6.17-W continuous wave operation of a 2132-nm c-cut Tm,Ho:YAP pumped by a laser diode of 794.3 nm

Continuous wave (CW) operation of a c-cut Tm (5 at %), Ho (0.3 at %):YAP laser at 2132 nm wavelength were reported in this paper. In the temperature of 77 K, the Tm,Ho:YAP crystal was double end-pumped by a 21.4 W fiber-coupled laser diode (LD) at the center wavelength of 794.3 nm. Different resonator lengths and output couplers for the total pump power were tried. The resonator length was 205 mm, and the maximum CW output power of 6.17 W was acquired, corresponding to an optical-optical conversion efficiency of 28.8% and a slope efficiency of 35.6%.     

电弧蒸馏光谱法测定地球化学样品中银及其他痕量元素的研究进展

发射光谱法因具有多元素同时测定,分析速度快,灵敏度高,检出限低,使用方便的特点,被用于地质样品中银及其他痕量元素的测定。随着我国地质勘查事业的发展和地球化学调查工作力度的加大,对覆盖区的多目标地球化学调查样品的测试及质量控制提出了更高的要求。同时分析方法和测试技术有了新的进展。基于蒸馏原理的电弧光谱测试技术也有了多方面的进展。本论文归纳总结了国内主要刊物上所发表的电弧蒸馏光谱法测定地球化学样品中银及其他痕量元素的研究和应用情况,重点就固体缓冲剂的组成成分进行简要概述,以期为今后样品测试提供参考。     

利多卡因醇质体的制备及其透皮性能评价

为了提高酰胺类局部麻醉药利多卡因的经皮渗透量,采取乙醇注入法制备了利多卡因醇质体,正交实验得到其最优制备工艺:卵磷脂与利多卡因质量比1∶1,乙醇体积分数40%,温度30℃,超声时间3min.该法制得利多卡因醇质体的平均包封率为(75.93±5.07)%.将该醇质体制成含裸药5%的凝胶,皮肤刺激性实验和体外透皮实验结果显示该凝胶对豚鼠皮肤无刺激性、无致敏性.该凝胶6h的体外累计渗透量为241.968μg.cm-2,6h的渗透速率(40.331μg.cm-2.h-1)为裸药凝胶渗透速率的7.71倍.     

NDT of the Shape of a Thin 3D Slit on the Metal Surface by Millimeter Waves

As the basis of the evaluation of nature cracks, a millimeter wave method to evaluate the shape of a thin 3D slit on the metal surface is demonstrated. An open-ended coaxial line sensor was proposed to improve the spatial resolution of the measurement. The amplitude of the reflection coefficient that is associated with the dimensions of the slit is measured by scanning the specimen in the direction perpendicular to the detected slit. A characteristic signal corresponding to the detected slit was obtained and, was used to evaluate the depth of the slit.     

Shape coexistence at high spin in187Au

High-spin states in¹⁸⁷Au have been populated in the¹⁷²Yb(¹⁹F, 4n) reaction and studied with in-beam spectroscopic techniques using the “Château de Cristal” 4π-multidetector array. A comprehensive level scheme of¹⁸⁷Au has been established. Experimental band crossing frequencies and gains in alignment were deduced. Shape coexistence in¹⁸⁷Au, well established at low spin, is found to survive up to spin 57/2, and manifests itself through well separated oblate and prolate structures.     

Measurability of vacuum fluctuations and dark energy

Vacuum fluctuations of the electromagnetic field induce current fluctuations in resistively shunted Josephson junctions that are measurable in terms of a physically relevant power spectrum. In this paper we investigate under which conditions vacuum fluctuations can be gravitationally active, thus contributing to the dark energy density of the universe. Our central hypothesis is that vacuum fluctuations are gravitationally active if and only if they are measurable   in terms of a physical power spectrum in a suitable macroscopic or mesoscopic detector. This hypothesis is consistent with the observed dark energy density in the universe and offers a resolution of the cosmological constant problem. Using this hypothesis we show that the observable vacuum energy density _ρvac${\rho }_{\mathit{vac}}$ in the universe is related to the largest possible critical temperature _Tc$T_c$ of superconductors through _ρvac=σ·(_kTc)⁴/?³c³${\rho }_{\mathit{vac}}=\sigma ·({\mathit{kT}}_c{)}^4/{?}^3{c}^3$, where σ$\sigma$ is a small constant of the order 10^-3${10}^{-3}$. This relation can be regarded as an analog of the Stefan–Boltzmann law for dark energy. Our hypothesis is testable in Josephson junctions where we predict there should be a cutoff in the measured spectrum at 1.7 THz if the hypothesis is true.     

空间光学遥感器大功率控制电箱的热设计

根据空间应用电子设备的热控要求,对空间光学遥感器的控制电箱进行了热控设计。首先,总结了空间电子设备的热设计原则。针对空间光学遥感器控制电箱介绍了相应的热设计流程,对典型的大功率器件进行了温差推算,并说明了电箱的各电路板和大功率元器件的热设计方案。最后,通过热分析和热试验手段对热控电箱的热控方案进行了验证。试验结果表明：控制电箱的整机稳态工况热平衡温度小于30℃,各元器件的最高壳温在54.2℃以内。结果验证了该设计方案完全满足设计指标要求。     

High-power,high-quality ZGP OPO pumped by a Tm,Ho:GdVO<Subscript>4</Subscript> laser

We report a ZGP OPO system capable of producing >6 W at a signal wavelength of 3.80 μm and an idler wavelength of 4.45 μm. The pumping source is the Tm,Ho:GdVO₄ laser operated at 2.049 μm with an M ² of 1.07. The ZGP OPO generated a total combined output power of 6.1 W at signal wavelength and idler wavelength under pumping power of 18.3 W, and an M ² of 1.7 for OPO output was obtained.     

向内发射磁绝缘振荡器

提出了一种向内发射磁绝缘振荡器,并给出了微波轴向提取的方法。这种新型结构通过外置阴极、内置阳极,使参与束波作用的轮辐电流通过阳极回流提供了自磁绝缘的角向磁场,有提高器件效率的可能。而外置阴极使阴极的发射面积增大,发射电流密度减小,有利于延长阴极寿命。通过粒子模拟,得到了几何参数与磁绝缘线振荡器输出功率的关系。在电压890 kV,电流56.1 kA下,输出功率为3.6 GW,频率为8.2GHz。