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A Novel Design of a Pre-separation Panel Structure to Protect Against the Impact of an Explosion in an Aircraft Plenum Chamber

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Acta Mechanica Solida Sinica 2024年第1期37卷 166-180页

作者： Zongxing liu xiang Yang Jun liu School of Aeronautics Northwestern Polytechnical UniversityXi'an 710072China COMAC Shanghai Aircraft Design and Research Institute Shanghai 201210China

To reduce the damage of the pressurizing panel structure of a fuselage caused by an explosion at the“least risk bomb location”in an aircraft structure,a new pre-separation panel structure was designed to resist blast ***,the dynamic strain response and morphology of impact damage of the new pre-separation panel were measured in an impact damage ***,the commercial software LS-DYNA was used to calculate the propagation of the blast shock wave,and the results were compared with empirical equations to verify the rationality of the numerical calculation ***,the fluid–structure coupling method was used to calculate the damage process of the pre-separation panel structure under the impact of an explosion wave and an impact *** calculated results were in good agreement with the test results,which showed the rationality of the calculation method and the *** residual strength of the damaged pre-separation panel was significantly higher than that of the original damaged *** results show that the new pre-separation panel structure is reasonable and has certain significance for guiding the design of plenum chambers with strong resistance to implosion for aircraft fuselages.

关键词： Pre-separation panel structure Explosive response Residual strength Aircraft plenum chamber Least risk bomb location

丹皮多糖-2b对肾上腺素模型小鼠降血糖作用研究

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生物学杂志 2003年第5期20卷 18-20页

作者：赵帜平何正祥刘祚军张部昌安徽大学生命科学学院合肥230039

目的　观察丹皮多糖-2b(PSM-2b)对肾上腺素模型小鼠血糖的影响。方法　采用300μg·kg-1肾上腺素腹腔注射复制小鼠高血糖模型。将小鼠随机分为三大组,各大组分别连续灌胃1周、2周或3周。每大组又分为六小组:对照组、模型组、阳性(降糖灵... 详细信息

目的　观察丹皮多糖-2b(PSM-2b)对肾上腺素模型小鼠血糖的影响。方法　采用300μg·kg-1肾上腺素腹腔注射复制小鼠高血糖模型。将小鼠随机分为三大组,各大组分别连续灌胃1周、2周或3周。每大组又分为六小组:对照组、模型组、阳性(降糖灵)组、PSM-2b大剂量(90mg·kg-1)组、中剂量(60mg·kg-1)组、小剂量(30mg·kg-1)组。按葡萄糖氧化酶法测血糖,按苯酚-硫酸法测肝糖元含量。结果　PSM-2b能够显著降低肾上腺素模型小鼠的高血糖,且其降血糖作用呈一定的量效关系。PSM-2b还能够促进血糖转化为糖元,显著提高模型小鼠肝糖元的含量。结论　PSM-2b可以通过抑制肾上腺素升血糖作用而降低血糖。

关键词： PSM—2b 肾上腺素模型小鼠降血糖肝糖元丹皮糖尿病

Numerical and theoretical investigations of heat transfer characteristics in helium-xenon cooled microreactor core

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Nuclear Science and Techniques 2023年第11期34卷 1-19页

作者： Tian‑Shi Wang xiang Chai Chao‑Ran Guan Xin‑Yue liu Jiao‑Long Deng Hui he Xiao‑Jing liu School of Nuclear Science and Engineering Shanghai JiaoTong UniversityShanghai 200240China

helium-xenon cooled microreactors are a vital technological solution for portable nuclear reactor power *** exam-ine the convective heat transfer behavior of helium-xenon gas mixtures in a core environment,numerical simulations are conducted on a cylindrical coolant channel and its surrounding solid *** numerical methods are used to determine the effect and mechanisms of power and its distribution,inlet temperature and velocity,and outlet pressure on the distribution and change trend of the axial Nusselt ***,a theoretical framework that can describe the effect of power variation on the evolution of the thermal boundary layer is employed to formulate an axial distribution cor-relation for the Nusselt number of the coolant channel,under the assumption of a cosine distribution for the axial *** on the simulation results,the correlation coefficients are determined,and a semi-empirical relationship is identified under the corresponding operating *** correlation derived in this study is consistent with the simulations,with an average relative error of 5.3%under the operating ***,to improve the accuracy of the predictions near the entrance,a segmented correlation is developed by combining the Kays correlation with the aforementioned *** new correlation reduces the average relative error to 2.9%and maintains satisfactory accuracy throughout the entire axial range of the channel,thereby demonstrating its applicability to turbulent heat transfer calculations for helium-xenon gas mixtures within the core *** findings provide valuable insights into the convective heat transfer behavior of a helium-xenon gas mixture in a core environment.

关键词： helium-xenon gas mixture Convective heat transfer Power distribution Numerical simulation Nusselt number correlation

Risk factors for flat anterior chamber after glaucoma filtration surgery

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International Journal of Ophthalmology(English edition) 2018年第8期11卷 1322-1329页

作者： xiang-Ji Zi Richard Filek xiang-Ge he Wei Wang Hong liu Lian he Yu-Rong Tang Lin Xie Department of Ophthalmology the Third Affiliated HospitalChongqing Medical University Chongqing 400016 China Department of Ophthalmology Institute of Surgery ResearchDaping Hospital Third Military Medical UniversityChongqing 400042 China Department of Pathology and Laboratory Medicine Western University London ON N6A 3K7 Canada Ivey Eye Institute St. Joseph's Hospital London ON N6A4V2 Canada Chongqing Aier Eye Hospital of Aier Eye Hospital Group Chongqing 400020 China Department of Ophthalmology People's Hospital Zhongshan Branch Chongqing 400013 China

AIM： To investigate the incidence rate and risk factors for grade Ⅲ flat anterior chamber（FAC） after glaucoma filtration surgery based on 5-year ***： Patients who underwent glaucoma filtration surgery in Daping hospital from January 2009 to December 2013 were enrolled in this retrospective study. The incidence of grade Ⅲ FAC following glaucoma filtration surgery was determined. Regression analysis was performed to investigate the influence of glaucoma type, surgical approach, age, and preoperative intraocular pressure（IOP） on the risk of postoperative ***： A total of 2179 eyes receiving anti-glaucoma surgery were included. Ninety-one eyes suffered from postoperative FAC, with an overall incidence rate of 4.18%. Of 471 eyes with primary open angle glaucoma（POAG）, grade Ⅲ FAC occurred in only 3 eyes（0.64%）. Primary angleclosure glaucoma（PACG） was diagnosed in 1076 eyes, 39（3.62%） of which developed grade Ⅲ FAC, including 12 eyes（12/300, 4%） with acute PACG（aP ACG） and 27 eyes（27/776, 3.48%） with chronic PACG（c PACG）. Six of 259 eyes（2.32%） with secondary glaucoma, 28 of 186 eyes（15.05%） with neovasular glaucoma, 1 of 66 eyes（1.52%） with congenital glaucoma, and 14 of 115 eyes（12.17%） with remnant glaucoma suffered from grade Ⅲ FAC. Of 6 eyes with mixed glaucoma, none developed grade Ⅲ FAC after surgery. When stratified by surgical approach, 24 of 766 eyes（3.13%） undergoing trabeculectomy, 21 of 924 eyes（2.27%） treated by trabeculectomy plus mitomycin C（MMC）, 18 of 109 eyes（16.51%） undergoing Ahmed glaucoma valve implantation, 23 of 201 eyes（11.44%） managed by Ahmed implantation plus MMC, and 5 of 133 eyes（3.76%） treated by Ahmed implantation plus lens extraction or vitrectomy developed grade Ⅲ FAC. Logistic regression analysis revealed that factors including neovasular glaucoma, remnant glaucoma, glaucoma valve implantation, glaucoma valve implantation＋MMC, glaucoma valve implantation＋vitrectomy, age〉60 y, and IOP at admission 〉50 mm Hg were significa

关键词： glaucoma filtration surgery grade IIIflat anterior chamber trabeculectomy glaucoma valveimplantation mitomycin C

Residual stress in the cylindrical drawing cup of SUS304 stainless steel evaluated by split-ring test

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Acta Mechanica Sinica 2016年第1期32卷 125-134页

作者： Liang-Hong Xiao Dao-he Yuan Jun-Zhong xiang Jin-Gang liu Yi-Chun Zhou School of Mechanical Engineering Xiangtan University Key Laboratory of Low Dimensional Materials & Application Technology Xiangtan University Ministry of Education

The residual stresses in the wall of a SUS304 stainless steel cylindrical drawing cup were evaluated by split-ring tests, and the influences of stamping die parame- ters on the residual stress were investigated. A new theoretical model of a split-ring test was developed to evaluate the resid- ual stress in a ring, which was verified to be reasonable and reliable by numerical simulations with ABAQUS code and by nanoindentation tests. Seven groups of split-ring tests were completed, and the residual stresses were calculated according to the theoretical model. The split-ring test results showed that the circumferential residual stress in the wall of the SUS304 stainless steel cylindrical drawing cup was very large and did not change with the different die comer radius. The circumferential residual stress first increased with the increase of drawing punch-die clearance, then was almost unchanged when the clearance increased greater than blank thickness 1 mm. Thus, a smaller clearance was suggested to be chosen to reduce the residual stress in the wall of the SUS304 stainless steel drawing cup.

关键词： Residual stress Split-ring test FEM numericalsimulation SUS304 stainless steel Nanoindentation

Proportional directional valve based automatic steering system for tractors

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Frontiers of Information Technology & Electronic Engineering 2016年第5期17卷 458-464页

作者： Jin-yi liu Jing-quan TAN En-rong MAO Zheng-he SONG Zhong-xiang ZHU Beijing Key Laboratory of Optimized Design for Modern Agricultural Equipment China Agricultural University

Most automatic steering systems for large tractors are designed with hydraulic systems that run on either constant flow or constant pressure. Such designs are limited in adaptability and applicability. Moreover, their control valves can unload in the neutral position and eventually lead to serious hydraulic leakage over long operation periods. In response to the problems noted above, a multifunctional automatic hydraulic steering circuit is presented. The system design is composed of a 5-way-3-position proportional directional valve, two pilot-controlled check valves, a pressure-compensated directional valve, a pressurecompensated flow regulator valve, a load shuttle valve, and a check valve, among other components. It is adaptable to most open-center systems with constant flow supply and closed-center systems with load feedback. The design maintains the lowest pressure under load feedback and stays at the neutral position during unloading, thus meeting the requirements for steering. The steering controller is based on proportional-integral-derivative(PID) running on a 51-microcontroller-unit master control chip. An experimental platform is developed to establish the basic characteristics of the system subject to stepwise inputs and sinusoidal tracking. Test results show that the system design demonstrates excellent control accuracy, fast response, and negligible leak during long operation periods.

关键词： Automatic steering system Hydraulic circuit Proportional directional valve Proportional-integral-derivative(PID) control

Characteristics and Mechanism of Reduction and Smelting-separation Process of Copper Slag

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Journal of Iron and Steel Research International 2015年第2期22卷 121-127页

作者： Jun ZHANG Yuan-hong QI Ding-liu YAN xiang-li CheNG Peng he State Key Laboratory of Advanced Steel Processes and Products China Iron and Steel Research Institute Group

The characteristics And mechanism of the reduction and smelting-separation process of the copper slag were studied by investigating the variation ：rule of metallization ratio, yield as well as carbon content of iron nuggets. The formation of molten slag is necessary for slag-iron separation, And iron is in half-molten state during smelting-separa- tion process, the carbon content of which is about 1.25 %. Carburization occurs through direct contact between car- bon and iron in essence, no matter in solid or molten state. The carburization rate is slow below 1 200 ℃ , which is inhibited by the existence of slag. Residual FeO in molten slag tends to form fayalite with SiOz in the copper slag, which is the root cause for the low mehing temperature of copper slag. The addition of CaO improves the reducibility of the copper slag, but Al2 O3 addition has no obvious effect. The melting temperature of slag affects the carburiza- tion extent in solid state, while the content of FeO in molten slag affects that in molten state, both of which co-de termine the carbon content in iron nuggets.

关键词： copper slag reduction smelting-separation earburization iron nugget

pH-controlled DNAzymes： Rational design and their applications in DNA-machinery devices

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Nano Research 2016年第10期9卷 3084-3092页

作者： Yuqi Chen Yanyan Song Zhiyong he Zijing Wang Wenting liu FuanWang Xiaolian Zhang xiang Zhou College of Chemistry and Molecular Sciences The Institute for Advanced Studies Wuhan University Wuhan 430072 China School of Medicine Wuhan University Wuhan 430071 China

The availability and reliability of strategies for molecular biosensing over a finely adjustable dynamic range is essential to enhance the understanding and control of vital biological process. To expand the versatility and utility of nucleic acid- related enzymes, we demonstrated a rational approach to acquiring tunable, pH-dependent deoxyribozymes （DNAzymes） with catalytic activities and response sensitivities that can be tuned through a simple change in solution pH. To do this, we capitalized upon the pH dependence of Hoogsteen interactions and designed i-motif- and triplex-based DNAzymes that can be finely regulated with high precision over a physiologically relevant pH interval. The modified DNAzymes are dependent upon pH for efficient cleavage of substrates, and their catalytic performance can be tuned by regulating the sequence of inserted i-motif/triplex structures. The principle of tunable, pH-dependent DNAzymes provides the opportunity to engineer pH-controlled DNA-machinery devices with unprecedented sensitivity to pH changes. For example, we constructed a DNA-walker device, the stepping rate of which could be adjusted by simply modulating solution pH within an interval of 5.6 to 7.4, as well as a DNA tetrahedron that can be opened at pH 6.4 and kept closed at pH 7.4. The potential of this approach is not limited to serve as pH-dependent devices, but rather may be combined with other elements to expand their practical usefulness.

关键词： pH iMNAzyme TNAzyme DNA walker DNA tetrahedron

2D hetero-structures based on transition metal dichalcogenides:fabrication,properties and applications

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Science Bulletin 2017年第16期62卷 1148-1161页

作者： Ping liu Bin xiang Department of Materials Science&Engineering CAS Key Lab of Materials for Energy Conversionand Synergetic Innovation Center of Quantum Information&Quantum PhysicsUniversity of Science and Technology of ChinaHefei 230026China

Recently,two dimensional transition metal dichalcogenides MX_2(M = Mo,W,etc; X = S,Se,Te) have ignited immense interests because of their unique structural and physical properties for the potential applications in the nano-optoelectronics,valley-spintronics etc. In terms of the structural compatibility and van der Waals interaction,two dimensional(2D) MX_2 layers can be fabricated into various lateral and vertical hetero-structures. The atomically-thin hetero-structures comprising different layered MX_2 provide a new platform for exploring fundamental physics and device technologies with unprecedented phenomenon and extraordinary functionalities. In this review,we report the recent progress about the fabrication,properties and applications of 2D hetero-structures based on transition metal dichalcogenides.

关键词： Transition metal dichalcogenides hetero-structures Chemical vapor deposition Charge transfer Optoelectronic devices