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Molecular simulation study of the stabilization process of NEPE propellant

Defence Technology（防务技术） 2023年第7期25卷 220-230页

作者： Ling-ze Kong ke-hai dong Ai-min Jiang Chuan-lu Yang Yan-hui Tang Yun-dong Xiao Department of Aircraft Engineering Naval Aviation UniversityYantai264001China School of Physics and Optoelectronic Engineering Ludong UniversityYantai264001China

In this reported study, the density functional theory(DFT) was used at the(U)B3LYP/6-311G(d,p) level to investigate the stabilization process of the nitrate ester plasticized polyether propellant(NEPE). Molecular simulations were conducted of the reaction that generates NO_(2), the autocatalytic and aging reaction triggered by the NO_(2), and the nitrogen dioxide absorption reaction of the stabilizers during the propellent stabilization process. These simulations were derived using the transition-state theory(TST)and variational transition-state theory(VTST). The simulation results suggested that the stabilization of the NEPE propellant consisted of three stages. First, heat and NO_(2) were generated during the denitrification reaction of nitroglycerine(NG) and 1,2,4-butanetriol trinitrate(BTTN) in the NEPE ***, nitroso products were generated by the reactions of N-Methyl-4-nitroaniline(MNA) and 2-nitrodiphenylamine(2NDPA) with NO_(2). Third, the stabilizers were exhausted and the autocatalytic reaction of NG and BTTN and the aging reaction of polyethylene glycol(PEG) were triggered by the heat and NO_(2)generated in the first stage. By comparing the energy barriers of the various reactions, it was found that the NO_(2)generated from the denitrification reaction significantly reduced the reaction energy barrier to 105.56-126.32 kJ/mol, also increased the reaction rate constant, and decreased the thermal stability and energetic properties of the NEPE propellant. In addition, the NO_(2)also weakened the mechanical properties of the NEPE propellant by attacking the-CH2groups and the O atoms in the PEG molecular chain. The energy barriers of the reactions of MNA and 2NDPA with NO_(2)(94.61-133.61 k J/mol) were lower than those of the autocatalytic and decomposition reactions of NG, BTTN, and the aging reactions of PEG(160.30-279.46 kJ/mol). This indicated that, by eliminating NO_(2), the stabilizer in the NEPE propellant can effectively prevent NO_(2)from

关键词： NEPE propellant Stabilizer Stabilization process Molecular simulation DFT VTST

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多业务异构网络的呼叫接纳控制

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中国科学技术大学学报 2018年第1期48卷 42-46页

作者：徐可黄海董广忠王传启中国科学技术大学信息科学技术学院安徽合肥230026

呼叫接纳控制作为异构网络系统资源管理的重要部分,直接影响整个网络资源使用的有效性,因此在异构网络环境下设计一个合理有效的接纳控制策略至关重要.考虑了异构网络中的呼叫接入问题,根据各类服务的带宽需求以及提供的利润差异,针对... 详细信息

呼叫接纳控制作为异构网络系统资源管理的重要部分,直接影响整个网络资源使用的有效性,因此在异构网络环境下设计一个合理有效的接纳控制策略至关重要.考虑了异构网络中的呼叫接入问题,根据各类服务的带宽需求以及提供的利润差异,针对其随机分布的特性,建立连续时间Markov分析模型,提出一种基于缓存的呼叫接入控制算法,并采取迭代策略对算法进行优化.仿真实验验证了算法的有效性,最终的控制策略是系统长期平均利润最大化的最优策略.

关键词：异构网络呼叫接纳控制连续时间Markov 策略优化

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风向对航母舰载机复飞路径上风湍流的影响

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科学技术与工程 2016年第34期16卷 121-126页

作者：袁书生董可海张旭东海军航空工程学院烟台264001

采用低速气流运动控制方程组和湍流大涡模拟方法,研究了风速大小不变、不同风向对航母舰载机复飞路径上风脉动的影响,得到了航母复飞跑道较低高度处压强和速度脉动随风向的变化关系。结果表明,风向对复飞跑道上空压强有着较大的影响,存... 详细信息

采用低速气流运动控制方程组和湍流大涡模拟方法,研究了风速大小不变、不同风向对航母舰载机复飞路径上风脉动的影响,得到了航母复飞跑道较低高度处压强和速度脉动随风向的变化关系。结果表明,风向对复飞跑道上空压强有着较大的影响,存在风向角较正向来风相比,压强时均值有所降低,但脉动幅度有所增加,相同风向角时,左舷来风较右舷压强时均值略低,脉动幅度却稍高。压强脉动幅度越高,则大尺度脉动的周期越小。风向对复飞跑道上空气流速度的影响主要是航向速度和横向速度时均值,对垂向速度的时均值影响不大;对速度脉动的影响趋势是一致的,侧向风时的速度脉动均比正向风时大;相同风向角时,左舷风时比右舷风时大。无论风向如何,复飞起点附近均出现了长时间的下洗速度;风向角越大,下洗速度越大;相同风向角下,左舷风时下洗速度较右舷风时大。

关键词：航空母舰大涡模拟风向影响风脉动复飞

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Small extracellular vesicles derived from human induced pluripotent stem cell-differentiated neural progenitor cells mitigate retinal ganglion cell degeneration in a mouse model of optic nerve injury

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Neural Regeneration Research 2025年第2期20卷 587-597页

作者： Tong Li Hui-Min Xing hai-dong Qian Qiao Gao Sheng-Lan Xu Hua Ma Zai-Long Chi State key Laboratory of Ophthalmology Optometry and Visual ScienceEye HospitalWenzhou Medical UniversityWenzhouZhejiang ProvinceChina National Clinical Research Center for Ocular Diseases Eye HospitalWenzhou Medical UniversityWenzhouZhejiang ProvinceChina

Several studies have found that transplantation of neural progenitor cells(NPCs)promotes the survival of injured ***,a poor integration rate and high risk of tumorigenicity after cell transplantation limits their clinical *** extracellular vesicles(sEVs)contain bioactive molecules for neuronal protection and *** studies have shown that stem/progenitor cell-derived sEVs can promote neuronal survival and recovery of neurological function in neurodegenerative eye diseases and other eye *** this study,we intravitreally transplanted sEVs derived from human induced pluripotent stem cells(hiPSCs)and hiPSCs-differentiated NPCs(hiPSC-NPC)in a mouse model of optic nerve *** results show that these intravitreally injected sEVs were ingested by retinal cells,especially those localized in the ganglion cell *** with hiPSC-NPC-derived sEVs mitigated optic nerve crush-induced retinal ganglion cell degeneration,and regulated the retinal microenvironment by inhibiting excessive activation of *** analysis further revealed that hiPSC-NPC derived sEVs transported neuroprotective and anti-inflammatory miRNA cargos to target cells,which had protective effects on RGCs after optic nerve *** findings suggest that sEVs derived from hiPSC-NPC are a promising cell-free therapeutic strategy for optic neuropathy.

关键词： exosome miRNA neural progenitor cell neurodegeneration neuroinflammation neuroprotection optic nerve crush optic neuropathy retinal ganglion cell small extracellular vesicles

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Negative efficacy of antidepressants in pharmacotherapy of child and adolescent depression

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World Journal of Psychiatry 2025年第1期15卷 32-36页

作者： Min Xu hai-Ying Jin Feng-Li Sun Wei-dong Jin Department of Psychiatry Zhejiang Chinese Medical UniversityHangzhou 310053Zhejiang ProvinceChina Department of Psychiatry Tongde Hospital of Zhejiang ProvinceHangzhou 310012Zhejiang ProvinceChina Department of Psychiatry Zhejiang Provincial Mental Health CenterHangzhou 311122Zhejiang ProvinceChina

Antidepressants are the main drugs used to treat depression,but they have not been shown to be effective in the treatment of child and adolescent ***,many adolescent depression treatment guidelines still recommend the use of antidepressants,especially specific serotonin re-uptake *** studies have suggested that antidepressants have little therapeutic effect but many side effects,such as switching to mania,suicide,and non-suicidal self injury(NSSI),in the treatment of child and adolescent *** the process of developing guidelines,drug recommendations should not only focus on impro-ving symptoms,but they should also consider potential side *** review discusses the serious side effects of antidepressants,including switching to mania,suicide,and NSSI.

关键词： Child depression Adolescent depression Antidepressant Switch Suicide Non-suicidal self injury

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CNKSR2 interactome analysis indicates its association with the centrosome/microtubule system

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Neural Regeneration Research 2025年第8期20卷 2420-2432页

作者： Lin Yin Yalan Xu Jie Mu Yu Leng Lei Ma Yu Zheng Ruizhi Li Yin Wang Peifeng Li hai Zhu dong Wang Jing Li Institute for Translational Medicine The Affiliated Hospital of Qingdao UniversityMedical CollegeQingdao UniversityQingdaoShandong ProvinceChina School of Basic Medicine Qingdao UniversityQingdaoShandong ProvinceChina College of Life Sciences and School of PharmacyMedical CollegeQingdao UniversityQingdaoShandong ProvinceChina Department of Urology Qingdao Municipal Hospital Affiliated to Qingdao UniversityQingdaoShandong ProvinceChina

The protein connector enhancer of kinase suppressor of Ras 2(CNKSR2),present in both the postsynaptic density and cytoplasm of neurons,is a scaffolding protein with several protein-binding *** of the CNKSR2 gene have been implicated in neurodevelopmental disorders,particularly intellectual disability,although the precise mechanism involved has not yet been fully *** has demonstrated that CNKSR2 plays a role in facilitating the localization of postsynaptic density protein complexes to the membrane,thereby influencing synaptic signaling and the morphogenesis of dendritic ***,the function of CNKSR2 in the cytoplasm remains to be *** this study,we used immunoprecipitation and high-resolution liquid chromatography-mass spectrometry to identify the interactors of *** a combination of bioinformatic analysis and cytological experiments,we found that the CNKSR2 interactors were significantly enriched in the proteome of the *** also showed that CNKSR2 interacted with the microtubule protein DYNC1H1 and with the centrosome marker *** colocalization analysis confirmed the centrosomal localization of *** we downregulated CNKSR2 expression in mouse neuroblastoma cells(Neuro 2A),we observed significant changes in the expression of numerous centrosomal *** manipulation also affected centrosome-related functions,including cell size and shape,cell proliferation,and ***,we found that CNKSR2 interactors were highly enriched in de novo variants associated with intellectual disability and autism spectrum *** findings establish a connection between CNKSR2 and the centrosome,and offer new insights into the underlying mechanisms of neurodevelopmental disorders.

关键词： autism spectrum disorder centrosome CNKSR2 intellectual disability interactome mass spectrometry microtubule neurodevelopmental disease protein complexes protein-protein interactions

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Stabilization of stochastic nonholonomic systems

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2006年第10期7卷 1742-1747页

作者： ke hai-sen YE Xu-dong Department of Electrical Engineering Zhejiang University Hangzhou 310027 China

In this work, we investigate the stabilization control design of nonholonomic stochastic system in strict-feedback form. Under the condition of all states being available for feedback, a state feedback controller was developed via the stochastic Lyapunov-like theorem and backstepping design technique. The controllers guarantee all states of the closed-loop system are bounded in probability, and largely asymptotically stable when the stochastic disturbances equal to zero at the equilibrium point of the open-loop system. Besides, the time-varying technique was introduced to avoid the uncontrollable state of chained system.

关键词： Time-varying technique Nonholonomic Backstepping Stochastic

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Antibacterial copper-bearing titanium alloy prepared by laser powder b e d fusion for superior mechanical performance

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Journal of Materials Science & Technology 2023年第1期132卷 100-109页

作者： Huan Liu hai Wang Ling Ren dong Qiu ke Yang School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China Shi-changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China Centre for Additive Manufacturing School of EngineeringRMIT UniversityMelbourneVictoriaAustralia Binzhou Institute of Technology Weiqiao-UCAS Science and Technology ParkBinzhouShandong Province256606China Shandong key Laboratory of Advanced Aluminium Materials and Technology Weiqiao-UCAS Science and Technology ParkBinzhouShandong Province256606China

Copper element was added in pure titanium to produce a new biomedical titanium-copper alloy by laser powder bed fusion(LPBF).Addition of copper can eliminate the mismatch of high strength but poor duc-tility problem caused by lathα’martensite,which is the usual microstructure of nearαtitanium alloy fabricated by *** of by the usual trade-offrelationship between strength and ductility,which is a long-standing challenge for martensitic titanium alloys,in this study,we proposed a boundary engineer-ing strategy and aim to synergistically enhance the strength and ductility of martensitic titanium alloy fabricated by *** is hypothesized that whilst both low-angle and high-angle grain boundaries are beneficial to the strength,high-angle grain boundary can simultaneously improve the ductility of *** test this strategy,a Ti-5Cu(wt.%)alloy is selected to compare against pure titanium and Ti-6Al-4V at the same laser processing ***,TEM and XRD analysis show that the as-fabricated LPBF Ti-5Cu alloy is comprised of partially tempered martensite with extraordinarily high number density of both high-angle and low-angle grain boundaries as well as low dislocation *** microstructure enables a high tensile strength of 940-1020 MPa,which is at a similar level as LPBF Ti-6Al-4V,and an excellent elongation of 13%-16%,twice as much as that of LPBF *** mechanism of microstruc-ture refinement in LPBF Ti-5Cu at different levels from prior-βgrains,martensitic packets,blocks to laths is also discussed.

关键词： Titanium alloy Laser powder bed fusion Boundary engineering Martensite Mechanical properties

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Analysis of the anti-T2DM components in dichloromethane fraction of Schisandra sphenanthera and its mechanism

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Traditional Medicine Research 2025年第1期10卷 27-43页

作者： Shi-Bo Feng hai-Hui Jiang Hui-Li Kang Yi Jiang Hua-Wei Zhang Xiao-Mei Song Yu-Ze Li Wen-Li Huang dong-dong Zhang Chong Deng School of Pharmacy Shaanxi University of Chinese MedicineXianyang 712046China School of Pharmacy and Shaanxi Qinling Application Development and Engineering Center of Chinese Herbal Medicine Shaanxi University of Chinese MedicineXianyang 712046China key Laboratory for Research and Development of“Qin Medicine”of Shaanxi Administration of Traditional Chinese Medicine Xianyang 712046China Shaanxi key Laboratory of Research and Application of“Taibai Qi Yao” Xianyang 712046China

Background:The type 2 diabetes mellitus(T2DM)pharmacodynamic study of various parts of Schisandra sphenanthera was conducted in the previous stage,and it was found that dichloromethane extracted part(SDP)had a significant hypoglycemic ***,the components of SDP were analyzed,and the specific mechanism of its anti-T2DM was ***:We used a high-fat,high-sugar diet in combination with streptozotocin to induce a T2DM rat model,and the model rats were divided into two groups according to body weight and blood ***,oral glucose tolerance test,fasting blood glucose,low density lipoprotein cholesterol,superoxide dismutase,insulin,glycated hemoglobin,total cholesterol,nonesterified free fatty acids,alanine aminotransferase,high-density lipoprotein cholesterol,aspartate aminotransferase,malondialdehyde,and glutathione peroxidase were measured,organ indices were calculated,and pathological sections of pancreas and liver were *** 16S rRNA V3–V4 region of intestinal flora was sequenced to explore the effect of SDP on biochemical indicators and intestinal *** on the above indicators,the anti-T2DM mechanism of SDP in Schisandra sphenanthera was ***:After six weeks of administration,the biochemical indices of diabetic rats were diminished compared to the control *** SDP could significantly increase the gut microbialα-diversity index,resulting in significant changes in the flora of T2DM rats,with increased richness and diversity,reduced harmful flora,and significantly back-regulated the levels of acetic acid,propionic acid,and butyric ***:SDP can improve the symptoms associated with elevated blood glucose,dyslipidemia,elevated fasting insulin levels,and damaged glucose tolerance in *** against T2DM may be through the control of intestinal flora to normalize and exert anti-diabetic effect;its main active components may be lignans and terpenoids.

关键词： Schisandra sphenanthera T2DM intestinal flora HPLC

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The evolution of microstructure and mechanical properties during high-speed direct-chill casting in different Al–Mg_2Si in situ composites

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International Journal of Minerals,Metallurgy and Materials 2018年第9期25卷 1080-1089页

作者： dong-tao Wang hai-tao Zhang Lei Li hai-lin Wu ke Qin Jian-zhong Cui key Laboratory of Electromagnetic Processing of Materials Ministry of Education Northeastern University

The effect of high-speed direct-chill(DC) casting on the microstructure and mechanical properties of Al–Mg_2Si in situ composites and AA6061 alloy was investigated. The microstructural evolution of the Al–Mg_2Si composites and AA6061 alloy was examined by optical microscopy, field-emission scanning electron microscopy(FE-SEM) and transmission electron microscopy(TEM). The results revealed that an increase of the casting speed substantially refined the primary Mg_2Si particles(from 28 to 12 μm), the spacing of eutectic Mg_2Si(from 3 to 0.5 μm), and the grains of AA6061 alloy(from 102 to 22 μm). The morphology of the eutectic Mg_2Si transformed from lamellar to rod-like and fibrous with increasing casting speed. The tensile tests showed that the yield strength, tensile strength, and elongation improved at higher casting speeds because of refinement of the Mg_2Si phase and the grains in the Al–Mg_2Si composites and the AA6061 alloy. High-speed DC casting is demonstrated to be an effective method to improve the mechanical properties of Al–Mg_2Si composites and AA6061 alloy billets.

关键词： Al–Mg2Si in situ composite casting speed grain size primary Mg2Si mechanical property

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