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Effect of structural parameters on the setting performance of plug slips during hydraulic fracturing

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Petroleum Science 2022年第2期19卷 731-742页

作者： Chao Zheng Zeng-Kai Liu xin-lei Wu Aibaibu Abulimiti Jie Qin Xue-Fei Zheng Yong-Hong Liu Department of Chemical and Process Engineering University of SurreyGuildfordGU27XHUnited Kingdom College of Mechanical and Electronic Engineering China University of PetroleumQingdao266580China

Slip is one of the most critical components for the frac plug,which would lodge into the casing and lock the frac plug in place during the setting and anchoring ***,fracture failure of slip significantly affects the hydraulic fracturing effects and has attracted tremendous *** this paper,a three-dimensional contact model is applied to explore the setting process of *** effects of key structural parameters such as apex angle,inclination angle,and wedge angle on the contact characteristics of slip are systematically *** results indicate that the maximum contact stress appears at the contact area between slip tooth and the casing’s inner ***,the maximum contact stress generally increases with the increase of apex angle and inclination angle,while decrease linearly with the rise in the wedge *** results show that the slip teeth get blunt and appear severe plastic deformation,which arises from stress *** of biting area indicates that the experimental results are about 21.3%larger,which still have a reasonable agreement with the numerical *** obtained results can guide the parametric selection of plug slip and other similar components.

关键词： Hydraulic fracturing Plug slips Setting performance Fracture failure

Interference of harmonics emitted by different tunneling momentum channels in laser fields

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Chinese Physics B 2024年第9期33卷 366-372页

作者： Ling-Yu Zhang Zhuo-Xuan Xie Can Wang xin-lei Ge Jing Guo Institute of Atomic and Molecular Physics Jilin UniversityChangchun 130012China College of Physical Science and Technology Bohai UniversityJinzhou 121013China

By numerically solving the semiconductor Bloch equation(SBEs),we theoretically study the high-harmonic generation of ZnO crystals driven by one-color and two-color intense laser *** results show the enhancement of harmonics and the cut-off remains the same in the two-color field,which can be explained by the recollision trajectories and electron excitation from *** on the quantum path analysis,we investigate contribution of different ranges of the crystal momentum k of ZnO to the harmonic yield,and find that in two-color laser fields,the intensity of the harmonic yield of different ranges from the crystal momentum makes a big difference and the harmonic intensity is depressed from all k channels,which is related to the interferences between harmonics from symmetric k channels.

关键词： high-order harmonic generation the semiconductor Bloch equation k-resolvedinter-bandhar-monic spectrum four-step semiclassical model

Comparison of the fraction of olfactory receptor pseudogenes in wolf (Canis lupus) with domestic dog (Canis familiaris)

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Journal of Forestry Research 2011年第2期22卷 275-280页

作者： ZHANG Hong-hai WEI Qin-guo ZHANG Huan-xin CHEN lei College of Life Science Qufu Normal University Qufu 273165 Shandong Province China.

Olfactory receptors（ORs）,the first dedicated molecules with which odorants physically interact to arouse an olfactory sensation,constitute the largest gene family in *** and wolves,like many other mammals,have a highly developed capability to detect and identify odorant molecules,even at minimum *** this study,the olfactory receptor repertoire from domestic dog and its closest relative,the wolf,were sequenced to estimate the fraction of pseudogenes in each *** fraction of disrupted olfactory receptor genes in dog was 17.78%,whereas,that in wolf was 12.08%.As expected the dog was less dependent on olfaction than the wolf,and the dog had more olfactory receptor ***,the observed difference between the two subspecies was not at the significant level（χ2 = 1.388,p = 0.239 0.05）.The values indicated that although domestication might play a role in the reduction of OR genes,it could not be concluded that the living environment provided by domestication lead to a significant reduction of the functional olfactory receptor ***,the purpose of domestication may also have influence on the ratio of functional olfactory receptor genes reduction.

关键词： olfactory receptor wolf domestic dog pseudogene

Implementation of complete two—dimensional bandgap in photonic crystals of square Bravais lattice using complex unit cell

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Chinese Physics B 2003年第5期12卷 571-572页

作者： QiuGao-xin LinFang-lei LiYong-Ping DepartmentofPhysics UniversityofScienceandTechnologyofChinaHefei230026China

Controlling the Reactivity of IBA-N_(3)by Switching Halogen Salts:Providing a Universal Strategy for Haloazidation of Alkenes

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Chinese Journal of Chemistry 2024年第16期42卷 1839-1845页

作者： Chen-Xi Xia xin-lei Sun Jinfeng Zhang Yue Ren Yan Yu Kuai Wang Ling-Guo Meng Key Laboratory of Green and Precise Synthetic Chemistry and Applications Ministry of Education/School of Chemistry and Materials ScienceHuaibeiNormal UniversityHuaibeiAnhui 235000China

Although various routes have been reported for haloazidation,unavoidable problems exist,such as environmentally unfriendly monomer halogen,the need for in situ generation of unstable halogen azides(XN3),applicability to one type of haloazidation and inability to precisely control ***,we developed a universal strategy for haloazidation of alkenes through controlling the reactivity of IBA-N_(3) by switching halogen salts,allowing for the synthesis of a diversity of halogen azide *** studies have shown that by tuning the reactivity of IBA-N_(3) via switching halogen salts,different intermediates can be controllably produced to achieve regioselectivityand chemoselectivity in thehaloazidationof alkenes.

关键词： Haloazidation Alkene IBA-N_(3) Halogen salts Difunctionalization Selectivity Radicals Synthetic methods

Simulation and experimental research on extra-squeeze forming method during gradient sand molding

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China Foundry 2022年第4期19卷 288-298页

作者： Er-biao Jiang Zhong-de Shan Guang Cheng Shao-zong Wang Zhao-xian Gu xin-lei Wang State Key Laboratory of Advanced Forming Technology and Equipment China Academy of Machinery Science and Technology Group Co.Ltd.Beijing 100044China Nanjing University of Aeronautics and Astronautics Nanjing 210016China Beijing Union University Beijing 100101China

The flexible extrusion forming process (FEFP) is a sand mold patternless manufacturing technology that enables digital near-net shaping of complex sand molds. But, it is difficult to achieve the gradient sand molds with high surface strength and strong interior permeability by FEFP. To solve this problem, an extra-squeeze forming method based on FEFP for gradient sand mold was developed. To further reveal the extra-squeeze forming mechanism, based on the Johnson-Kendall-Roberts (JKR) theory and “gluing” notions, the single and double-sided squeeze models of gradient sand molds were established using the EDEM software. The squeezing processes of sand molds with different cavity depths of 60, 100, 140, 180, and 220 mm were systemically studied under single and double-sided squeeze conditions. The variation in the void fraction of sand mold as also investigated at a variety of extra-squeeze distances of 2, 3, 4, 5, and 6 mm, respectively. Simulation and test results show that a deeper cavity depth weakens the extrusion force transmission, which leads to a decrease in strength. The sand mold permeability and void fraction are identified to be positively correlated, while the tensile strength and void fraction appear to be negatively correlated. The void fraction of sand molds decreases with a longer extra-squeeze distance. A 6 mm extra-squeeze distance for the sand mold with 220 mm cavity depth results in a 26.8% increase in tensile strength with only a 5.7% reduction in the permeability. Hence, the extra- squeeze forming method can improve the quality of the sand mold by producing a gradient sand mold with high surface strength and strong interior permeability.

关键词： patternless casting gradient squeeze sand mold performance discrete element simulation void fraction

Endostatin inhibits hypertrophic scarring in a rabbit ear model

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2013年第3期14卷 224-230页

作者： Hai-tao REN Hang HU Yuan LI Hong-fei JIANG xin-lei HU Chun-mao HAN Department of Burns and Wound Center the Second Affiliated HospitalSchool of MedicineZhejiang University Department of Ultrasound Women's HospitalSchool of MedicineZhejiang University Assisted Reproduction Unit Department of Obstetrics and GynecologySir Run Run Shaw HospitalSchool of MedicineZhejiang University

Objective： The present study was designed to use an in vivo rabbit ear scar model to investigate the efficacy of systemic administration of endostatin in inhibiting scar formation. Methods： Eight male New Zealand white rabbits were randomly assigned to two groups. Scar model was established by making six full skin defect wounds in each ear. For the intervention group, intraperitoneal injection of endostatin was performed each day after the wound healed （about 15 d post wounding）. For the control group, equal volume of saline was injected. Thickness of scars in each group was measured by sliding caliper and the scar microcirculatory perfusion was assessed by laser Doppler flowmetry on Days 15, 21, 28, and 35 post wounding. Rabbits were euthanatized and their scars were harvested for histological and proteomic analyses on Day 35 post wounding. Results： Macroscopically, scars of the control group were thicker than those of the intervention group. Significant differences between the two groups were observed on Days 21 and 35 （p〈0.05）. Scar thickness, measured by scar elevation index （SEI） at Day 35 post wounding, was significantly reduced in the intervention group （1.09±0.19） compared with the controls （1.36±0.28）. Microvessel density （MVD） observed in the intervention group （1.73±0.94） was significantly lower than that of the control group （5.63±1.78） on Day 35. The distribution of collagen fibers in scars treated with endostatin was relatively regular, while collagen fibers in untreated controls were thicker and showed disordered alignment. Western blot analysis showed that the expressions of type I collagen and Bcl-2 were depressed by injection of endostatin. Conclusions： Our results from the rabbit ear hypertrophic scar model indicate that systemic application of endostatin could inhibit local hypertrophic scar formation, possibly through reducing scar vascularization and angiogenesis. Our results indicated that endostatin may promote the apoptosis of endothelial ce

关键词： Endostatin Hypertrophic scar Systemic administration

Cloud-Model-Based Feature Engineering to Analyze the Energy-Water Nexus of a Full-Scale Wastewater Treatment Plant

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Engineering 2024年第5期36卷 63-75页

作者： Shan-Shan Yang xin-lei Yu Chen-Hao Cui Jie Ding lei He Wei Dai Han-Jun Sun Shun-Wen Bai Yu Tao Ji-Wei Pang Nan-Qi Ren State Key Laboratory of Urban Water Resource and Environment Harbin Institute of TechnologyHarbin 150000China Key Laboratory of Environmental Biotechnology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China School of Civil and Environmental Engineering Harbin Institute of Technology(Shenzhen)Shenzhen 518055China China Energy Conservation and Environmental Protection Group Beijing 100089China

Wastewater treatment plants(WWTPs)are important and energy-intensive municipal *** energy consumption and relatively low operating performance are major challenges from the perspective of carbon ***,water-energy nexus analysis and models for WWTPs have rarely been reported to *** this study,a cloud-model-based energy consumption analysis(CMECA)of a WWTP was conducted to explore the relationship between influent and energy consumption by clustering its influent’s *** principal component analysis(PCA)and K-means clustering were applied to classify the influent condition using water quality and volume *** energy consumption of the WWTP is divided into five standard evaluation levels,and its cloud digital characteristics(CDCs)were extracted according to bilateral constraints and golden ratio *** results showed that the energy consumption distribution gradually dispersed and deviated from the Gaussian distribution with decreased water concentration and *** days with high energy efficiency were extracted via the clustering method from the influent category of excessive energy consumption,represented by a compact-type energy consumption distribution curve to identify the influent conditions that affect the steady distribution of energy *** local WWTP has high energy consumption with 0.3613 kW·h·m^(-3)despite low influent concentration and volumes,across four consumption levels from low(I)to relatively high(IV),showing an unsatisfactory operation and management *** average oxygenation capacity,internal reflux ratio,and external reflux ratio during high energy efficiency days recognized by further clustering were obtained(0.2924-0.3703 kg O_(2)·m^(-3),1.9576-2.4787,and 0.6603-0.8361,respectively),which could be used as a guide for the days with low energy ***,this study offers a water-energy nexus analysis method to identify influent conditions with operational manageme

关键词： Wastewater treatment plants Cloud-model theory Data mining Principal component analysis K-means clustering Cloud-model-based energy consumption analysis

High basal defense gene expression determines sorghum resistance to the whorl-feeding insect southwestern corn borer

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Insect Science 2013年第3期20卷 307-317页

作者： Wei-Ning Cheng Jia-xin lei William L. Rooney Tong-Xian Liu Keyan Zhu-Salzman Key Laboratory of Integrated Pest Management on Crops in Northwestern Loess Plateau Ministry of Agriculture Northwest A&F Uni- versity Yangling Shaanxi China Department of Entomology Department of Soil and Crop Sciences Vegetable & Fruit Improvement Center Texas A&M University College Station Texas United States

Southwestern corn borer （SWCB, Diatraea grandiosella） and fall armyworm （FAW, Spodopterafrugiperda） are major pests of sorghum in the southern United States. Host plant resistance is a desirable means for reducing plant damage and yield losses from both insects. In this study, we evaluated 12 sorghum lines for whorl-stage resistance to leaf-feeding SWCB and FAW in greenhouse and laboratory bioassays. Differential plant responses were detected against the two insects. Among 12 lines tested, CM1821, Della and PI196583 were resistant to both insects, while BTx2752 was largely susceptible. Line R.09110 was resistant to SWCB, but susceptible to FAW, whereas Redbine-60 was suscep- tible to SWCB, but not to FAW. In addition, we quantified various chemical components in the plants and determined their association with insect resistance. Tannin and chloro- phyll in leaves did not show any significant correlation with resistance to either insects, but contents of soluble protein in general were negatively correlated with resistance to both insects. Endogenous soluble sugar and dhurrin were only positively correlated with resistance to SWCB, but not with FAW resistance. To gain some molecular insight into resistance mechanism of sorghum to SWCB, we performed qPCR reactions for key genes encoding enzymes involved in dhurrin and jasmonic acid （JA） biosynthesis on selected resistant or susceptible lines. Although these genes were rapidly and strongly induced by insect feeding in all lines, the observed resistance is likely explained by higher constitutive dhurrin contents in some resistant lines and higher basal JA biosynthesis in others. Our results suggest that sorghum utilizes multiple strategies to defend itself against SWCB.

关键词： Diatraea grandiosella host plant resistance resistance mechanism sorghum,Spodoptera frugiperda