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11.
The information on the force of extraocular muscles(EOMs)is beneficial for strabismus diagnosis and surgical planning,and a direct and simple method is important for surgeons to obtain these forces.Based on the traditional model,a numerical simulation method was proposed to achieve this aim,and then the active force of the lateral rectus(LR)muscle was successfully simulated when the eye rotated every angle from 0°to 30°in the horizontal plane from the nasal to the temporal side.In order to verify these simulations,the results were compared with the previous experimental data.The comparison shows that the simulation results diverged much more than the experimental data in the range of 0°–10°.The errors were corrected to make the simulation results closer to the experimental data.Finally,a general empirical equation was proposed to evaluate the active force of the LR muscle by fitting these data,which represent the relationship between the simulation forces and the contractive amounts of the LR muscle.  相似文献   
12.
The hard X-ray modulation telescope HXMT is a low orbit X-ray space telescope whose main science goals are to accomplish a hard X-ray all sky survey and to study timing and spectral characteristics of X-ray sources. HXMT has three kinds of science instruments: the high energy X-ray detector (HE), the medium energy X-ray detector (ME) and the low energy X-ray detector (LE). The observation schedule of HXMT is a key to achieving the science goal of HXMT, and the analysis of the observation constraints is one of the first tasks in making the observation schedule. This paper analyzes how the observation constraints influence the sky visibility and the visible time distribution of X-ray sources and discusses the schedule strategy with regard to the observation constraints.  相似文献   
13.
“Dogel ebs” was known as Sophora flavescens Ait., a classical traditional Chinese Mongolian herbal medicine, which had the effects on damp‐heat dysentery, scrofula, and syndrome of accumulated dampness toxicity. Although the chemical constituents have been clarified by our previous studies, the metabolic transformation of “Dogel ebs” in vivo was still unclear. To explore the mechanism of “Dogel ebs,” the metabolites in plasma, bile, and urine samples were investigated. A fast positive and negative ion switching technology was used for the simultaneous determination of flavonoids and alkaloids in “Dogel ebs” in a single run. And a target‐group‐change coupled with mass defect filtering strategy was utilized to analyze the collected data. 89 parent compounds and 82 metabolites were characterized by high‐performance liquid chromatography with quadrupole exactive Orbitrap mass spectrometry. Both phase I and phase II metabolites were observed and the metabolic pathways involved in oxidation, demethylation, acetylation, and glucuronidation. 69 metabolites of “Dogel ebs,” including three hydroxyls bonding xanthohumol, formononetin‐7‐O‐glucuronide, 2′‐hydroxyl‐isoxanthohumol decarboxylation metabolite, oxysophocarpine dehydrogen, 9α‐hydroxysophoramine‐O‐glucuronide, etc. were reported for the first time.  相似文献   
14.
本文综述了近年来车用燃料电池电催化的发展状况,分析了车用燃料电池电催化的发展趋势,重点介绍了大连化学物理研究所在燃料电池电催化方面的研究进展.指出车用燃料电池电催化的发展方向是提高现有铂基催化剂的活性,在保证车用燃料电池在变载等动态工况下的可靠性与寿命的前提下,应降低膜电极的贵金属铂用量,发展低铂/非铂电催化剂.针对车用燃料电池的使用条件,应发展抗燃料气与空气中杂质的电催化方法与抗腐蚀催化剂载体.从长远考虑,重点发展碱性聚合物膜燃料电池,拓展利于活化顺磁性氧的催化方法,有望摆脱车用燃料电池对铂催化剂的依赖.  相似文献   
15.
Ce/Sm ions are covalently grafted to a Keggin polyoxomolybdate cluster[PMo12O40]3-to yield interesting fluorescent-photodarkening molecular systems.Their photoresponce processes are observed to be activated via energy transfer from luminescent fragments to photocoloration components.  相似文献   
16.
18O重离子束轰击厚天然铅靶,通过多核子转移反应生成208Hg核.辐照铅片放入离线熔化铅靶气相热色谱装置中处理,分离并收集汞元素产物.完成了4πΔEβγ-γ,γX(γ)关联事件谱及γ射线时序单谱测量.建议了21条γ射线,以及能量为1365,1727keV的两条208Tl新能级的208Hg β 衰变部分γ纲图.  相似文献   
17.
The 193 nm photodissociation dynamics of CH2 CHCOCl in the gas phase has been examined with the technique of time-resolved Fourier transform infrared emission (TR-FTIR) spectroscopy.Vibrationally excited photofragments of CO (≤ 5),HCl (≤ 6),and C2H2 were observed and two photodissociation channels,the C-Cl fission channel and the HCl elimination channel have been identified.The vibrational and rotational state distributions of the photofragments CO and HCl have been acquired by analyzing their fully rotationally resolved v→v-1 rovibrational progressions in the emission spectra,from which it has been firmly established that the mechanism involves production of HCl via the four-center molecular elimination of CH2 CHCOCl after its internal conversion from the S1 state to the S0 state.In addition to the dominant C-Cl bond fission along the excited S1 state,the S1→S0 internal conversion has also been found to play an important role in the gas phase photolysis of CH2 CHCOCl as manifested by the considerable yield of HCl.  相似文献   
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