Deposition and characterization of niobium films for SRF cavity application

Niobium coated copper cavities are an interesting alternative to bulk niobium ones for Superconducting Radio Frequency (SRF) applications to particle accelerators. The magnetron sputtering is the technology developed at CERN for depositing niobium Alms and applied over the past twenty years. Unfortunately, the observed degradation of the quality factor with increasing cavity voltage, not completely understood, prevents the use of this technology in future large accelerators designed to work at gradients higher than 30 MWm, with quality factors of the order of 1010 (or higher). At the beginning of the new millennium some new deposition techniques have been proposed to overcome the difficulties encountered with the sputtering technique. This paper compares the properties of niobium films obtained with the magnetron sputtering and with a cathodic arc deposition in ultra-high vacuum (UHVCA). The UHVCA-produced Nb Alms have structural and transport properties closer to the bulk ones, providing a promising alternative for niobium coated, highvoltage and high-Q copper RF cavities, with respect to the standard magnetron sputtering technique. Preliminary results and possible approaches to whole cavity UHVCA coating will be presented and discussed

A Business Plan of Love Baby Early Education Company

早期教育关系着国家和家庭的未来，拥有着庞大的市场需求和广阔的发展前景。随着新一代教育观念的更新、经济实力的增强和对社会竞争激烈程度的进一步认识，让孩子接受规范的早期启蒙教育，开发孩子优秀的情商、智商和逆商，已经成为社会潮流。本论文运用创业管理相关理论，通过对早期教育市场现状的分析和研究，结合市场需求问卷调查，提出厦门艾贝早期教育中心创业设想。研究表明，艾贝早期教育中心应该定位于中高端市场，通过加强早期教育中心的师资力量建设，开发创新独特的核心竞争力课程，因人施教，建立服务质量控制方法，注重管理团队建设，诚信经营，树立良好的品牌形象，赢取市场份额。通过估算，艾贝早期教育中心需投资200万元，预计...Early education relates with the future of the family and country. Its market is a huge market and has a wide prospect. With the education conceptual renewal and the enhanced economic strength and the understanding to the intensified social competition of the new generation, developing a good EQ and IQ and AQ of children has become a trend. Early education is a good way to it. The thesis analyses ...学位：工商管理硕士院系专业：管理学院工商管理教育中心（MBA中心）_工商管理硕士(MBA)学号：1792008115103

Status of Nb-Pb Superconducting RF-Gun Cavities

We report on the progress and status of an electron RFgun made of two superconductors: niobium and lead [1]. The presented design combines the advantages of the RF performance of bulk niobium superconducting cavities and the reasonably high quantum efficiency of lead. The design of RF-gun and performance of 3 test cavities without and with the emitting lead spot are reported in this contribution. Measured quantum efficiency for lead at 2K is presented briefly. More details are reported in [9]