[en] The effects of the parameters of RF system to electron beam intensity in Hefei storage ring are discussed in this paper. There appeared significant deviation respect to beam ideal orbit in the closed orbit distortion correction experiment, and therefore, necessary adjustments have been carried out for RF system parameters, such as frequency, cavity temperature, etc., to meet the requirement of intense beam injection. And the work have guidance effect to reconstruction of RF system in Phase II project of Hefei storage ring

[en] The constant temperature cooling water control system of HLS-II is used to control the cooling water temperature change, and reduces the effect of the external environment on the equipment to improve the stability of the light source operation. The system is a distributed control system based on EPICS, and uses a serial port Ethernet converter MOXA6450 to connect digital indicating controller UT55A-20 to the LAN. The temperature control is implemented in UT55A-20, and IOC runs on VMW are virtual machine. The system has been stable and reliable since 2015, and the control precision of cooling water temperature reaches ± 0.5℃ design indicators. The system provides the necessary technical support for the stable supply light of HLS-II. (authors)

[en] The cooling water temperature measures system for HLS (Hefei Light Source) adopts EPICS to the developing platform and takes the intelligence temperature cruise instrument for the front control instrument. Data of temperatures are required by IOCs through Serial Port Communication, archived and searched by Channel Archiver. The system can monitor the real-time temperatures of many channels cooling water and has the function of history data storage, and data network search. (authors)

[en] Background: The Hefei Light Source (HLS) is a VUV and soft X-ray synchrotron radiation source. An upgrade project was started at the end of 2009 to improve the performance of the light source. The cooling water monitor system is a part of this upgrade project. Purpose: This system is developed under EPICS environment to monitor 596 distributed signals of the cooling water system, including the water temperature, pressure and flow, magnet temperature, and environment temperature in the tunnel. Methods: The cRIO-9073 controller from National Instruments (NI) is used as the hardware platform. The software development is implemented using LabVIEW with the EPICS interface 'EPICS Server IO Server' from NI. A file with the hardware information, such as chassis serial number: model serial number, etc., is used by the software to configure the installed hardware. A self-check program is developed to check whether the software matches with the hardware via the configuration file. System mirror-image method is used for the software installation to effectively speed up the installation process. Results: The test results in the commissioning indicate that this system is reliable, flexible, and easy to operate. Conclusion: NI cRIO with LabVIEW can be used to effectively monitor a large number of distributed signals, and can be easily integrated into EPICS based control systems. (authors)

[en] The temperature is an important factor affecting the stability of electron beam orbits. For almost all accelerators, a well-working cooling system and the monitoring system are needed to keep the temperature constant. In this paper, the temperature monitor system for HLS based on EPICS, including its hardware, software and history database, is briefly introduced. It has been indicated that the system satisfies the requirement of machine study and operation. (authors)

[en] Electron beam welding experiments of TA15 titanium alloy to GH600 nickel superalloy with and without a copper sheet interlayer were carried out. Surface appearance, microstructure and phase constitution of the joint were examined by optical microscopy, scanning electron microscopy and x-ray diffraction analysis. Mechanical properties of Ti/Ni and Ti/Cu/Ni joint were evaluated based on tensile strength and microhardness tests. The results showed that cracking occurred in Ti/Ni electron beam weldment for the formation of brittle Ni-Ti intermetallics, while a crack-free electron beam-welded Ti/Ni joint can be obtained by using a copper sheet as filler metal. The addition of copper into the weld affected the welding metallurgical process of the electron beam-welded Ti/Ni joint significantly and was helpful for restraining the formation of Ti-Ni intermetallics in Ti/Ni joint. The microstructure of the weld was mainly characterized by a copper-based solid solution and Ti-Cu interfacial intermetallic compounds. Ti-Ni intermetallic compounds were almost entirely suppressed. The hardness of the weld zone was significantly lower than that of Ti/Ni joint, and the tensile strength of the joint can be up to 282 MPa.

[en] Highlights: • Joining of metal matrix composites is realized. • Eutectic reaction during cooling resulted in a novel multicellular microstructure. • Whisker reinforcement refine the matrix grains. • The joint fails in the transition region between BM and HAZ. The microstructure and mechanical properties of the 3.5 vol% TiBw/Ti6Al4V composite electron beam welded joint was investigated in this paper. The microstructure evolution during the cooling stage was anatomized. Microhardness and tensile strength were used to evaluate the mechanical performance. Results showed that a novel micro-network reinforcement distribution was constructed in the weld zone with a basket-weave microstructure of the matrix. The weld zone was composed of α-Ti, β-Ti, and TiB whiskers. Solid-state phase transformations, α phase to β phase and β phase to α’ phase were observed in the heat-affected zone. The microhardness value of the weld zone was almost uniformly distributed with an average value of 438 HV, which was higher than that of the heat-affected zone and base metal. The ultimate tensile strength of the joint could reach 96% (room temperature) and 94% (600 °C) of the base metal, respectively.

[en] The composite structures of TZM alloy and 30CrMnSiA steel have broad application prospects in nuclear power and aerospace industries, while the problem of the joint embrittlement has not been solved. Therefore, pure vanadium, which has excellent metallurgical compatibility with base materials is selected as the filler metal to produce high strength joints. Microstructures, mechanical properties, and TZM/FZ interfacial characteristics of the joints without V foil and with V foil were analyzed. The results indicate that: (i) there is a Fe₂Mo intermetallic compound layer along with the TZM/FZ interface without V foil, which will deteriorate the mechanical properties of the joint. After adding pure V foil, there is no reactive layer appearing at the TZM/FZ interface; (ii) the joint without V foil fractured along the interface between TZM and Fe₂Mo, the strength of which is only 165.2 MPa, while the tensile strength of the joint with V foil reaches 312.7 MPa; (iii) through calculating the interfacial ideal adhesion energy, it can be found that the interfacial bonding strength of the Mo (111)/V(Fe)_ss (111) interface is higher than that of the Mo (111)/Fe₂Mo(100) interface.

[en] Emerging evidence has indicated that transforming growth factor-beta 1 (TGF-β1) induces the epithelial–mesenchymal transition (EMT) in cancer cells, thus promoting their motility and invasiveness. Quercetin, a member of the polyphenolic flavonoid family, has been reported to display anticancer activity against a broad range of cancer cell types. Indeed, numerous studies have shown the cancer preventive effects and molecular mechanisms of quercetin in vitro using diverse cell model systems. However, the potential effect of quercetin on EMT remains unclear. In this study, we identified a unique function of quercetin in inhibiting the EMT process induced by TGF-β1. In particular, quercetin rescued the morphological changes and EMT-like phenotypes in TGF-β1-activated SW480 cells, and this inhibition of TGF-β1-induced EMT was mediated via the suppression of Twist1 expression. In addition, quercetin strongly suppressed TGF-β1-induced invasion of SW480 cells. Thus, quercetin may be considered a novel therapeutic agent for the treatment of patients with refractory cancer and for the prevention of the metastatic cascade initiated by EMT.

[en] To investigate the influence of microstructure evolution on mechanical properties of a molybdenum-titanium-zirconium (TZM) alloy joint welded by electron beam welding (EBW), detailed microstructure of the joint was examined by electron backscatter diffraction (EBSD) and transmission electron microscopy (TEM). The microhardness of the cross section was measured and tensile strengths at temperatures of 293 K as well as 1273 K were tested. The crystallized grains of weld zone (WZ) were coarsened severely, but the dispersed distribution of Mo₂C and ZrO₂ particles inside grains caused the microhardness of WZ to be higher than that of heat affected zone (HAZ). MoO₂ and TiO₂ precipitates easily segregated on grain boundaries due to microsegregation. Since the large differences in the interatomic distance between Mo/MoO₂ and Mo/TiO₂, the precipitates segregated on grain boundaries and Mo matrix were deemed to be incoherent. Thus, tensile strength of the welded joint was just 50% of that of base metal and the elongation was nearly decreased to zero with a brittle fracture mode.