A novel borate compound YBa(3)B(9)O(18) has crystallized in a melt of BaYB(9)O(16). Single-crystal X-ray diffraction measurements reveal that YBa(3)B(9)O(18) adopts a hexagonal space group P6(3)/m with cell parameters of a = 7.1761(6) A and c = 16.9657(6) A. The structure is made up of the planar B(3)O(6) groups parallel to each other along the (001) direction, regular YO(6) octahedra, and irregular BaO(6) and BaO(9) polyhedra to form an analogue structure of beta-BaB(2)O(4). A series of isostructural borate compounds RBa(3)B(9)O(18) (R = Y, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb) were prepared by powder solid-state reactions. The DTA and TGA curves of YBaB(9)O(16) show an obvious weight loss at about 955 degrees C associated with a decomposition into YBO(3), B(2)O(3), and YBa(3)B(9)O(18) due to its incongruent melting behavior. The DTA and TGA curves of YBa(3)B(9)O(18) show that it is chemically stable and a congruent melting compound. A comparison of the structures of YBa(3)B(9)O(18) and beta-BaB(2)O(4) is presented.

In order to solve the high-efficiency removal of difficult-to-cut materials such as titanium alloys, this paper conducts a in-depth research on the process characteristics of short electric arc milling machining (SEAM). The effects of processing conditions on material removal rate (MRR), tool wear ratio (TWR) and surface roughness (Ra) are studied. DeWesoft high-speed acquisition system, scanning electron microscope (SEM) and energy spectrometer (EDS) are used to characterize the machining performance of Ti-6Al-4V in SEAM. The results show that the surface of the machined Ti-6Al-4V has an obvious central depressions, surrounded by edge bumps and wrinkles caused by the melt. The effective number of short electric arc discharge is high, and the discharge rate can be maintained at a high level, increasing utilization rate of electric energy. The peak current of normal discharge reaches more than 900 A, which can generate a higher MRR. In addition, the surface morphology, re-solidified layer, and particle morphology of Ti-6Al-4V used for SEAM are also studied. These results lay a theoretical and technical foundation for the industrial application of SEAM.

The incidence of synchronous lung tumors is rare, as reported in various clinical series, ranging from 0.2% to 8%. Most reported cases of synchronous tumors were shown to have the same histologic types of lung cancer. Among possible combinations, squamous cell carcinoma was by far the most common. Primary pulmonary lymphoma (PPL) is very rare in clinics accounting for only 0.5-1% of primary lung tumors. There is no report about synchronous primary pulmonary adenocarcinoma presenting with lung lymphoma. It can be easily misdiagnosed or missed. Although the treatment of PPL and synchronous pulmonary tumors has controversial, surgery with/without postoperative adjuvant radio-chemotherapy are used for most patients in present. We describe a case of synchronous primary lung tumors presenting with lymphoma and adenocarcinoma, in which expression of the cell surface antigens were evaluated immunohistochemically. By taking into consideration of the reported experiences, the author discusses the clinical features, prognostic criteria and therapeutic management of synchronous lung cancer and PPL.