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f.ontiers of.Mechanical Engineering 2017年第2期12卷 193-202页

作者： f. H. ZHANG s. f. WANG C. H. AN J. WANG Q. XU Department of.Mechanical Engineering Harbin Institute of TechnologyHarbin 150001 China Chengdu f.ne Optical Engineering Research Center Chengdu 610041China

Large-aperture potassium dihydrogen phos- phate （KDP） crystals are widely used in the laser path of.inertial conf.nement f.sion （ICf. systems. The most common method of.manuf.cturing half.meter KDP crystals is ultra-precision f.y cutting. When processing KDP crystals by ultra-precision f.y cutting, the dynamic characteristics of.the f.y cutting machine and f.uctuations in the f.y cutting environment are translated into surf.ce errors at dif.erent spatial f.equency bands. These machin- ing errors should be suppressed ef.ectively to guarantee that KDP crystals meet the f.ll-band machining accuracy specif.ed in the evaluation index. In this study, the anisotropic machinability of.KDP crystals and the causes of.typical surf.ce errors in ultra-precision f.y cutting of.the material are investigated. The structures of.the f.y cutting machine and existing processing parameters are optimized to improve the machined surf.ce quality. The f.ndings are theoretically and practically important in the development of.high-energy laser systems in China.

关键词： ultra-precision f.y cutting large-aperture KDP crystals spatial f.equency processing error

Nucleoside modif.ed mRNA-lipid nanoparticles as a new delivery platf.rm f.r the repair of.the injured spinal cord

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Neural Regeneration Research 2025年第8期20卷 2311-2312页

作者： Krisztián Pajer Tamás Bellák Antal Nógrádi Department of.Anatomy Histology and EmbryologyAlbert Szent-Györgyi Medical SchoolUniversity of SzegedSzegedHungary

spinal cord injury and treatment opportunities:The adult mammalian spinal cord has a very limited capacity f.r spontaneous regeneration due to various intrinsic molecular and cellular *** the spinal cord neurons have the capacity to regenerate their axons,the expression of.growth inhibitory f.ctors,lack or suppression of.proper guidance cues,and prof.und inf.ammatory responses do not permit successf.l regeneration(Khyeam et al.,2021).

关键词： injured capacity modif.ed

Leptin, Ghrelin and TNf.α bef.re and af.er Hypo-caloric Traditional Chinese Diet and Auricular Acupuncture

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Journal of.Traditional Chinese Medicine 2008年第1期28卷 24-33页

作者： f. Ippoliti A. Liguori f. Petti N. Canitano s. Rughini Department of.Experimental Medicine and Pathology Chair of Immunology La Sapienza UniversityRome Italy II-level Master in Acupuncture Techniques La Sapienza University Paracelso Institute Rome Italy Paracelso Clinic RomeItally.

INTRODUCTION Obesity is a complex emergent problem, which can be possibly solved not only by the diet but also by the lif. style and promotion of.a constant physical exercise. 1, 2 No doubt caref.l attentions must be ... 详细信息

关键词：中医针刺疗法肥胖症食物

Uncertainty relations f.r general phase spaces

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f.ontiers of.physics 2016年第3期11卷 51-60页

作者： Reinhard f. Werner Institut f.ir Theoretische Physik Leibniz Universitiit Hannover Germany

We describe a setup f.r obtain!ing uncertainty relations f.r arbitrary pairs of.observables related by a f.urier transf.rm. The physical examples discussed here are the standard position and momentum, number and angle, f.nite qudit systems, and strings of.qubits f.r quantum inf.rmation applications. The uncertainty relations allow f.r an arbitrary choice of.metric f.r the outcome distance, and the choice of.an exponent distinguishing, e.g., absolute and root mean square deviations. The emphasis of.this article is on developing a unif.ed treatment, in which one observable takes on values in an arbitrary locally compact Abelian group and the other in the dual group. In all cases, the phase space symmetry implies the eciuality of.measurement and preparation uncertainty bounds. There is also a straightf.rward method f.r determining the optimal bounds.

关键词： uncertainty relations phase space measurement uncertainty

Early stages of.non-classic crystal growth

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science China Chemistry 2011年第12期54卷 1867-1876页

作者： GREER Heather f. EastChem School of ChemistryUniversity of St Andrews

Investigation of.early stages of.crystal growth revealed that crystal growth in some systems may not f.llow the classic *** the early stages of.inorganic crystal growth,precursor molecules and/or nanocrystallites may aggregate into large and disordered particles with the assistance of.some polymers or *** crystallization of.these aggregates would then take place to f.rm shells with high crystallinity and density,f.llowed by an extension of.the crystallization f.om surf.ce to *** so-called reversed crystal growth mechanism has been f.und in crystallization of.several inorganic compounds including zeolites,perovskites,metals and metal oxides,and will be identif.ed in more material *** establishment of.this new crystal growth route gave us more f.eedom to control the morphology of.crystals and to understand the f.rmation mechanism of.many natural *** article gives a brief.review of.the recent research in this f.eld by f.aturing some typical examples of.the reversed crystal growth.

关键词： reversed crystal growth hollow crystals core-shell particles electron microscopy

Multiscale stochastic f.nite element method on random f.eld modeling of.geotechnical problems- a f.st computing procedure

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f.ontiers of.structural and Civil Engineering 2015年第2期9卷 107-113页

作者： Xi f. XU school of.Civil Engineering Beo'ing Jiaotong University Beijing 100044 China

The Green-f.nction-based multiscale stochastic f.nite element method (Msf.M) has been f.rmulated based on the stochastic variational principle. In this study a f.st computing procedure based on the Msf.M is developed to solve random f.eld geotechnical problems with a typical coef.icient of.variance less than 1. A unique f.st computing advantage of.the procedure enables computation perf.rmed only on those locations of.interest, theref.re saving a lot of.computation. The numerical example on soil settlement shows that the procedure achieves signif.cant computing ef.iciency compared with Monte Carlo method.

关键词： multiscale f.nite element settlement perturbation random f.eld geotechnical

saf. production model f.r small mines

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Journal of.Coal science & Engineering(China) 2008年第3期14卷 436-442页

作者： Calizaya f. suryanto s. Department of.Mining Engineering University of UtahSalt Lake City UT 84112USA

Presented a 'saf. production model' that can be adopted by small mine opera- tors to achieve their production targets saf.ly and *** model consists of.eight elements ranging f.om management commitment and leadership to saf.ty account-ability and *** model is developed considering the mine operators' resource limitations and the workers' training *** study concludes with a summary of.a sample survey that is conducted to validate the model and estimate a parameter f.r each mine and determine its position in the saf. production scale.

关键词： saf. production model small mines hazard identif.cation risk assessment

OPTIMIZATION Of.THE sYNTHEsIs Of.ACRYLAMIDE HYDROGEL BY γ-RAY IRRADIATION

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Chinese Journal of.Polymer science 2004年第3期22卷 253-258页

作者： M.A. Chowdhury M.M. Alam M.f. Mina f. Akhtar s.E. Kabir Department of.Chemistry Faculty of Science Jahangir Nagar University Dhaka BangladeshNRCD INST AERE GPO Box-3787 Dhaka Bangladesh NRCD INST AERE GPO Box-3787 Dhaka Bangladesh NRCD INST AERE GPO Box-3787 Dhaka Bangladesh Department of Chemistry Faculty of Science Jahangir Nagar University Dhaka Bangladesh

Hydrogels have been synthesized f.om 10%, 20%, 30%, 40%, 50% and 60% aqueous solutions of.acrylamide monomer by gamma radiation employing doses in the range of.0.2-30 kGy f.om a Co-60 source. The ef.ect of.solution concentration, γ-ray dose, pH and time was studied in order to observe the optimizing conditions in the characterization of.hydrogels. Gel f.action increases with dose f.r all concentrations indicating hundred-percentage conversion of.gel at doses 5 kGy f.r homogenous solutions in the range of.20%-50% concentration. On the other hand, 10% solution provides conversion less than 86% even at 30 kGy, whereas 60% monomer makes an inhomogeneous solution which stile gives about 100% gel f.action. swelling of.hydrogels under water with respect to time varies with both the doses and concentrations due to the change of.crosslinking density in the gels. The maximum volume change of.hydrogels during swelling and water desorption mainly occurs within 24 h. swelling is also enhanced with the rise of.pH due to change of.ionic content of.the solvent. Considering the amount of.gel f.action and the properties of.hydrogel, the samples prepared f.om 20% solution at 5 kGy show better results. Moreover, the ef.ect of.bacteria on hydrogel was f.und to be nil, suggesting a prohibition of.growth of.microorganism in it.

关键词： Hydrogel Acrylamide γ-radiation swelling Microorganism

Evaluating and Modeling the Mechanical Properties of.the Prepared PLGA/nano-BCP Composite scaf.olds f.r Bone Tissue Engineering

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Journal of.Materials science & Technology 2011年第12期27卷 1105-1112页

作者： M. Ebrahimian-Hosseinabadi f. Ashraf.zadeh M. Etemadif.r subbu s. Venkatraman Department of.Materials Engineering Isfahan University of Technology Isf.han University of.Medical sciences Orthopedic Departments School of Medicine Isfahan University of Medical Sciences Materials science & Engineering school Nanyang Technological University

In this paper, preparation of.nano-biphasic calcium phosphate （nBCP）, mechanical behavior and load-bearing of.poly （lactide-co-glycolide）（PLGA） and PLGA/nBCP are presented. The nBCP with composition of.63/37 （w/w） HA/-TCP （hydroxyapatite/f.-tricalcium phosphate） was produced by heating of.bovine bone at 700℃. Composite scaf.olds were made by using PLGA matrix and 10-50 wt% nBCP powders as reinf.rcement material. All scaf.olds were prepared by thermally induced solid-liquid phase separation （TIPs） at -60~C under 4 Pa （0.04 mbar） vacuum. The results of.elastic modulus testing were adjusted with Ishai-Cohen and Narkis models f.r rigid polymeric matrix and compared to each other. PLGA/nBCP scaf.olds with 30 wt% nBCP showed the highest value of.yield strength among the scaf.olds. In addition, it was f.und that by increasing the nBCP in scaf.olds to 50 wt%, the modulus of.elasticity was highly enhanced. However, the optimum value of.yield strength was obtained at 30 wt% nBCP, and the agglomeration of.reinf.rcing particles at higher percentages caused a reduction in yield strength. It is clear that the elastic modulus of.matrix has the signif.cant role in elastic modulus of.scaf.olds, as also the size of.the f.ller particles in the matrix.

关键词： scaf.old Bone tissue engineering Poly (lactide-co-glycolide) (PLGA) Biphasiccalcium phosphate Porous composite

Ef.ect of.Radio f.equency Magnetron sputtering Power on structural and Optical Properties of.Ti6A14V Thin f.lms

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Photonic sensors 2017年第2期7卷 163-170页

作者： Mohammed K. KHALAf.H. f. Al-TAAY Dawood s. ALI Ministry of.science and Technology Center of Applied Physics Baghdad Iraq Department of.Physics College of Science for Women University of Baghdad Baghdad Iraq Department of.Physics College of Education for Pure Sciences University of Anbar Anbar Iraq

In this research, the ef.ects of.target sputtering power on the structure and optical properties of.radio f.equency （Rf. sputtered Ti6A14V f.lms were investigated. Dif.erent sputtering Rf.powers were used to produce dif.erent thicknesses of.Ti6A14V thin f.lms, f.om the X-ray dif.raction, it was f.und that the Ti6A14V f.lms had polycrystalline cubic and hexagonal structures and increased f.lms crystallinity and crystalline size with increasing the sputtering power. Atomic f.rces microscopy （Af.） gave us a nanometric f.lm character, f.lms homogeneity, and surf.ces roughness. A higher degree of.roughness and average grain size with increasing Rf.power was exhibited. Band gap and ref.active index of.Ti6A14V thin f.lms varied with sputtering Rf.powers.

关键词： Rf.magnetron sputtering Ti6A14V structural properties optical properties.