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The effect of betaine surfactants on the association behavior of associating polymer

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Petroleum Science 2021年第5期18卷 1441-1449页

作者： Ji-Jiang Ge Tian-Ci Zhang yi-Ping Pan xuan Zhang College of Petroleum Engineering China University of Petroleum(East China)Qingdao266580ShandongChina

The interfacial properties and rheological behavior of surfactant/polymer complex systems were measured to investigate the association behavior of the associating *** with the pure surfactant solution,there are two inflection points in the surface tension curve for the surfactant/polymer complex *** two inflection points are dependent on the surfactant type and polymer *** effect of surfactant on the rheological behavior of polymer can be divided into two ***,the addition of short-chain betaine surfactant is detrimental to the viscosity of polymer solution due to the electrostatic shielding ***,long-chain betaine surfactant also reduces the viscosity of polymer solutions at low ***,when the concentration of the long-chain betaine surfactant is relatively high,the long-chain betaine surfactant could form worm-like micelles that promote the intermolecular association and thus increase the number of associating junctions,thereby resulting in the augmentation of *** it is necessary to apply the long-chain betaine surfactant to build the polymer/surfactant flooding *** interaction model between surfactant and polymer is proposed,which is different from the traditional‘Three-Region Model’.

关键词： Betaine surfactant Associating polymer Surface tension Viscosity Intermolecular association

Influence of impulse waves generated by rocky landslides on the pressure exerted on bank slopes

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Journal of Mountain Science 2021年第5期18卷 1159-1176页

作者： CAO Ting WANG Ping-yi QIU Zhen-feng REN Jing-xuan Key Laboratory of Hydraulic and Waterway Engineering of Ministry of Education Chongqing Jiaotong UniversityChongqing 400074China Engineering Research Center of Diagnosis Technology and Instruments of Hydro-Construction Chongqing Jiaotong UniversityChongqing 400074China

Rocky landslides on river banks can result in the generation of ultra-high waves,which may destroy structures on the opposite *** methods to calculate the pressure on bank slopes under the effect of impulse waves generated by landslides are,however,few and of low ***,in this study,a three-dimensional physical model test was conducted by taking into account factors such as landslide geometry parameters and the bank slope *** model test section was generalized on the basis of a certain section of the Three Gorges reservoir area as a prototype,after which the wave parameters and wave pressure acting on the bank slope were ***,the magnitude,acting point,and distribution of the pressure of the impulse waves generated by the rocky landslide upon the bank slope were *** distribution curve of the impact pressure was similar to that calculated using theСНиПⅡ57-75 formula,and the experimental pulsating pressure value was close to the value calculated using the Subgrade *** on the test results,a power function of the relative pulsating pressure steepness with respect to the reciprocal of the wave steepness,relative water depth,and slope ratio was *** acting point of the maximum pulsating pressure was found to be located near the still water ***,an empirical formula for calculating the envelope of the maximum pulsating pressure distribution curve was *** formulas can serve as a theoretical basis for the prediction of impulse wave pressure generated owing to landslides on bank slopes.

关键词： Rocky landslide Impact pressure Pulsating pressure Wave pressure steepness Distribution curve

Automatically Identifying Calling-Prone Higher-Order Functions of Scala Programs to Assist Testers

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Journal of Computer Science & Technology 2020年第6期35卷 1278-1294页

作者： yi-Sen Xu Xiang-Yang Jia Fan Wu Lingbo Li Ji-Feng xuan School of Computer Science Wuhan UniversityWuhan 430072China Turing Intelligence Technology Limited LondonEC2Y 9STU.K.

For the rapid development of internetware, functional programming languages, such as Haskell and Scala, can be used to implement complex domain-specific applications. In functional programming languages, a higher-order function is a function that takes functions as parameters or returns a function. Using higher-order functions in programs can increase the generality and reduce the redundancy of source code. To test a higher-order function, a tester needs to check the requirements and write another function as the test input. However, due to the complex structure of higher-order functions, testing higher-order functions is a time-consuming and labor-intensive task. Testers have to spend an amount of manual effort in testing all higher-order functions. Such testing is infeasible if the time budget is limited, such as a period before a project release. In practice, not every higher-order function is actually called. We refer to higher-order functions that are about to be called as calling-prone ones. Calling-prone higher-order functions should be tested first. In this paper, we propose an automatic approach, namely PHOF, which predicts whether a higher-order function of Scala programs will be called in the future, i.e., identifying calling-prone higher-order functions. Our approach can assist testers to reduce the number of higher-order functions of Scala programs under test. In PHOF, we extracted 24 features from source code and logs to train a predictive model based on known higher-order function calls. We empirically evaluated our approach on 4832 higher-order functions from 27 real-world Scala projects. Experimental results show that PHOF based on the random forest algorithm and the Synthetic Minority Oversampling Technique Processing strategy (SMOTE) performs well in the prediction of calls of higher-order functions. Our work can be used to support the scheduling of limited test resources.

关键词： higher-order function testing tool test management Scala program internetware

Exact quantum dynamics for two-level systems with time-dependent driving

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Chinese Physics B 2024年第12期33卷 79-85页

作者： Zhi-cheng He yi-xuan Wu Zheng-Yuan Xue Key Laboratory of Atomic and Subatomic Structure and Quantum Control(Ministry of Education) Guangdong Basic Research Center of Excellence for Structure and Fundamental Interactions of Matterand School of PhysicsSouth China Normal UniversityGuangzhou 510006China Guangdong Provincial Key Laboratory of Quantum Engineering and Quantum Materials Guangdong-Hong Kong Joint Laboratory of Quantum Matterand Frontier Research Institute for PhysicsSouth China Normal UniversityGuangzhou 510006China Hefei National Laboratory Hefei 230088China

It is well known that the time-dependent Schrrödinger equation can only be solved exactly in very rare cases,even for two-level quantum ***,finding the exact quantum dynamics under a time-dependent Hamiltonian is not only fundamentally important in quantum physics but also facilitates active quantum manipulations for quantum information *** this work,we present a method for generating nearly infinite analytically assisted solutions to the Schrödinger equation for a qubit under time-dependent *** analytically assisted solutions feature free parameters with only boundary restrictions,making them applicable in a variety of precise quantum *** to the general form of the time-dependent Hamiltonian in our approach,it can be readily implemented in various experimental setups involving ***,our scheme offers new solutions to the Schrödinger equation,providing an alternative analytical framework for precise control over qubits.

关键词： quantum computation quantum control analytical solution

Dual strategy of modulating growth temperature and inserting ultrathin barrier to enhance the wave function overlap in type-Ⅱ superlattices

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Nano Research 2022年第6期15卷 5626-5632页

作者： Yuyang Wu Yahui Zhang yi Zhang Yunhao Zhao Yu Zhang yingqiang Xu Chongyun Liang Zhichuan Niu yi Shi Renchao che Laboratory of Advanced Materials Shanghai Key Lab of Molecular Catalysis and Innovative MaterialsDepartment of Materials ScienceFudan UniversityShanghai 200438China State Key Laboratory for Superlattices and Microstructures Institute of SemiconductorsChinese Academy of SciencesBeijing 100083China National Laboratory of Solid-State Microstructures School of Electronic Science and Engineering and CollaborativeInnovation Center of Advanced MicrostructuresNanjing UniversityNanjing 210093China Joint-Research Center for Computational Materials Zhejiang LaboratoryHangzhou 311100China

Maximizing wave function overlap(WFO)within type-II superlattices(T2SL)is demonstrated to be important for improving their photoelectric properties,such as optical transition strength and quantum efficiency,which,however,remains a great challenge for ***,the dual strategy of modulating growth temperature and inserting ultrathin AlAs barrier into the AlSb layers is presented to enhance the WFO in InAs/AlSb *** charge distributions and strain states indicate that moderate growth temperature of 470°C promotes the As-Sb exchange at AlSb-on-InAs(AOI)interfaces,which would introduce skew of energy band structure towards InAs-on-AlSb(IOA)*** band structure could drive electrons and holes to the IOA interfaces simultaneously,thus resulting in the enhanced *** this basis,insertion of relatively thick(0.3 nm)AlAs layers is found to squeeze more holes towards adjacent interfaces,boosting the WFO *** InAs/AlSb superlattices with optimized WFO reveal better optical performance,where the peak intensity shows 50%improvement in the PL spectra than the original ***,a dual-miniband radiative transition mechanism appears in the InAs/AlSb superlattice with relatively thick AlAs intercalation,which helps broaden the wavelength range of the superlattice.

关键词： wave function overlap type-II superlattices photoelectric properties charge distribution energy band alignment

Two novel antimicrobial peptides from skin venoms of spadefoot toad Megophrys minor

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Chinese Journal of Natural Medicines 2016年第4期14卷 294-298页

作者： YANG Hong-Ling SHEN Zhi-Qiang LIU xuan KONG yi School of Pharmaceutical Science and Yunnan Key Laboratory of Pharmacology for Natural Products Kunming Medical University School of Life Science & Technology China Pharmaceutical University

Amphibian skin contains rich bioactive peptides. Especially, a large amount of antimicrobial peptides have been identified from amphibian skin secretions. Antimicrobial peptides display potent cytolytic activities against a range of pathogenic bacteria and fungi and play important defense roles. No antimicrobial peptides have been reported from toads belonging to the family of Pelobatidae. In this work, two novel antimicrobial peptides(Megin 1 and Megin 2) were purified and characterized from the skin venoms of spadefoot toad Megophrys minor(Pelobatidae, Anura, Amphibia). Megin 1 had an amino acid sequence of FLKGCWTKWYSLKPKCPF-NH2, which was composed of 18 amino acid residues and contained an intra-molecular disulfide bridge and an amidated C-terminus. Megin 2 had an amino acid sequence of FFVLKFLLKWAGKVGLEHLACKFKNWC, which was composed of 27 amino acid residues and contained an intra-molecular disulfide bridge. Both Megin 1 and Megin 2 showed potential antimicrobial abilities against bacteria and fungi. The MICs of Megin 1 against Escherichia coli, Bacillus dysenteriae, Staphylococcus aureus, Bacillus subtilis, and Candida albicans were 25, 3, 6.25, 3, and 50 μg·m L^(-1), respectively. The corresponding MICs for Megin 2 were 6.25, 1.5, 12.5, 1.5, and 12.5 μg·m L^(-1), respectively. They also exerted strong hemolytic activity against human and rabbit red cells. The results suggested that megin peptides in the toad skin of M. minor displayed toxic effects on both eukaryotes and prokaryotes. This was the first report of antimicrobial peptides from amphibians belonging to the family of Pelobatidae.

关键词： Antimicrobial peptides Amphibian Pelobatidae Skin venoms

Reducing Dietary Cation-Anion Difference on Acid-Base Balance, Plasma Minerals Level and Anti-Oxidative Stress of Female Goats

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Journal of Integrative Agriculture 2013年第9期12卷 1620-1628页

作者： WU Wen-xuan YANG yi ZHANG Ji-kun LI Sheng-li College of Animal Science Guizhou University Institute of Animal Science Jiangxi Academy of Agricultural Sciences State Key Laboratory of Animal Nutrition Ministry of Science and Technology/College of Animal Science and TechnologyChina Agricultural University

Reducing dietary cation-anion difference （DCAD） has been proved an effective way to prevent milk fever in dairy cows. Based on the similar physiological gastro-intestinal tract anatomy and metabolic process between female goats and dairy cows, this study was conducted to evaluate the effects of varying DCAD on fluid acid-base status, plasma minerals concentration and anti-oxidative stress capacity of female goats. Urinary pH, plasma Ca, P and Mg; and anti-oxidative stress indices of total superoxide dismutase （T-SOD）, hydrogen peroxide （HzO2）, glutathione peroxidase （GSH-Px） and malondialdehyde （MDA） were determined to evaluate the effect. Forty-eight Guizhou black female goats （（15±1.9） mon of old, （22.3±3.75） kg of BW） were randomly allocated to 4 blocks of 12 goats each and were fed 1 of 4 diets differed in DCAD level （calculated as Na＋K-C1-S, mEq kg-1 DM）. Levels of DCAD were preliminarily designed to be control （＋ 150 mEq kg^-1 DM, CON）, high DCAD （＋300 mEq kg^-1 DM, HD）, low DCAD （0 mEq kg^-1 DM, LD） and negative DCAD （-150 mEq kg^-1 DM, ND）, respectively. A commercial anionic salts （Animate） and sodium bicarbonate （NaHCO3） were supplemented to reduce and increase DCAD level, respectively. There was no difference in dry matter intake for 4 groups of goats. Urine pH was aggressively decreased （P〈0.0001） with reduced DCAD and there was a strong association between DCAD and urine pH （R2=0.793, P〈0.0001）. Compared with CON and HD feeding of LD and ND resulted in greater （P〈0.05） plasma Ca concentration. Plasma P level was increased （P〈0.05） when anionic salts were supplemented. The DCAD alteration did not affected （P〉0.05） plasma Mg level. There was no significant （P〉0.05） difference in plasma GSH-Px activity and H202, but anionic salts supplementation in LD and ND significantly increased （P〈0.05） plasma T-SOD activity and tended to reduce MDA （P〈0.1） over HD and CON. Results from this study indicated that reducing DCAD could decrease urine pH and increase plasma

关键词： dietary cation-anion difference urine pH plasma calcium anti-oxidative stress female goats

Design and optimization of low-energy transfer orbit to Mars with multi-body environment

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Science China(Technological Sciences) 2015年第10期58卷 1660-1671页

作者： LU yi LI HengNian LI JiSheng che Zheng YANG yiKang YANG Yuan SUN Yang School of Electronic and Information Engineering Xi’an Jiaotong University State Key Laboratory of Astronautic Dynamics (ADL) Affiliated to Xi’an Satellite Control Center College of Aeronautics and Astronautics University of Electronic Science and Technology of China School of Aerospace Xi’an Jiaotong University

This paper discusses the problem of design and optimization of low-energy transfer orbit with multi-body environment. A new integrative method is proposed to effectively solve the problem, in which the parameterized patched manifolds in CR3BP(circular restricted three-body problems), the shape-based method with multi-body environment, the homotopic method with multi-body environment, and the low-thrust capturing and descending algorithm with multi-body environment are all included. Firstly, the parameters describing the patched manifolds in CR3 BP are optimized until the least total absolute velocity increment has been got, including the employment of the shape-based method with multi-body environment. Secondly, the low-thrust control laws of the transfer orbit are optimized employing the homotopic method with multi-body environment that transfers the fuel optimization problem to an easier energy optimization problem. Thirdly, the low-thrust descending orbit around Mars is computed using the laws proposed in this paper. As a typical example, the Earth-Mars transfer orbit design is discussed. The results showed that the parameters describing the patched manifolds could be optimized by the DE(differential evolution) algorithm effectively; the homotopic method with multi-body environment could get the optimal value that meets the first order optimality conditions; and the low-thrust descending orbit could effectively be captured by Mars and finally become a circular parking orbit around it by the hypothesis control laws proposed in this paper. It shows that the final fuel cost is much less than the optimal transfer in the patched two-body problems. In conclusion, the method proposed in this paper could effectively solve the low-energy low-thrust optimal control problem in multi-body environment for the future deep space explorations.

关键词： orbit optimization multi-body patched manifolds low-energy low-thrust

Effects of Silicon on the Microstructure and Mechanical Properties of 15–15Ti Stainless Steel

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Acta Metallurgica Sinica(English Letters) 2020年第11期33卷 1583-1590页

作者： Hao-Yu yi Tian Liang Min Wang Xiang-Dong Zha ying-che Ma Kui Liu China Nuclear Power Technology Research Institute Shenzhen 518000China Key Laboratory of Nuclear Materials and Safety Assessment Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China

Effects of silicon on the microstructure and mechanical properties of 20% cold-worked 15-15 Ti austenitic stainless steels are systemically investigated by uniaxial tensile tests,scanning and transmission electron microscope observations,and strength *** results reveal that a large number of deformation twins are formed in the 20% cold-worked steels with various silicon *** volume fraction of deformation twins and the density of dislocations increase with silicon content,while the twin thickness slightly decreases.A better strength-ductility combination is achieved by silicon addition,since the yield strength of the steel with 2% silicon is 61 MPa higher than that of the steel with 1% silicon,while their uniform elongations are almost both equal to 16%.The yield strength of the 15-15 Ti stainless steels is predominantly contributed by the solid solution,dislocation and deformation twin strengthening effects,which can be enhanced by silicon addition.

关键词： Austenitic stainless steel Silicon Microstructure Mechanical property