,并针对油气田监测环境扩展了其相关外围设备。同时,为了适应油气田管监测理要求,设计了相关无线传感网络,以确保其工业生产的高效运行和有效控制。通过具体实验测试数据,验证了该油气田监测高性能微传感器及数字化系统的高精度及高可靠性,该系统的精度达到0.2 % FS及以上,达到世界先进水平,对国内的石化工业发展有着非常重要的意义。

关键词: 高温高压传感器芯片     高性能数字变送系统     数字补偿技术     无线传感网络     高精度    

Experimental study of wind loads on gable roofs of low-rise buildings with overhangs

Peng HUANG, Ling TAO, Ming GU, Yong QUAN

《结构与土木工程前沿(英文)》 2018年 第12卷 第3期   页码 300-317 doi: 10.1007/s11709-018-0449-7

摘要:

Gable roofs with overhangs (eaves) are the common constructions of low-rise buildings on the southeastern coast of China, and they were vulnerable to typhoons from experience. The wind pressure distributions on gable roofs of low-rise buildings are investigated by a series of wind tunnel tests which consist of 99 test cases with various roof pitches, height-depth ratios and width-depth ratios. The block pressure coefficients and worst negative (block) pressure coefficients on different roof regions of low-rise buildings are proposed for the main structure and building envelope, respectively. The effects of roof pitch, height-depth ratio, and width-depth ratio on the pressure coefficients of each region are analyzed in detail. In addition, the pressure coefficients on the roofs for the main structure and building envelope are fitted according to roof pitch, height-depth ratio and width-depth ratio of the low-rise building. Meanwhile, the rationality of the fitting formulas is verified by comparing the fitting results with the codes of different countries. Lastly, the block pressure coefficients and worst negative pressure coefficients are recommended to guide the design of low-rise buildings in typhoon area and act as references for the future’s modification of wind load codes.

关键词: low-rise building     gable roof     wind loads     wind tunnel test     block pressure coefficient     load code    

标题 作者 时间 类型 操作

Piezoresistive pressure sensor with high sensitivity for medical application using peninsula-island structure

Tingzhong XU, Hongyan WANG, Yong XIA, Zhiming ZHAO, Mimi HUANG, Jiuhong WANG, Libo ZHAO, Yulong ZHAO, Zhuangde JIANG

期刊论文

Theoretical study of failure in composite pressure vessels subjected to low-velocity impact and internalpressure

Roham RAFIEE, Hossein RASHEDI, Shiva REZAEE

期刊论文

Numerical investigation and optimal design of fiber Bragg grating based wind pressure sensor

Xiangjie WANG, Danhui DAN, Rong XIAO, Xingfei YAN

期刊论文

Low crosstalk switch unit for dense piezoelectric sensor networks

Lei QIU, Shenfang YUAN,

期刊论文

Ionic strength directed self-assembled polyelectrolyte single-bilayer membrane for low-pressure nanofiltration

期刊论文

Using mRNA to investigate the effect of low-pressure ultraviolet disinfection on the viability of

Chao Yang, Wenjun Sun, Xiuwei Ao

期刊论文

Study of the robustness of a low-temperature dual-pressure process for removal of CO

Stefania Moioli, Laura A. Pellegrini, Paolo Vergani, Fabio Brignoli

期刊论文

Shrink-induced graphene sensor for alpha-fetoprotein detection with low-cost self-assembly and label-free

Shota SANDO, Bo ZHANG, Tianhong CUI

期刊论文

Catalytic ozonation of reactive red X-3B in aqueous solution under low pressure: decolorization and OH

Hong SUN,Min SUN,Yaobin ZHANG,Xie QUAN

期刊论文

Spray characteristics of high-pressure swirl injector fueled with alcohol

WANG Xibin, CHEN Wansheng, GAO Jian, JIANG Deming, HUANG Zuohua

期刊论文

Low-carbohydrate diets lead to greater weight loss and better glucose homeostasis than exercise: a randomized

期刊论文

Novel technologies for the lost foam casting process

Wenming JIANG, Zitian FAN

期刊论文

Separation of

Wei Hou, Qingjun Zhang, Aiwu Zeng

期刊论文

油气田监测高性能微传感器及数字化系统

赵玉龙,牛 喆,周冠武,赵立波,蒋庄德

期刊论文

Experimental study of wind loads on gable roofs of low-rise buildings with overhangs

Peng HUANG, Ling TAO, Ming GU, Yong QUAN

期刊论文