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Copyright of Science & Technology of Food Industry is the property of Science & Technology of Food Industry Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Reviews of Geophysics & Planetary Physics is the property of Editorial Office of Reviews of Geophysics & Planetary Physics and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

BACKGROUND: The anterior cruciate ligament has unique nonlinear mechanical properties under a complex physiological loading environment. Elastin is an important contributor to the mechanical properties of the anterior cruciate ligament, but its mechanical response to the anterior cruciate ligament under axial tension is not clear. OBJECTIVE: To quantitatively analyze the effect of elastin on the tensile mechanical response of the anterior cruciate ligament. METHODS: Elastase solution and control buffer were prepared. The porcine anterior cruciate ligament samples were prepared into small-size samples and randomly soaked in 0, 0.1, 1.0, 2.0, 5.0, and 10.0 U/mL elastase solution for 6 hours, and other small samples of the same size were soaked in 2 U/mL elastase solution for 0, 1, 3, 6, 9, and 12 hours. To determine suitable soaking conditions for elastin-targeted enzymes and verify the digestive effect, histological staining was used to compare the effects of enzyme treatment on tissue structure and composition. The ligament samples were randomly divided into elastase-treated group and PBS group, and immersed in 2 U/mL elastase solution and PBS buffer for 6 hours, respectively. A mechanical tensile test was performed before and after immersion. RESULTS AND CONCLUSION: (1) The biochemical results showed that being treated in 2 U/mL elastase solution for 6 hours could reduce the elastin content by 31.1%, and had no significant effect on other mechanical-related components in the tissue. (2) The histological results showed that elastase was able to penetrate the tissue, and the loose degree of tissue increased after treatment. (3) In the mechanical results before and after treatment, the mechanical properties of the PBS group decreased significantly, only the low-tension elastic modulus increased significantly and the initial length increased significantly in the elastase-treated group. (4) The intergroup comparison results showed that there was no significant difference between the two groups in pre-treatment, but the low-tension elastic modulus, initial slopes, saturated slopes, and initial length of the elastase-treated group after treatment were significantly higher than those in the PBS group. (5) These results suggest that elastin degradation significantly affects the biomechanical properties of the anterior cruciate ligament and further complements our understanding of the structure-function relationship of the anterior cruciate ligament. [ABSTRACT FROM AUTHOR]

The improvement of computing power provides a support for finite element simulation analysis, which can solve more complex structures and nonlinear problems more efficiently. In this study, based on the finite element simulation analysis technology, the complex mechanical properties of Mn-Cu alloy are simulated. Prony series constitutive model and parallel rheological constitutive model are respectively adopted to simulate the stress relaxation test of Mn-Cu alloy under different deformation conditions. The stress relaxation experimental data are extracted and converted into the corresponding model parameters and the finite element simulation calculation is carried out. The simulation model parameters which can accurately describe the nonlinear mechanical properties of Mn-Cu alloy are obtained. By comparing the simulation and experimental results, it is concluded that the parallel rheological framework can more accurately characterize the stress relaxation behavior of Mn-Cu alloy. Under different initial strain conditions, the relative error of the simulation results and the test results under corresponding working conditions is less than 1%. Compared with Prony series constitutive model, parallel rheological framework is more suitable for the simulation of Mn-Cu alloy under complex working conditions. [ABSTRACT FROM AUTHOR]

Copyright of Shipin Kexue/ Food Science is the property of Food Science Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Shipin Kexue/ Food Science is the property of Food Science Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Objective: The aggregation behavior of silk fibroin under specific conditions can influence its kinetic behavior and viscoelastic properties, thereby affecting biological properties of silk fibroin materials. Therefore, this study systematically investigated the self-assembly aggregation behavior of silk fibroin and explored the conditions for enhancing its mechanical performance and biological properties. Methods: Regenerated silk fibroin was extracted and prepared from domestic silkworm cocoons, and the optimal assembly conditions were determined through turbidity experiments. Rheological experiments were conducted to study the influence of Na+ on the kinetic behavior and viscoelastic properties of silk fibroin solutions. Cell proliferation experiments were carried out to investigate the biological properties of silk fibroin. Results: The extracted regenerated silk fibroin primarily exhibited a random coiled structure. The optimal in vitro self-assembly conditions involved assembly of a 4 mg/mL solution at 70 ℃ for 6 hours. The addition of Ca2+ to the silk fibroin solution inhibited in vitro self-assembly, while the addition of Na+ accelerated the assembly rate and increased the degree of assembly. Furthermore, with increasing Na+ concentration, the gel strength of silk fibroin gradually increased, leading to a more stable gel network. Cell proliferation experiments demonstrated that the solution of regenerated silk fibroin was more conducive to cell growth and proliferation than its self-assembled fibers. Conclusion: The concentration, temperature, assembly time, and ions all have an impact on the in vitro self-assembly aggregation behavior of silk fibroin. This study provides preliminary research on the self-assembly aggregation conditions and biological properties of silk fibroin, offering experimental basis for improving the performance of silk fibroin as a food packaging material.

As a result of significant advances in geophysics, we have developed a rich arsenal of geophysical methods to infer the internal structure of the Earth. However, the method we could use to infer the internal structure of celestial bodies other than the Earth are still very limited, often relying on geodetic data from orbital probes, landers and astronomical observations. Among these geodetic method, solid tides are of great importance for the study of the celestial bodies' internal structure. Solid tidal deformation and the tidal dissipation provide key information about the internal structure of the rocky celestial bodies, especially the deep structure which contains core-mantle boundary and core. In this paper, we present a comprehensive overview of the research of the deep structure of rocky celestial bodies using solid tidal parameters, including tidal Love numbers and tidal quality factor. First, the basic theory of solid tides, tidal parameters, and viscoelastic models are introduced, and the relationship between the internal structural parameters of the celestial bodies and their solid tidal response is established. This is followed by a review and summary of existing work using solid tide parameters to study the internal structure of the rocky celestial bodies like Mercury, Venus, Mars, and the Moon. Examples include the study of the viscoelastic structure at the base of the lunar mantle using tidal parameters, and the use of tidal parameters to improve the uncertainty of the Martian core radius demonstrate that using solid tidal parameters is an effective method of constraining the deep structure of the celestial bodies. We further provide the contribution of high-precision observations to be acquired by future missions to the study of internal structure. However, there still are some problems in study the internal structure of celestial bodies by solid tidal parameters. For instance, the variability of dissipation strength between different viscoelastic models, the mismatch between short-period experimental data and macroscopic long-period theoretical calculations of viscoelastic models, and so on. We also discuss and analyzes these problems and provides a vision of future research direction.

Magnetic resonance elastography (MRE) is a method to estimate biomechanical properties of soft tissues by recording shear wave propagation using MR imaging. The wave excitation is produced by an external actuator and the properties are inversely calculated based on the wave equation. Biomechanical properties of brain tissue, especially the viscoelastic properties, are closely related to the growth, aging, and disease of brain. This review first introduces the theoretical background of MRE, followed by the physical meaning of the viscoelastic parameters and wave equations used for inversion. Scanning protocols for MRE, along with a specific example focusing on brain MRE, are also described. The paper presents various clinical applications of brain MRE, with a specific emphasis on brain tumors and neurodegenerative diseases. The application of viscoelastic properties as biomarkers in fundamental scientific research, disease diagnosis, and prognosis is discussed. We further highlight the current trends in brain MRE research covering both technical and clinical aspects, providing a reference for future neuroscience research and clinical applications.

It is worth studying how to strike a balance between the magnetorheological effect and sedimentation stability in magnetic nanofluids, and the use of larger nanoparticles has been identified as a promising solution. Fe3O4 magnetic particles with a size of approximately 25 nm were synthesized using a controlled chemical co-precipitation method, and their phase composition and magnetic properties were characterized. Magnetic nanofluids were prepared using myristic acid as surfactant and RP4350 aviation hydraulic oil as dispersed phase, which exhibited prolonged stability under strong magnetic fields, with applicable temperatures ranging from -35 ℃ to 95 ℃. The variations in magnetorheological properties with magnetic field strength and temperature were investigated. The results reveal that under the influence of low temperatures and strong magnetic fields, the magnetic nanofluids exhibited significantly higher yield stress, reaching a maximum of 0.16 kPa. Even after yielding, the samples displayed stronger magnetoviscous effect. Dynamic rheological characteristics of magnetic nanofluids were examined using amplitude sweep measurements. The increase in magnetic field strength and the decrease in temperature can effectively enhance the shear resistance of the nanomagnetic fluid, which leads to the elevation of the storage modulus. Furthermore, the linear viscoelastic (LVE) region and the crossover point of the storage modulus and loss modulus also shift towards higher strain amplitudes. These findings contribute to the research on magnetic nanofluids prepared with larger particles and provide guidance for their applications over a wider temperature range. [ABSTRACT FROM AUTHOR]

Copyright of Chinese Journal of Computational Mechanics / Jisuan Lixue Xuebao is the property of Chinese Journal of Computational Mechanics Editorial Office, Dalian University of Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Chinese Journal of Applied Mechanics is the property of Chinese Journal of Applied Mechanics Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This study investigated the effects of different durations of ultrasound treatment (0, 10, 20, 30, 40 and 50 min) on the gelatinization, rheological properties, crystal structure, short-range ordered structure, and microstructure of lotus root starch (LS). The results showed that the molecular chain swelled and entanglement increased after ultrasonic treatment, and the gelatinization viscosity increased up to (6 059 ± 31) mPa·s. Cracks, and collapses and holes appeared on the surface of starch particles, which promoted the entrance of water molecules and increase the viscoelasticity. Ultrasound treatment destroyed the α-1,6-glycosidic bonds of starch molecules, and broke some branches to form short starch chains, which were rearranged into ordered structures. The number of short-range ordered structures increased, and the R1 047/1 022 ratio increased by 3.20%. Short-time ultrasonic treatment (30 min) enhanced the interaction between starch molecules, making the double helix structure more ordered and compact and increasing the Tp and ΔH by 11.09% and 89.21%, respectively. Long-time ultrasonic treatment (40–50 min) was not conducive to the formation of ordered structures. The results of this study can provide a theoretical basis for the application of ultrasonic in regulating the physicochemical properties and multi-scale structure of starch.

Copyright of Shipin Kexue/ Food Science is the property of Food Science Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of China Plastics / Zhongguo Suliao is the property of Journal Office of CHINA PLASTICS and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Railway Standard Design is the property of Railway Standard Design Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of China Condiment is the property of China Condiment and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The development effects of heavy oil reservoirs after water flooding become poor due to the serious emulsification of produced liquid and reduction of formation fluidity in Block Jin17 of Shengli Oilfield. Therefore， the emulsification characteristics of heavy oil and water were studied through emulsification state analysis， viscosity， and rheology testing， oil-water interfacial tension （IFT） testing， etc.， and the flow characteristics of emulsified heavy oil were analyzed. Then， the re-emulsification characteristics of emulsified heavy oil were studied by analyzing the emulsification state， droplet size， viscosity， and viscoelasticity of emulsions formed by emulsification oil flooding agent and W/O emulsion. Finally， the re-emulsification mechanisms of emulsified heavy oil were analyzed， and the idea of emulsification oil flooding method was provided. The results show that emulsification has a serious effect on the viscosity of heavy oil emulsions. Under the reservoir temperature of 60 °C， the viscosity， viscosity modulus， and IFT of W/O emulsions with water content of 60% are 11.9， 13.49， and 2.49 times that of dehydrated heavy oil， respectively. Moreover， the fluidity of W/O emulsions in the porous media is seriously restricted due to its stronger non-Newtonian characteristics， the viscosity increased exponentially， the viscous modulus increased significantly， and IFT increased rapidly when the water content is higher than 40%. W/O/W multiple emulsions are formed when emulsified heavy oil and emulsification oil flooding agents are re-emulsified. Moreover， the droplet size， viscosity， and viscoelasticity of the emulsions increase with the increment of initial water content in W/O emulsion. When the initial water content of W/O emulsion is 60%， the droplet sizes of emulsions formed by emulsification oil flooding agents LPA， HPF， and SDS and W/O emulsion are 91.3， 40.6， and 27.5 μm， respectively. Compared with the emulsions formed with dehydrated heavy oil， the droplet sizes are 7.9， 4.0， and 2.2 times， respectively. This indicates that the emulsification of formation water/injection water and heavy oil has a great influence on enhanced oil recovery of heavy oil by emulsification oil flooding agents. Therefore， strengthening the ability of emulsification oil flooding systems to penetrate oil film and replace the adsorption of active substances in heavy oil on the oil-water interface is the focus of subsequent research and development of emulsification oil flooding systems and construction method design.

Copyright of China Rural Water & Hydropower is the property of China Rural Water & Hydropower Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Chinese Journal of Explosives & Propellants is the property of Chinese Journal of Explosives & Propellants Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Petroleum Geology & Recovery Efficiency is the property of Petroleum Geology & Recovery Efficiency and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of East China University of Science & Technology is the property of Journal of East China University of Science & Technology Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Petroleum Geology & Oilfield Development in Daqing is the property of Editorial Department of Petroleum Geology & Oilfield Development in Daqing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Coal Geology & Exploration is the property of Xian Research Institute of China Coal Research Institute and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Geodesy & Geodynamics (1671-5942) is the property of Editorial Board Journal of Geodesy & Geodynamics and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of China Surfactant Detergent & Cosmetics (2097-2806) is the property of China Surfactant Detergent & Cosmetics Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In order to investigate the mechanical properties of uncured rubber, uniaxial and cyclic tensile experiments are conducted on uncured rubber at different strain rates. From the experimental results, the rate-dependent nonlinear mechanical behaviors of uncured rubber can be clearly observed. With strain rate increasing, the stress level, hysteresis and Mullins effect get enhanced, and the residual strain decreases. To characterize the nonlinear visco-elastoplastic mechanical behaviors of uncured rubber, a three-network (TN) constitutive model that contains a hyperelastic network and two nonlinear viscoplastic networks is proposed. The eight-chain model is used to characterize the hyperelastic behavior while the Bergstr?m-Boyce flow model is applied in the viscoplastic networks to capture the nonlinear viscous flow. The proposed constitutive model is implanted into the finite element software Abaqus with which, the multistep tensile relaxation test is simulated. The simulation result is satisfactorily consistent with experimental results, which verifies the effectiveness of the TN model. Finally, the simplified molding process of a tire tread is simulated, which further verifies the stability of the TN model.

Objective： This study aimed to improve the yield and gelling property of lemon pectin. Methods: Oxalic acid was used to extract pectin from lemon residue. The factors of optimal ratio of solid-liquid, pH, extraction temperature and extraction time were optimized through single factor experiments and orthogonal experiments. The purity, degree of esterification and rheological properties of the extracted lemon pectin were analyzed. The differences of gelling property between the extracted lemon pectin and two kinds of commercial high methoxyl pectins (HMP-1, HMP-2) were compared. Results: The results showed that the yield of pectin extract was 22.83%, with total galacturonic acid of 76.06% and degree of esterification of 75.94%, when the ratio of solid-liquid was 1∶20 （g/mL）, extracting pectin at pH 2.2 and 95 ℃ for 75 min. The viscosity of the extracted lemon pectin was higher than HMP-1 and HMP-2. The calcium sensitivity was between HMP-1 and HMP-2, and the temperature sensitivity was similar to HMP-2. The sol-gel transformation of the extracted lemon pectin was found at 76.55 ℃ in the calcium ion environment. Conclusion: Lemon pectin extracted by oxalic acid has good rheological and gel properties, and can be potentially used as a stabilizer in acidic milk drinks.

Copyright of Oilfield Chemistry is the property of Sichuan University, Oilfield Chemistry Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Polymer Materials Science & Engineering is the property of Sichuan University, Polymer Research Institute and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Polymer Materials Science & Engineering is the property of Sichuan University, Polymer Research Institute and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Food Research & Development is the property of Food Research & Development Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Food & Machinery is the property of Food & Machinery Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Shanghai Jiao Tong University (1006-2467) is the property of Journal of Shanghai Jiao Tong University Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Shipin Kexue/ Food Science is the property of Food Science Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Harbin Institute of Technology. Social Sciences Edition / Haerbin Gongye Daxue Xuebao. Shehui Kexue Ban is the property of Harbin Institute of Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Modern Food Science & Technology is the property of Editorial Office of Modern Food Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Chinese Institute of Food Science & Technology is the property of Journal of Chinese Institute of Food Science & Technology Periodical Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

BACKGROUND: Patellar tendon is an important structure to maintain the stability of the knee joint and exhibits unique nonlinear mechanical properties under tension, but the effect of elastin on the mechanical behavior of the patellar tendon under tensile loading is still unclear. OBJECTIVE: To study the effect of elastin on the mechanical properties of patellar tendon through targeted enzyme treatment of elastin. METHODS: (1) Thirty fresh porcine patellar tendons, weighing 40–50 mg, were evenly divided into five different elastase concentrations (0, 1, 5, 10, 20 U/mL) or incubated in elastase solutions for five different times (0, 1, 4, 6, 12 hours), and finally the elastin content was detected. (2) Patellar tendon was treated in PBS or 5 U/mL elastase for 8 hours, then Verhoeff Van Gieson (VVG) staining and Masson staining were performed. (3) Twenty fresh porcine patellar tendons were randomly divided into PBS control group and elastase-treated group. After 9 points were marked on the sample surface, the longitudinal tensile test and stress relaxation test were carried out. The displacement of the marked points was calculated by optical non-contact method for subsequent strain analysis and stress calculation. The samples were incubated in PBS or 5 U/mL elastase for 8 hours, and the same mechanical test was performed again. RESULTS AND CONCLUSION: (1) Incubating in 5 U/mL elastase for 8 hours could meet the requirements of this experiment. (2) Compared with pre-treatment, tissue tensile stress was significantly reduced in the PBS and elastase-treated groups, which were both decreased by about 40% (P < 0.001, P < 0.01). Compared with pre-treatment, the relaxation percentage after treatment increased significantly, with a difference of about 12% (P < 0.05). On the normalized average stress-time curve, the stress of elastase-treated treatment group decreased more than that of PBS group, with a difference of about 16% (P < 0.0001). (3) The above results showed that elastin played an important role in the tensile mechanical properties and viscoelastic properties of patellar tendon, further supplementing the understanding of the multiscale tendon structure-function relationships, which would be beneficial to the development and improvement of microstructure constitutive model in the future to simulate patellar tendon lesions and surgical intervention. [ABSTRACT FROM AUTHOR]

Copyright of Shipin Kexue/ Food Science is the property of Food Science Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Aiming at the problem that cationic surfactant fracturing fluid adsorbs in the formation and causes secondary damage to the reservoir, a long-chain tertiary amine（hereinafter referred to as OADA） was synthesized in the laboratory using oil diamine as raw material and Eschweiler-Clarke reaction.OADA was used as thickening agent and acetic acid as assistant.The effects of the amount of potassium chloride and the molar ratio of the main agent to acetic acid on the viscosity of the system were studied.The performance indexes of OADA clean fracturing fluid system, such as temperature resistance, shear resistance, viscoelasticity and suspended sand, were investigated.By scanning the frequency and stress of the system at room temperature, it is found that the system is mainly elastic.The system still has a viscosity of more than 25 mPa·s when it is continuously sheared at 100 ℃ and 170 s-1 for 1 h.The gel breaker has low viscosity and surface interfacial tension, and the damage rate to the core is only 5.82%,it has low damage characteristics and good compatibility with formation water. [ABSTRACT FROM AUTHOR]

The viscoelastic damping materials have temperature-frequency equivalent properties. Based on the model of Kelvin-Si fractional derivative and the viscosity equation of Vogel-Fulcher-Tammann, a time-temperature equivalent model of Kelvin-Si-TTS for the fractional derivative of viscoelastic materials was proposed, and the horizontal and vertical translation factors were derived. Thus the storage and loss modulus under Kelvin-Si fractional derivative model were obtained. The thermal dynamic mechanical analyzer was used in the frequency sweep test in (223~343) K. The Kelvin-Si-TTS model was used to obtain the translation factors at different temperatures at the reference temperature of 293 K, and the frequency of viscoelastic damping materials was extrapolated. The results showed that the translation factors of the thermal dynamic mechanical analyzer and Kelvin Si TTS models fitted well with a high degree; both translation factors were used to extrapolate the data in the temperature range of (223-343) K, and both were extrapolated to the frequency of 10-4 ~ 107, indicating that Kelvin-Si-TTS model has a good prediction ability, and the viscoelastic damping materials can be well applied in the field of vibration and noise reduction under high-frequency. The study provided a theoretical reference for the mechanism research on the dynamic properties of viscoelastic damping materials. [ABSTRACT FROM AUTHOR]

Copyright of China Plastics / Zhongguo Suliao is the property of Journal Office of CHINA PLASTICS and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Food Research & Development is the property of Food Research & Development Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Food & Machinery is the property of Food & Machinery Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In order to explore the effect of okra powder on the rheological properties of wheat dough, the thermomechanical properties, alveograph characteristics, rheofermentation and dynamic rheological properties of the mixture flour dough (the addition amount of okra powder are 0, 1%, 3%, 5%, 7% and 9%) were measured by using Mixolab, Alveolab, Rheofermentometer, rheometer and other technical methods. The results showed that the wet gluten content of the mixture flour decreased by 79.96% under the incorporation of okra powder. Furthermore, with the increasing of okra powder addition, the dough water absorption ratio increased from 63.30% to 65.90%, the dough development time and stability decreased firstly and then increased, and the protein weakening was enhanced. The pasting peak viscosity and setback decreased while the cooking stability showed no change. Meanwhile, the tenacity, extensibility and fermentation performance of dough dropped, and the maximum fermentation height Hm value decreased by 39.80%. In addition, both the storage modulus G' and the loss modulus G'' of the dough increased significantly, and the increasing of G' was dominant. In conclusion, the addition of okra powder significantly (P

A chemically cross-linkable molecular self-conjugated polymer, HCG-2， was synthesized from acrylamide， acrylic acid, 2-acrylamido-2-methylpropanesulfonic acid, functional monomers containing cross-linking sites, and cetyl dimethyl allyl ammonium chloride， and its synthesis conditions were optimized. The thixotropy and viscoelasticity of HCG-2 were investigated, and it was found that a dynamic structure could be formed between HCG-2 molecules in aqueous solution， and the surfactant sodium dodecyl sulfate could improve the strength of this structure; the relationship between temperature and the thixotropy and viscoelasticity of the system was investigated, and it was found that the interaction between HCG-2 molecular chains under the influence of the surfactant was weak and could not withstand too high temperature However, after using chemical cross-linking agents to form chemical bonds between the molecular chains, the temperature and shear resistance of the system at 180℃ could meet the requirements of the industry standard. [ABSTRACT FROM AUTHOR]

Objective Aiming at the problems of poor shear resistance of polymer and the influence of deep formation viscosity retention in conventional chemical flooding system, wormlike micelle oil displacement technology was studied. Methods Using betaine surfactant monomer (PSM), N, N-dimethylpropylene diamine and other raw materials, by two-step reaction of amidation and quaternization, the wormlike micellar surfactant for oil displacement with viscoelasticity and interfacial activity was synthesized under the conditon of reduced pressure spin drying. The molecular structure, theological properties, microstructure, shear resistance, salt resistance, interfacial tension and oil displacement characteristics of wormlike micelle were investigated. Results The structure obtained by NMR was consistent with the target product. Wormlike micelle has good viscosity increasing (mass fraction O. 30% —O. 50%, apparent viscosity 10 — 50 mPa • s, 7. 34 s-1), salt resistance (<100 000 mg/L) and the ability to reduce oil-water interfacial tension (10-2 mN/m). The core displacement experiment results showed that the wormlike micelle has stronger oil displacement ability than conventional polymer, and the FOR was increased by 11. 7%. Field well group test increased oil by 2 700 m3. Conclusions Wormlike micelle oil displacement technology can be used as an efficient oil displacement agent in offshore high water-cut reservoirs to effectively increase oil rate and reduce water production. Keywords: wormlike micelle; oil displacement; viscoelasticity; surfactant; interfacial tension [ABSTRACT FROM AUTHOR]

Copyright of Food & Machinery is the property of Food & Machinery Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Railway Science & Engineering is the property of Journal of Railway Science & Engineering Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)