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Euler-Lagrange方程在船艇直线追及过程节能航行中的应用
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作者 黄奕飞 《科学技术创新》 2026年第3期9-12,共4页
为了解决船艇追及过程的节能航行问题,本文基于船艇对水上某恒定速度的移动目标的直线追及过程,采用变分法,根据船艇在追及过程遵守的牛顿第二定律、能量守恒定律以及所受水阻力与航速的关系式,推导出拉格朗日量,从而建立Euler-Lagrang... 为了解决船艇追及过程的节能航行问题,本文基于船艇对水上某恒定速度的移动目标的直线追及过程,采用变分法,根据船艇在追及过程遵守的牛顿第二定律、能量守恒定律以及所受水阻力与航速的关系式,推导出拉格朗日量,从而建立Euler-Lagrange方程。然后,通过求解Euler-Lagrange方程以给出船艇追及过程节能航行最优解。最优解所给出的结果表明,当船艇在水上以所追移动目标的3/2的航速匀速航行时,船艇在整追及过程的能耗最少。该理论模型突破传统经济航速理论中的局限,为船艇在追及过程节能航行操控提供理论支持与指导。 展开更多
关键词 euler-lagrange方程 变分法 经济航速 节能 追及
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Backstepping-based distributed coordinated tracking formultiple uncertain Euler-Lagrange systems 被引量:4
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作者 yanchao sun wenjia wang +2 位作者 guangfu ma zhuo li chuanjiang li 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2016年第5期1083-1095,共13页
Based on the idea of backstepping design, distributedcoordinated tracking problems under directed topology are discussedfor multiple Euler-Lagrange (EL) systems. The dynamicleader case is considered. First, with the... Based on the idea of backstepping design, distributedcoordinated tracking problems under directed topology are discussedfor multiple Euler-Lagrange (EL) systems. The dynamicleader case is considered. First, with the parameter-linearity property,a distributed coordinated adaptive control scheme is proposedfor EL systems in the presence of parametric uncertainties.Then, subject to nonlinear uncertainties and external disturbances,an improved adaptive control algorithm is developed by usingneural-network (NN) approximation of nonlinear functions. Bothproposed algorithms can make tracking errors for each followerultimately bounded. The closed-loop systems are investigated byusing the combination of graph theory, Lyapunov theory, and BarbalatLemma. Numerical examples and comparisons with othermethods are provided to show the effectiveness of the proposedcontrol strategies. 展开更多
关键词 multi-agent systems euler-lagrange (EL) system coordinatedtracking backstepping control distributed control.
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Synthesis and microencapsulation of oleic acid sterol ester liquid crystals for its application in sunscreen formulations
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作者 Xuze Liu Chang Xu +1 位作者 Liangliang Lin Hujun Xu 《日用化学工业(中英文)》 北大核心 2025年第11期1408-1418,共11页
This study reports the synthesis of oleic acid sterol ester with liquid crystalline properties and its enhanced stability and UV-blocking performance through microencapsulation.Oleic acid sterol ester was synthesized ... This study reports the synthesis of oleic acid sterol ester with liquid crystalline properties and its enhanced stability and UV-blocking performance through microencapsulation.Oleic acid sterol ester was synthesized via the esterification of phytosterol and oleic acid,whose structure was characterized using Fourier-transform infrared spectroscopy(FTIR)and mass spectrometry(MS).Its liquid crystalline behavior was confirmed via the polarized optical microscopy(POM),thermogravimetric analysis(TGA),differential scanning calorimetry(DSC),wide-angle X-ray scattering(WAXS),and small-angle X-ray scattering(SAXS).UV absorption tests were conducted to assess the UV-blocking performance of the oleic acid sterol ester liquid crystals.To improve the stability of its liquid crystalline structure,the oleic acid sterol ester was encapsulated into microcapsules through the emulsion polymerization.SPF measurements were performed on the sunscreen formulations containing liquid crystal microcapsules.The oleic acid sterol ester displayed cholesteric liquid crystalline behavior and strong UVA absorption,which indicates its suitability as a natural UV absorber.Microencapsulation further enhanced its stability and UV-blocking properties.SPF testing showed that the formulations with microcapsules achieved an SPF value of 7.01,which surpasses the nano titanium dioxide(SPF=6.23)and significantly outperform the unencapsulated liquid crystal formulations(SPF=2.65).This study highlights the potential of microencapsulated oleic acid sterol ester as a novel UV absorber in the sunscreen formulations,offers the enhanced stability and effective UV protection,and showcases its application potential in the innovative cosmetic products. 展开更多
关键词 PHYTOSTEROL liquid crystals MICROENCAPSULATION UV absorption sunscreen formulations SPF testing
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Sensory Characterizations and Optimization of Cashew Apple Jam Formulations Using Baobab Powder as a Source of Pectin
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作者 Marie Bianoun Louise Dégni Doudjo Soro +3 位作者 Essan Bla Zita N’Goran-Aw Djedjro Clément Akmel Nogbou Emmanuel Assidjo Kouassi Benjamin Yao 《Food and Nutrition Sciences》 2025年第1期120-136,共17页
Cashew processing in Côte d’Ivoire focuses only on the cashew nut, to the detriment of the apple. Only a very small proportion of the apple is processed into juice. The aim of this work is to enhance the value o... Cashew processing in Côte d’Ivoire focuses only on the cashew nut, to the detriment of the apple. Only a very small proportion of the apple is processed into juice. The aim of this work is to enhance the value of cashew apples by transforming them into jam. Specifically, the aim was first to characterize the sensory properties of cashew apple jam formulations using baobab powder as a source of pectin and then to optimise the formulations. A Box-Behken design with pH, Sugar, and Baobab as factors was used to model and characterize the jam sensory descriptors, and a multivariate analysis with SensomineR was used to characterize the jam formulations. The desirability function was used to optimise the formulations. The results show globally significant regressions at the 0.05 threshold for the sensory descriptors Gelling, Brilliance, Smell, Sweetness, and (-)Astringency, with the exception of (-)Salinity. The R2 coefficients are greater than 80%. The factors studied could have effects on the sensory descriptors of cashew jam formulations. The Baobab had the main effect on the gelling, smell, and astringency of the jams. Brilliance depended on the added sugar. A product effect (p < 0.001) was observed for the descriptors Smell, Gelling, Brilliance, and Sweetness, as these allowed the panelists to find differences between the formulations. Optimum jam formulation can be achieved with 51.56% sugar and 2.12% Baobab at a pH of 3.15. Cashew apple jam using Baobab offers opportunities to add value to apples that have long been abandoned in the field. It would be important to find conditions for prolonged storage of this jam. 展开更多
关键词 Cashew Apple Sensory Characterization Jam formulation Area Design Product Effect Overall Desirability
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Microencapsulation materials, processes, and their applications in drug formulations
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作者 Xiaorui Zhou 《Journal of Food Science, Nutrition and Health》 2025年第1期42-48,共7页
Microencapsulation technology is an emerging encapsulation method with significant applications in various fields,including pharmaceuticals and food products.This article reviews the preparation materials,principles o... Microencapsulation technology is an emerging encapsulation method with significant applications in various fields,including pharmaceuticals and food products.This article reviews the preparation materials,principles of preparation processes,and the advantages and disadvantages of microencapsulation.It also analyzes the application of microencapsulation technology in improving drug stability and in pharmaceutical formulations,providing a theoretical basis for selecting microencapsulation processes and offering references for research and development in drug formulation using microencapsulation technology. 展开更多
关键词 MICROENCAPSULATION preparation materials processing technology pharmaceutical formulations
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Study and Formulation of a Dietary Cold Sauce Based on Pumpkin Seed Oil and Quail Eggs
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作者 Koumba Hawa Toundoufedouno Kéloua Kourouma Adama Moussa Sakho 《Journal of Environmental Science and Engineering(B)》 2025年第1期36-45,共10页
This work focuses on the formulation of a dietary cold sauce,mayonnaise,which combines the therapeutic properties of two basic ingredients:PSO(Pumpkin Seed Oil)and quail egg,both of which are renowned for their high f... This work focuses on the formulation of a dietary cold sauce,mayonnaise,which combines the therapeutic properties of two basic ingredients:PSO(Pumpkin Seed Oil)and quail egg,both of which are renowned for their high functional properties.PSO is essentially made up of unsaturated fatty acids(50%to 65%)including linoleic acid,from the omega 6 family,oleic acid(20%to 50%),a monounsaturated fatty acid(omega 9),cucurbitin,phytosterols,tri-terpenes and vitamin E(3.5 mg%).The nutritional,fatty acid,vitamin and mineral compositions of the mayonnaise compared with the ingredients,the physico-chemical characteristics of the quail egg,the PSO and the tasting of the mayonnaise were determined and gave results in terms of variable contents which are recorded in Tables 2-8.The results obtained were satisfactory.Mayonnaise,a semi-solid emulsion of oil in water with viscoelastic properties due to the network formed by lipoproteins adsorbed around neighbouring drops of oil,was prepared using the ratio of quail egg and PSO 1/4.This study may offer an alternative way of making dietary sauces. 展开更多
关键词 Nutritional study food formulation dietary sauce PSO quail eggs
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Identification of bioactive compounds and molecular targets of Fuke Huahuang formulation to treat vaginitis
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作者 Huiyu Liu Jie Mo +3 位作者 Cheng Liang Qingting Chen Bin Yang Jiaqi Liu 《Animal Models and Experimental Medicine》 2025年第6期1095-1104,共10页
Background:Fuke Huahuang formulation(FHF)is widely used in the treatment of vaginitis,with clinical evidence indicating its promising anti-inflammatory properties.Methods:We explored the bioactive components and poten... Background:Fuke Huahuang formulation(FHF)is widely used in the treatment of vaginitis,with clinical evidence indicating its promising anti-inflammatory properties.Methods:We explored the bioactive components and potential mechanisms of FHF for treating vaginitis,and reveal its pharmacological activities against vaginitis.Results:A total of 12 anti-inflammatory components in FHF and 584 pharmacological targets were identified.Furthermore,1427 vaginitis-associated targets were identified,and 184 intersection targets between FHF and vaginitis were constructed for network analysis.Gene Ontology and pathway analysis revealed that the therapeutical targets of FHF against vaginitis are involved in modulating inflammatory stress,enhancing immunoregulation,reconstructing the microenvironment,and suppressing cell damage.Molecular docking analysis further suggested the possible direct binding of the bioactive compounds of FHF(fumarine)to the core targets,including AKT Serine/Threonine Kinase 1(AKT1),Signal Transducer and Activator of Transcription 3(STAT3),and nuclear factor-kappaB(NF-κB).Experimental validation found that FHF-treated vaginitis rats exhibited reduced intracellular AKT1,STAT3,and NF-κB protein expressions.Conclusion:Overall,we identified the bioactive compounds and pharmacological mechanisms of FHF against vaginitis,thus offering a theoretical fundament for exploring FHF for treating vaginitis in the future. 展开更多
关键词 biological validation biotargets Fuke Huahuang formulation MECHANISM VAGINITIS
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Fixed-time distributed average consensus tracking for multiple Euler-Lagrange systems
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作者 SUN Guhao ZENG Qingshuang CAI Zhongze 《Journal of Systems Engineering and Electronics》 2025年第2期523-536,共14页
This paper investigates the sliding-mode-based fixed-time distributed average tracking (DAT) problem for multiple Euler-Lagrange systems in the presence of external distur-bances. The primary objective is to devise co... This paper investigates the sliding-mode-based fixed-time distributed average tracking (DAT) problem for multiple Euler-Lagrange systems in the presence of external distur-bances. The primary objective is to devise controllers for each agent, enabling them to precisely track the average of multiple time-varying reference signals. By averaging these signals, we can mitigate the influence of errors and uncertainties arising dur-ing measurements, thereby enhancing the robustness and stabi-lity of the system. A distributed fixed-time average estimator is proposed to estimate the average value of global reference sig-nals utilizing local information and communication with neigh-bors. Subsequently, a fixed-time sliding mode controller is intro-duced incorporating a state-dependent sliding mode function coupled with a variable exponent coefficient to achieve dis-tributed average tracking of reference signals, and rigorous ana-lytical methods are employed to substantiate the fixed-time sta-bility. Finally, numerical simulation results are provided to vali-date the effectiveness of the proposed methodology, offering insights into its practical application and robust performance. 展开更多
关键词 distributed average tracking(DAT) fixed-time con-vergence euler-lagrange systems sliding mode control
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Inhalable formulations in pharmacy:from basic research to clinical applications
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作者 Yuying Yan Xuebin Yang Zhaoshuai Ji 《Journal of Chinese Pharmaceutical Sciences》 2025年第6期503-518,共16页
In recent years,the rising prevalence of respiratory diseases,coupled with advancements in biotechnology and pharmacology,has positioned inhalable formulations as a preferred method of drug administration.This approac... In recent years,the rising prevalence of respiratory diseases,coupled with advancements in biotechnology and pharmacology,has positioned inhalable formulations as a preferred method of drug administration.This approach enables direct and rapid delivery of medication to the lungs,maximizing therapeutic effects while minimizing dosage and potential side effects.In this review,we meticulously examined current literature and clinical trial databases to present a comprehensive overview of three key areas:(1)inhalation devices currently utilized in clinical settings;(2)the clinical applications of approved inhalable formulations;and(3)preclinical research on inhalable treatments targeting various lung conditions,including pulmonary infections,tuberculosis,lung cancer,pulmonary fibrosis,as well as systemic diseases like Parkinson’s disease.The objective was to delve into both foundational research and the clinical use of inhalable formulations within the pharmaceutical field,with the aim of fostering their broader adoption and guiding the development of inhalable therapies for a more comprehensive range of diseases. 展开更多
关键词 Inhalable formulations Inhalation device Inhaled vaccine Pulmonary infection Inhalable nanomedicine
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Shenzhuo formulation ameliorates diabetic nephropathy by regulating cytochrome P450-mediated arachidonic acid metabolism
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作者 Zhong-Yong Zhang Yu-Ming Wang +8 位作者 Ning Wang Yuan-Song Wang Hui Zhang Duo Wang Li-Xin Wang Huan-Tian Cui Wei-Bo Wen Shu-Quan Lv Yong-Jun Cao 《World Journal of Diabetes》 2025年第5期331-345,共15页
BACKGROUND Diabetic nephropathy(DN)is a major complication of diabetes,marked by progressive renal damage and an inflammatory response.Although research has investigated the pathological mechanisms underlying DN,effec... BACKGROUND Diabetic nephropathy(DN)is a major complication of diabetes,marked by progressive renal damage and an inflammatory response.Although research has investigated the pathological mechanisms underlying DN,effective treatment options remain limited.AIM To evaluate the therapeutic impact of Shenzhuo formulation(SZF)on a DN mouse model and to examine its potential molecular mechanisms using transcriptomic and metabolomic approaches.METHODS We established a DN mouse model through a high-fat diet combined with streptozotocin(STZ)injection,followed by SZF treatment.We analyzed SZF’s effects on gene expression and metabolite profiles in renal tissues of DN mice using transcriptomics and metabolomics techniques.Additionally,based on transcriptomic and non-targeted metabolomic findings,we further assessed SZF’s influence on the expression of factors related to the cytochrome P450(CYP450)-mediated arachidonic acid(AA)metabolism pathway,as well as its effects on inflammation and oxidative stress.RESULTS SZF intervention significantly decreased hyperglycemia and mitigated renal function impairment in DN mice.Pathological analysis revealed that SZF treatment improved renal tissue damage,reduced fibrosis,and diminished glycogen deposition.Transcriptomic analysis indicated that SZF influenced mRNA expression of CYP450-related genes,including Cyp2j13,Cyp2b9,Pla2 g2e/Cyp4a12a,Cyp4a32,Cyp2e1,and Cyp4a14.Non-targeted metabolomic results demonstrated that SZF altered the levels of metabolites associated with the AA metabolic pathway,including 5,6-EET,14,15-EET,phosphatidylcholine,and 20-HETE.Further experiments showed that SZF upregulated the expression of CYP4A and CYP2E proteins in renal tissue,as well as CYP2J and CYP2B proteins.Additionally,SZF significantly reduced the expression of inflammatory factors in renal tissue,enhanced antioxidant enzyme activity,and alleviated oxidative stress.CONCLUSION SZF exerts anti-inflammatory and antioxidant effects by regulating CYP450-mediated AA metabolism,leading to improved renal function and improved pathological state in DN mice. 展开更多
关键词 Diabetic nephropathy Shenzhuo formulation TRANSCRIPTOMIC METABOLOMIC Cytochrome P450 Arachidonic acid metabolic INFLAMMATORY Oxidative stress
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A two-field mixed formulation with scattered pressure node distribution in element-free Galerkin method for alleviating volumetric locking in hyperelastic materials
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作者 S.Sai Kumar Albert Shaji Nelson Muthu 《Acta Mechanica Sinica》 2025年第10期115-131,共17页
Rubber-like materials that are commonly used in structural applications are modelled using hyperelastic material models.Most of the hyperelastic materials are nearly incompressible,which poses challenges,i.e.,volumetr... Rubber-like materials that are commonly used in structural applications are modelled using hyperelastic material models.Most of the hyperelastic materials are nearly incompressible,which poses challenges,i.e.,volumetric locking during numerical modelling.There exist many formulations in the context of the finite element method,among which the mixed displacementpressure formulation is robust.However,such a displacement-pressure formulation is less explored in meshfree methods,which mitigates the problem associated with mesh distortion during large deformation.This work addresses this issue of alleviating volumetric locking in the element-free Galerkin method(EFGM),which is one of the popular meshfree methods.A two-field mixed variational formulation using the perturbed Lagrangian approach within the EFGM framework is proposed for modelling nearly incompressible hyperelastic material models,such as Neo-Hookean and Mooney-Rivlin.Taking advantage of the meshless nature of the EFGM,this work introduces a unique approach by randomly distributing pressure nodes across the geometry,following specific guidelines.A wide spectrum of problems involving bending,tension,compression,and contact is solved using two approaches of the proposed displacement-pressure node formulation involving regular and irregular pressure node distribution.It is observed that both approaches give accurate results compared to the reference results,though the latter offers flexibility in the pressure nodal distribution. 展开更多
关键词 Volumetric locking Mixed displacement-pressure formulation EFG method Irregular pressure node distribution Hyperelastic materials
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The 2025 China New-Formulation Detergent Products Development Conference & The 2025 China Daily Chemicals Forum on Biodegradable,Recyclable and Renewable Technologies Successfully Concluded
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作者 The editorial office 《China Detergent & Cosmetics》 2025年第4期89-90,共2页
The“2025 China New-Formulation Detergent Products Development Conference & 2025 China Daily Chemicals Biodegradable,Recyclable,Renewable Technology Innovation Summit”,cohosted by the China Research Institute of ... The“2025 China New-Formulation Detergent Products Development Conference & 2025 China Daily Chemicals Biodegradable,Recyclable,Renewable Technology Innovation Summit”,cohosted by the China Research Institute of Daily Chemical(RIDCI),was held in Yangzhou,Jiangsu Province.The event brought together over 230 representatives from government agencies,industry associations,and leading enterprises to contribute insights for the high-quality development of China's daily chemical industry. 展开更多
关键词 biodegradable technologies daily chemicals industry recyclable technologies CONFERENCE renewable technologies summit new formulation detergent products high quality development
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High-efficiency γ-aminobutyric acid nano-formulation for turnip mosaic virus:excellent adhesion performance and amplified plant defensive responses
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作者 Chao Zhang Jingyi Chen +5 位作者 Yubo Wen Yichao Liu Xuan Li Shuo Yan Jianjun Zhao Jun Li 《Horticultural Plant Journal》 2025年第6期2285-2288,共4页
Chinese cabbage(Brassica rapa subsp.pekinensis)is a widely cultivated vegetable crop in Asia with significant economic importance(Li et al.,2024;Yu et al.,2024).As a potyvirus with the broad host range,turnip mosaic v... Chinese cabbage(Brassica rapa subsp.pekinensis)is a widely cultivated vegetable crop in Asia with significant economic importance(Li et al.,2024;Yu et al.,2024).As a potyvirus with the broad host range,turnip mosaic virus(TuMV)is a major pathogen affecting Chinese cabbages,leading to severe yield losses(Li et al.,2019).Traditional control measures have shown limited efficacy,and the long-term use of chemical pesticides has led to significant issues such as environmental pollution and pathogen resistance(Samara et al.,2021;Lu et al.,2022).Biologicallyderived pesticides have garnered considerable attention owing to their eco-friendly attributes(Ayilara et al.,2023).γ-Aminobutyric acid(GABA),initially discovered in potato tubers,has been proven to regulate immune responses and enhance resistance to fungal and bacterial pathogens by modulating reactive oxygen species and stress-related hormone signals(Tarkowski et al.,2020;Wang et al.,2025).But biologically-derived agents typically face challenges such as large particle size and instability,which limit their practical application and bioavailability(Daraban et al.,2023). 展开更多
关键词 turnip mosaic virus chemical pesticides mosaic virus tumv control measures aminobutyric acid environmental pollution high efficiency nano formulation
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Standardization of nasal airway structure model of Chinese Han nationality for characterization of nasal formulation spatial deposition atlases
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作者 Zeru Li Huipeng Xu +8 位作者 Siwen Wang Qin Nie Bingqian Jia Jiawen Su Guanghong Xu Rui Yang Zhigang Wang Jiwen Zhang Li Wu 《Acta Pharmaceutica Sinica B》 2025年第12期6698-6713,共16页
The deposition characteristics of nasal formulations directly determine the efficacy of the drugs,whilst the complexity of human nasal airway structure encumbers quantitative evaluation of nasal spatial deposition.Mal... The deposition characteristics of nasal formulations directly determine the efficacy of the drugs,whilst the complexity of human nasal airway structure encumbers quantitative evaluation of nasal spatial deposition.Male and female standard nasal airway structure models were calculated from computed tomography data of 128 Chinese Han nationality using statistical shape model.The deposition evaluation devices were further designed,and an imaging method was then employed to obtain drug deposition information.Furthermore,drug spatial deposition atlases were proposed by UV unwrapping,a mathematical mapping procedure flattening three-dimensional(3D)information to two-dimension bidirectionally,to achieve quantification of drug deposition fractions in the regions of interest.Moreover,the feasibility and universality of this method were verified by correlating it with the chemical quantitative results and computational fluid dynamic simulation of drug deposition of mometasone furoate nasal spray and hydroxypropyl methylcellulose nasal powder,respectively.Finally,the unique drug spatial deposition atlases of these two formulations in the male and female evaluation devices were generated,respectively.In summary,the standard nasal airway structure models of the Chinese Han nationality and the drug spatial deposition atlases provide scientific tools for the formulation optimization and quality control of nasal formulations. 展开更多
关键词 Chinese Han nationality Statistical shape model Standard nasal airway structure model Spatial deposition atlas Deposition fraction Nasal formulation Nasal spray Nasal powder
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用于爆炸流场与结构间相互作用分析的Euler-Lagrange耦合模拟技术 被引量:7
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作者 浦锡锋 王仲琦 +1 位作者 白春华 周刚 《爆炸与冲击》 EI CAS CSCD 北大核心 2011年第1期6-10,共5页
介绍了1种把Eulerian计算过程和Lagrangian计算过程耦合起来的数值技术,编写了计算程序,把爆炸流场作用过程和结构动力学响应过程的计算结合起来,实现了爆炸流场对结构加载和结构动力响应及对爆炸流场反作用过程的模拟。利用Eulerian过... 介绍了1种把Eulerian计算过程和Lagrangian计算过程耦合起来的数值技术,编写了计算程序,把爆炸流场作用过程和结构动力学响应过程的计算结合起来,实现了爆炸流场对结构加载和结构动力响应及对爆炸流场反作用过程的模拟。利用Eulerian过程的流体弹塑性有限差分计算程序MMIC(multi-materials in cell)模拟爆炸流场发展过程,利用Lagrangian过程的结构动力学有限元计算程序模拟结构响应。应用Euler-Lagrange耦合技术分析了爆炸作用下飞片的变形、破坏和对靶体的侵彻过程,计算结果表明,本文的方法可以较好地反映流场与结构各自的运动发展及相互间作用过程。 展开更多
关键词 爆炸力学 侵彻 euler-lagrange耦合技术 飞片
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入水问题的Euler-Lagrange流固耦合数值模拟技术研究 被引量:3
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作者 浦锡锋 王仲琦 +1 位作者 白春华 周刚 《计算力学学报》 CAS CSCD 北大核心 2013年第S1期159-163,共5页
针对结构入水过程的特点,建立了一种把Eulerian计算过程和Lagrangian计算过程耦合起来的数值技术,编写了计算程序,把结构对水作用的过程和结构动力学响应过程的计算结合起来,实现了结构与水之间流固耦合作用过程的模拟.其中水、空气的... 针对结构入水过程的特点,建立了一种把Eulerian计算过程和Lagrangian计算过程耦合起来的数值技术,编写了计算程序,把结构对水作用的过程和结构动力学响应过程的计算结合起来,实现了结构与水之间流固耦合作用过程的模拟.其中水、空气的运动利用Eulerian过程的流体弹塑性有限差分计算程序进行模拟,结构的运动变形利用Lagrangian过程的结构动力学有限元计算程序模拟结构响应.通过板入水问题的计算结果与商业软件计算结果进行比较,验证了计算方法对流固间相互作用处理的正确性.本文计算程序可用于一般入水问题的结构响应-流场运动分析中. 展开更多
关键词 入水 数值模拟 euler-lagrange耦合技术
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有向图中网络Euler-Lagrange系统的自适应协调跟踪 被引量:18
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作者 梅杰 张海博 马广富 《自动化学报》 EI CSCD 北大核心 2011年第5期596-603,共8页
基于一致性理论,在有向图中研究网络Euler-Lagrange系统的协调跟踪控制.所有跟随智能体的动力学模型均为Euler-Lagrange方程.在仅有部分跟随智能体能获取领航智能体信息的情形下,同时考虑系统模型的参数不确定性,设计分布式自适应控制... 基于一致性理论,在有向图中研究网络Euler-Lagrange系统的协调跟踪控制.所有跟随智能体的动力学模型均为Euler-Lagrange方程.在仅有部分跟随智能体能获取领航智能体信息的情形下,同时考虑系统模型的参数不确定性,设计分布式自适应控制律实现所有跟随智能体对领航智能体的跟踪.针对领航智能体的运动状态,考虑以下两种情形:1)领航智能体为固定点;2)领航智能体为动态点.对第一种情形,设计的控制律使得所有跟随智能体渐近交会于固定点;对第二种情形,首先对每个跟随智能体设计分布式连续估计器,然后提出了分布式自适应控制律.当每个跟随智能体均能获取领航智能体的加速度信息时,设计的控制律能实现对领航智能体的渐近跟踪,当跟随智能体不能获取领航智能体的加速度信息时,跟踪误差是有界的.最后通过仿真分析验证设计的控制算法是合理有效的. 展开更多
关键词 多智能体系统 协调跟踪 分布式控制 自适应控制 euler-lagrange系统
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Bioavailability of 10-hydroxycamptothecin-phospholipid complex loaded by solid dispersion and lipid-based formulations 被引量:3
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作者 吴先闯 郝海军 +3 位作者 刘瑜新 宋晓勇 张永州 张红芹 《Journal of Chinese Pharmaceutical Sciences》 CAS CSCD 2015年第12期780-788,共9页
Previous study has shown that 10-hydroxycamptothecin(HCPT) has well-established pharmacological effects in vitro.However,its in vivo bioavailability is very poor due to various problems,which severely restricts its ... Previous study has shown that 10-hydroxycamptothecin(HCPT) has well-established pharmacological effects in vitro.However,its in vivo bioavailability is very poor due to various problems,which severely restricts its clinical applications.In the present study,phospholipid complex(PC) technology was employed to improve the solubility and bioavailability of HCPT.XRD data confirmed the formation of HCPT-PC.However,our previously prepared HCPT-PC is too sticky,which may result in the slow dissolution rate and negative effects on its absorption.Therefore,we prepared HCPT-PC-solid dispersion(HCPT-PC-SD)and lipid-based formulations of HCPT-PC through simple preparation process.The results showed that the dissolution rate of HCPT-PC was effectively improved by solid dispersion technology,which reached 91.73%in 45 min.Pharmacokinetic study revealed that the AUC_(0-t) of HCPT-PC-SD and HCPT-PC lipid-based formulations was effectively further increased compared with HCPT-PC.Moreover,we found that the combination of SD technology and lipid-base formulations could be a promising drug-delivery system to improve the oral bioavailability of HCPT-PC.In addition,we showed that the bioavailability of HCPT-PC lipid-base formulations was even greater than that of HCPT-PC-SD.In particular,lipid-base formulations could be prepared just by a simple method,suggesting its feasibility of industrialization. 展开更多
关键词 10-HYDROXYCAMPTOTHECIN Phospholipid complex Solid dispersion Lipid-based formulations BIOAVAILABILITY
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多体系统Euler-Lagrange方程的最小二乘法与违约修正 被引量:19
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作者 赵维加 潘振宽 《力学学报》 EI CSCD 北大核心 2002年第4期594-603,共10页
针对受完整约束的多体系统动力学Euler-Lagrange方程,在其传统的直接增广算法和零空间方法基础上提出了当系统存在冗余约束情形下的最小二乘法.同时,对应于最小二乘法提出了改进的约束违约修正方法.本文还针对Euler-Lagrange方程的计算... 针对受完整约束的多体系统动力学Euler-Lagrange方程,在其传统的直接增广算法和零空间方法基础上提出了当系统存在冗余约束情形下的最小二乘法.同时,对应于最小二乘法提出了改进的约束违约修正方法.本文还针对Euler-Lagrange方程的计算过程给出了相应Jacobi矩阵的QR分解和零空间连续正交基的算法.最后,以平行五连杆机构给出了数值结果并与部分现有方法进行比较. 展开更多
关键词 多体系统 euler-lagrange方程 违约修正 冗余约束 最小二乘法 平行五连杆机构
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引水隧洞施工通风Euler-Lagrange两相流大涡模拟 被引量:10
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作者 王晓玲 朱泽彪 +2 位作者 刘震 刘长欣 禹旺 《天津大学学报(自然科学与工程技术版)》 EI CSCD 北大核心 2017年第7期725-731,共7页
目前,地下通风两相流研究主要集中在矿井巷道通风且研究多采用雷诺时均法,无法准确获取湍流瞬态信息以及尘粒在湍流脉动影响下的瞬时运移规律.本文基于分子动理学理论,建立考虑热交换的三维非稳态EulerLagrange两相流颗粒轨道大涡模型,... 目前,地下通风两相流研究主要集中在矿井巷道通风且研究多采用雷诺时均法,无法准确获取湍流瞬态信息以及尘粒在湍流脉动影响下的瞬时运移规律.本文基于分子动理学理论,建立考虑热交换的三维非稳态EulerLagrange两相流颗粒轨道大涡模型,实现了对引水隧洞施工通风两相流的大涡数值模拟,揭示了引水隧洞风流场瞬态发展机制及颗粒在大涡结构影响下的运移规律,并验证了模型的准确性.运用该模型模拟某水电站引水隧洞施工通风排尘过程,结果表明:大涡模拟能捕捉到湍流脉动细节,结果较雷诺时均法更接近实际;通风可有效降低工作面附近温度;颗粒分布由初始的颗粒簇逐渐弥散,最终对隧洞全断面造成污染;通风3,700,s后,绝大多数颗粒从隧洞出口排出. 展开更多
关键词 引水隧洞 三维非稳态euler-lagrange两相流大涡模拟模型 湍流瞬态信息 粉尘颗粒运移 热交换
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