Effects of molecular structure of polymeric surfactant on its physico-chemical properties, percolation and enhanced oil recovery

Yiqiang Li,Xin Chen,Zheyu Liu,Ruina Liu,Wentao Liu,Han Zhang 한국공업화학회 2021 Journal of Industrial and Engineering Chemistry Vol.101 No.-

Polymeric surfactant can simultaneously thicken aquous phase and reduce water–oil interfacial tension(IFT), which makes it present a great application prospect in the oilfield taword enhanced oil recovery(EOR). There are two kinds of polymeric surfactant with different molecular structures are commonlyused to realize the salt resistance, thermal endurance and shear resistance. However, the influence ofthe molecular structure of polymeric surfactant on their properties related on EOR are not well understood. In the work, we synthesized two kinds of polymeric surfactants with different molecular structurewhich respectively named intermolecular association molecule (IAM) and rigid chain molecule (RCM). Their physico-chemical properties, porous media transportation and EOR are compared with a series ofexperiments. It is found that the hydrodynamic characteristic sizes and retention of IAM are higher thanthose of RCM via the membrane filtration test and nuclear magnetic resonance (NMR) scan. These featuresmake IAM have a larger resistance factor and residual resistance factor than RCM and hydrolyzedpolyacrylamide (HPAM) in the same viscosity. Compare to HPAM with shear thinning, RCM presents aNewtonian fluid region and IAM presents a shear thickening region when the shear rate is lower than1 s 1. The spatial structure of IAM can pack oil drop into its network, which make it easy to form oilin-water-in-oil (O/W/O) emulsions. Moreover, the concentration and water–oil ratio (WOR) rarely affectthe stability of IAM emulsions once the intermolecular association generated. The increamental oil recoveryfactor of IAM is 17.5% after water flooding in the three-layer core flooding experiments with the permeabilityof 500 mD, 1500 mD and 3000 mD at 55℃, which is higher than that of 14.5% for RCM and11.4% for HPAM.

Cellulose Nanocrystals and Polyanionic Cellulose as Additives in Bentonite Water-Based Drilling Fluids: Rheological Modeling and Filtration Mechanisms

Li, Mei-Chun,Wu, Qinglin,Song, Kunlin,De Hoop, Corneils F.,Lee, Sunyoung,Qing, Yan,Wu, Yiqiang American Chemical Society 2016 INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH - Vol.55 No.1

<P>This research aims to develop low cost, sustainable, environmentally friendly, and high performance water-based drilling fluids (WDFs) using bentonite (BT), polyanionic cellulose (PAC), and cellulose nanocrystals (CNCs). The effect of concentration of BT, PAC, and CNCs on the rheological and filtration properties of PAC/CNC/BT-WDFs was investigated. Eight empirical rheological models were applied to fit quantitatively the fluid properties. Results showed that the presence of PAC, CNCs, and BT improved the rheological and filtration properties of the WDFs. Among the eight empirical rheological models, the Sisko model performed the best in simulating the rheological behavior of the fluids. At the same concentration level of PAC and CNCs, CNCs had more impact on the rheological properties, whereas PAC had more influence on the filtration property. The incorporation of PAC resulted in very low permeable filter cakes, leading to the excellent filtration property. The combined use of PAC and CNCs yielded better rheological and filtration properties.</P>

Numerical Study on the Influence of the Width of the SBM Disc Cutter on Rock Breaking

Yiqiang Kang,Yang-shuai Shu,Li-yun Yang,Ren-shu Yang,Yi-chuan Xu,Zheng Xie,Ke-yao Ren 대한토목학회 2023 KSCE Journal of Civil Engineering Vol.27 No.9

The study of the rock-breaking pattern of shaft boring machine (SBM) cutters is the basis for cutter design. In order to reveal the influence of the cutter blade width on the rock-breaking effect, this study established a discrete-continuous coupled rock mass numerical model. By setting different blade widths and types, the variation patterns of cutter forces, rock-breaking area, and specific energy with the blade width were revealed. The influence of the blade type on the breaking coefficient was further quantified according to the fractal dimension. The results show that under the cutting action, the rock mass can be divided into dense core, fractured zone, and elastic deformation zone, with the fractured zones mainly located on the lower side of the cutter's central axis. As the width of the cutter increases, the cutter penetration force and side force increase linearly with the increase in blade width, the breaking area increases and then tends to remain constant, the specific energy decreases first and then increases, and the rock fragmentation factor increases linearly. After scaling the width of the flat blade up to 18 mm and the arc blade to 24 mm, further increase in the blade width does not improve the breaking efficiency but only results in a smaller slag granularity.

Regulation of local alternating electric fi elds on synaptic plasticity in brain tissue

Chi Zhang,Yiqiang Li,Li Yang,Hongwei Zhao 대한의용생체공학회 2023 Biomedical Engineering Letters (BMEL) Vol.13 No.3

Purpose External electric fields can regulate the neural network and change the excitability of the in-vivo cerebral cortex. Here, to prove the effect of alternating electric fields on the synaptic plasticity of ex-vivo tissues, the regular changes in thesynaptic structure under alternating electric fields were studied. Methods This study applied alternating electric fields with a peak voltage of 20 V and frequencies of 5, 20, 50, and 80 Hzto the porcine cerebral cortex. Relying on transmission electron microscopy (TEM), the ultrastructure of synapses wasobserved, and the curvature radius of post-synaptic density (PSD) and the synaptic gap distance was quantified. Results The results indicated that under alternating electric fields, the average synaptic curvature of the PSD decreased by30–59% with increasing frequency, and the average synaptic gap distance became narrower. Conclusion In ex-vivo brain tissue, synaptic plasticity can be regulated by alternating electric fields of different frequencies. This study can provide reference data for the storage and regulation of ex-vivo organs, as well as comparable data for in-vivostudies.

Effects of Dietary Coconut Oil as a Medium-chain Fatty Acid Source on Performance, Carcass Composition and Serum Lipids in Male Broilers

Wang, Jianhong,Wang, Xiaoxiao,Li, Juntao,Chen, Yiqiang,Yang, Wenjun,Zhang, Liying Asian Australasian Association of Animal Productio 2015 Animal Bioscience Vol.28 No.2

This study was conducted to investigate the effects of dietary coconut oil as a medium-chain fatty acid (MCFA) source on performance, carcass composition and serum lipids in male broilers. A total of 540, one-day-old, male Arbor Acres broilers were randomly allotted to 1 of 5 treatments with each treatment being applied to 6 replicates of 18 chicks. The basal diet (i.e., R0) was based on corn and soybean meal and was supplemented with 1.5% soybean oil during the starter phase (d 0 to 21) and 3.0% soybean oil during the grower phase (d 22 to 42). Four experimental diets were formulated by replacing 25%, 50%, 75%, or 100% of the soybean oil with coconut oil (i.e., R25, R50, R75, and R100). Soybean oil and coconut oil were used as sources of long-chain fatty acid and MCFA, respectively. The feeding trial showed that dietary coconut oil had no effect on weight gain, feed intake or feed conversion. On d 42, serum levels of total cholesterol, low-density lipoprotein cholesterol, and low-density lipoprotein/high-density lipoprotein cholesterol were linearly decreased as the coconut oil level increased (p<0.01). Lipoprotein lipase, hepatic lipase, and total lipase activities were linearly increased as the coconut oil level increased (p<0.01). Abdominal fat weight/eviscerated weight (p = 0.05), intermuscular fat width (p<0.01) and subcutaneous fat thickness (p<0.01) showed a significant quadratic relationship, with the lowest value at R75. These results indicated that replacement of 75% of the soybean oil in diets with coconut oil is the optimum level to reduce fat deposition and favorably affect lipid profiles without impairing performance in broilers.

Low-speed rolling bearing fault diagnosis based on EMD denoising and parameter estimate with alpha stable distribution

Qing Xiong,Yanhai Xu,Yiqiang Peng,Weihua Zhang,Yongjian Li,Lan Tang 대한기계학회 2017 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.31 No.4

When low-speed rolling bearings fail, it is hard to diagnose the extent of their damage. We developed a test rig to simulate the lowspeed rolling bearing operating condition, where bearings with various fault states are installed on the test wheelset and subjected to the same external loading condition. The collected bearing box acceleration time histories are processed with the Empirical mode decomposition (EMD) method combined with kurtosis criterion to filter the trend and noise components. Five characteristic parameters of Alpha stable distribution (ASD) are identified by fitting the ASD distribution to the vibration acceleration signals and computing the Probability density function (PDF). To highlight the advantage of ASD method in feature extraction, kurtosis also has be calculated. Through sensitivity and stability analysis of the six parameters and utilization of Least squares support vectors machine (LSSVM) with Particle swarm optimization (PSO), three most sensitive and stable feature parameters including the characteristic exponent a, the scale factor g and the peak value of the PDF h are located and applied to evaluate the low-speed rolling bearings’ damage position and damage extent. The proposed method was validated by test data, and the results demonstrated that the ASD characteristics combined with PSO-LSSVM can not only achieve fault diagnosis of low-speed rolling bearings' damage position and damage extent, but also have better diagnosis accuracy and operational efficiency than other methods.

Comparative digestibility of nutrients and amino acids in high-fiber diets fed to crossbred barrows of Duroc boars crossed with Berkshire×Jiaxing and Landrace×Yorkshire

Zhao, Jinbiao,Wang, Qiuyun,Liu, Ling,Chen, Yiqiang,Jin, Aiming,Liu, Guoliang,Li, Kaizhen,Li, Defa,Lai, Changhua Asian Australasian Association of Animal Productio 2018 Animal Bioscience Vol.31 No.5

Objective: This experiment was conducted to determine the differences in the apparent ileal (AID) and total tract digestibility (ATTD) of nutrients and indispensable amino acids (IAA) in high-fiber diets with wheat middlings, rice bran or alfalfa meal fed to Duroc${\times}$(Landrace${\times}$Yorkshire) (DLY) and Duroc${\times}$ (Berkshire${\times}$Jiaxing) (DBJ) growing barrows. Methods: Eighteen DLY and 18 DBJ growing barrows were randomly allotted to a $2{\times}3$ factorial arrangement involving 2 crossbreeds and 3 high-fiber diets. The experiment lasted 15 d with 10 d for diets adaptation, 3 d for feces collection and 2 d for digesta collection. Three diets were based on corn and soybean meal with 25% wheat middlings, rice bran and alfalfa meal respectively. Results: DBJ had a greater (p<0.05) AID of isoleucine, leucine, lysine, phenylalanine and valine and a lower (p<0.05) AID of methionine than DLY. The hindgut disappearance of acid detergent fiber for DBJ was greater (p<0.05) than DLY. The ATTD of gross energy, dry matter, organic matter, neutral detergent fiber and acid detergent fiber in wheat middlings diet were greater (p<0.05) than in rice bran and alfalfa meal diets. The hindgut disappearance of neutral detergent fiber and acid detergent fiber in wheat middlings diet or rice bran diet were the highest or lowest (p<0.05), and those of alfalfa meal diet were the middle. Barrows fed rice bran diet had a greater (p<0.05) hindgut disappearance of gross energy, dry matter and organic matter and lower hindgut disappearance of neutral detergent fiber and acid detergent fiber than barrows fed alfalfa meal diet Conclusion: DBJ growing barrows showed a significant higher digestibility of fiber in the hindgut and most IAA in the small intestine compared with DLY barrows. The digestibilities of chemical constituents and IAA were affected by the diets formulated with different fiber sources.

Mechanical behavior of stud shear connectors embedded in HFRC

Yu-Liang He,Xu-Dong Wu,Yiqiang Xiang,Yu-Hang Wang,Li-Si Liu,Zhi-Hai He 국제구조공학회 2017 Steel and Composite Structures, An International J Vol.24 No.2

Hybrid-fiber reinforced concrete (HFRC) may provide much higher tensile and flexural strengths, tensile ductility, and flexural toughness than normal concrete (NC). HFRC slab has outstanding advantages for use as a composite bridge potential deck slab owing to higher tensile strength, ductility and crack resistance. However, there is little information on shear connector associated with HFRC slabs. To investigate the mechanical behavior of the stud shear connectors embedded in HFRC slab, 14 push-out tests (five batches) in HFRC and NC were conducted. It was found that the stud shear connector embedded in HFRC had a better ductility, higher stiffness and a slightly larger shear bearing capacity than those in NC. The experimentally obtained ultimate resistances of the stud shear connectors were also compared against the equations provided by GB50017 2003, ACI 318-112011, AISC 2011, AASHTO LRFD 2010, PCI 2004, and EN 1994-1-1 (2004), and an empirical equation to predict the ultimate shear connector resistance considering the effect of the HFRC slabs was proposed and validated by the experimental data. Curve fitting was performed to find fitting parameters for all tested specimens and idealized load-slip models were obtained for the specimens with HFRC slabs.

ESVD: An Integrated Energy Scalable Framework for Low-Power Video Decoding Systems

Ji, Wen,Chen, Min,Ge, Xiaohu,Li, Peng,Chen, Yiqiang Hindawi Publishing Corporation 2010 Eurasip Journal on Wireless Communications and Net Vol.2010 No.-

<P>Video applications using mobile wireless devices are a challenging task due to the limited capacity of batteries. The higher complex functionality of video decoding needs high resource requirements. Thus, power efficient control has become more critical design with devices integrating complex video processing techniques. Previous works on power efficient control in video decoding systems often aim at the low complexity design and not explicitly consider the scalable impact of subfunctions in decoding process, and seldom consider the relationship with the features of compressed video date. This paper is dedicated to developing an energy-scalable video decoding (ESVD) strategy for energy-limited mobile terminals. First, ESVE can dynamically adapt the variable energy resources due to the device aware technique. Second, ESVD combines the decoder control with decoded data, through classifying the data into different partition profiles according to its characteristics. Third, it introduces utility theoretical analysis during the resource allocation process, so as to maximize the resource utilization. Finally, it adapts the energy resource as different energy budget and generates the scalable video decoding output under energy-limited systems. Experimental results demonstrate the efficiency of the proposed approach.</P>

Effects of Dietary Coconut Oil as a Medium-chain Fatty Acid Source on Performance, Carcass Composition and Serum Lipids in Male Broilers

Jianhong Wang,Xiaoxiao Wang,Juntao Li,Yiqiang Chen,Wenjun Yang,Liying Zhang 아세아·태평양축산학회 2015 Animal Bioscience Vol.28 No.2

This study was conducted to investigate the effects of dietary coconut oil as a medium-chain fatty acid (MCFA) source on performance, carcass composition and serum lipids in male broilers. A total of 540, one-day-old, male Arbor Acres broilers were randomly allotted to 1 of 5 treatments with each treatment being applied to 6 replicates of 18 chicks. The basal diet (i.e., R0) was based on corn and soybean meal and was supplemented with 1.5% soybean oil during the starter phase (d 0 to 21) and 3.0% soybean oil during the grower phase (d 22 to 42). Four experimental diets were formulated by replacing 25%, 50%, 75%, or 100% of the soybean oil with coconut oil (i.e., R25, R50, R75, and R100). Soybean oil and coconut oil were used as sources of long-chain fatty acid and MCFA, respectively. The feeding trial showed that dietary coconut oil had no effect on weight gain, feed intake or feed conversion. On d 42, serum levels of total cholesterol, low-density lipoprotein cholesterol, and low-density lipoprotein/high-density lipoprotein cholesterol were linearly decreased as the coconut oil level increased (p<0.01). Lipoprotein lipase, hepatic lipase, and total lipase activities were linearly increased as the coconut oil level increased (p<0.01). Abdominal fat weight/eviscerated weight (p = 0.05), intermuscular fat width (p<0.01) and subcutaneous fat thickness (p<0.01) showed a significant quadratic relationship, with the lowest value at R75. These results indicated that replacement of 75% of the soybean oil in diets with coconut oil is the optimum level to reduce fat deposition and favorably affect lipid profiles without impairing performance in broilers.